FXUS61 KBUF 300818 AFDBUF AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BUFFALO NY 418 AM EDT FRI AUG 30 2013 .SYNOPSIS... HIGH PRESSURE DRAPED ACROSS THE MID ATLANTIC STATES WILL DRIFT OFF THE EAST COAST TODAY. FOLLOWING THE DEPARTING HIGH...SEVERAL WAVES OF LOW PRESSURE WILL TRACK ACROSS THE GREAT LAKES AND BRING A RENEWED CHANCE FOR SHOWERS AND THUNDERSTORMS FROM LATE THIS AFTERNOON ON THROUGH THE HOLIDAY WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... THROUGH SUNRISE...EXPECT AREAS OF FOG AND LOW STRATUS TO REMAIN FAIRLY COMMONPLACE FROM THE WESTERN SOUTHERN TIER NORTHEASTWARD ACROSS PORTIONS OF THE FINGER LAKES TO THE NORTH COUNTRY...WHERE DEWPOINT DEPRESSIONS ARE GENERALLY THE LOWEST. AFTER THAT TIME... RENEWED DAYTIME HEATING SHOULD HELP MIX THIS OUT BY 9-10 AM OR SO. OTHERWISE...SURFACE HIGH PRESSURE DRAPED ACROSS THE MID ATLANTIC STATES WILL SLIDE OFF THE EAST COAST TODAY...ALLOWING A MODEST SHORTWAVE TROUGH AND ASSOCIATED WEAK SURFACE LOW CURRENTLY NEAR LAKE SUPERIOR TO DROP SOUTHEASTWARD INTO THE CENTRAL GREAT LAKES. IN ADVANCE OF THESE FEATURES...A FAIR AMOUNT OF MID AND HIGH LEVEL CLOUDINESS WILL OVERSPREAD OUR REGION FROM NORTHWEST TO SOUTHEAST TODAY...AND SHOULD EVENTUALLY RENDER SKIES MOSTLY CLOUDY THIS AFTERNOON ACROSS MOST AREAS NORTH OF THE SOUTHERN TIER. THIS SAID...PRECIP CHANCES LOOK TO REMAIN RELATIVELY MINIMAL AND BELOW THE CHANCE THRESHOLD...WITH THE EXCEPTION OF THE SAINT LAWRENCE VALLEY AND ADJOINING PORTIONS OF THE NORTH COUNTRY. IN THIS LATTER AREA...AN ENCROACHING FRONTAL BOUNDARY WILL BRING AT LEAST A SMALL RISK OF SOME SCATTERED CONVECTION DURING THE MID TO LATE AFTERNOON HOURS...FOR WHICH SOME LOW-MID CHANCE RANGE POPS WILL REMAIN IN PLAY. TEMPERATURE-WISE...850 MB TEMPS OF +15C TO +17C SHOULD GENERALLY TRANSLATE INTO FAIRLY WIDESPREAD HIGHS IN THE LOWER TO MID 80S...THOUGH THE INCOMING MID AND HIGH CLOUD COVER WILL LIKELY HOLD READINGS BACK A LITTLE FROM WHAT THEY OTHERWISE MIGHT BE. TONIGHT...THE AFOREMENTIONED SHORTWAVE AND ITS ELONGATING ATTENDANT SURFACE REFLECTION WILL EASE FURTHER SOUTHEASTWARD AND INTO THE LOWER GREAT LAKES...WITH THE SURFACE COLD FRONT REACHING NEARBY SOUTHERN ONTARIO BY LATE IN THE NIGHT. WITH PWATS INCREASING TO BETWEEN 1.50-1.75 INCHES AND LARGER-SCALE LIFT ON A GENERAL INCREASE GIVEN THE APPROACH OF THESE FEATURES AND A DEVELOPING WEAK LOW LEVEL JET...THIS SHOULD RESULT IN SLOWLY INCREASING CONVECTIVE POTENTIAL FROM NORTHWEST TO SOUTHEAST THROUGH THE NIGHT. THE GREATEST CHANCES FOR CONVECTION WILL AGAIN BE ACROSS THE SAINT LAWRENCE VALLEY AND NORTH COUNTRY...WHICH WILL SEE THE BEST COMBINATION OF LOW LEVEL CONVERGENCE AT THE NOSE OF THE AFOREMENTIONED LLJ AND LIFT FROM THE APPROACHING SHORTWAVE...AND WHERE SOME OF THE 00Z GUIDANCE PACKAGES /MOST NOTABLY THE 00Z GFS AND ECMWF/ CONSEQUENTLY SUGGEST THE POTENTIAL FOR AN MCS. GIVEN THE INHERENT DIFFICULTY THAT THE MODELS TYPICALLY HAVE IN HANDLING SUCH FEATURES...HAVE ELECTED TO KEEP POPS CAPPED IN THE CHANCE RANGE FOR NOW...THOUGH THESE MAY ULTIMATELY NEED TO BE RAISED TO LIKELY OR HIGHER ACROSS THE NORTH COUNTRY/SAINT LAWRENCE VALLEY SHOULD IT APPEAR THAT AN MCS WILL ACTUALLY COME TO FRUITION. OTHERWISE...EXPECT A WARMER AND MUGGIER NIGHT AS DEWPOINTS CREEP UPWARD AGAIN...AND ACT IN CONCERT WITH A MODEST SOUTH TO SOUTHWESTERLY LOW LEVEL FLOW TO KEEP NIGHTTIME LOWS FROM FALLING BELOW THE MID TO UPPER 60S IN MOST PLACES...WITH THE IMMEDIATE LAKESHORES OF FAR WESTERN NEW YORK LIKELY NOT DROPPING BELOW 70 DEGREES. && .SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/... ...LATE SUMMER WARMTH TO PERSIST INTO LABOR DAY... A STRONG RIDGE CENTERED OVER THE ROCKIES WILL GRADUALLY AMPLIFY DURING THIS PERIOD AS A VIGOROUS SHORTWAVE WILL TRACK EAST ALONG THE CANADIAN BORDER. THIS PATTERN CHANGING SHORTWAVE WILL EVENTUALLY HELP TO CARVE OUT A TROUGH ACROSS THE GREAT LAKES REGION...THEREBY ENCOURAGING A CHANGE TO COOLER...MORE SEASONABLE CONDITIONS. THE SWITCH TO MORE FALL-LIKE WEATHER WILL BE PERFECTLY ALIGNED WITH THE CALENDAR...AS THE LEADING EDGE TO THE COOLER CANADIAN AIRMASS WILL PRESS THROUGH OUR REGION ON LABOR DAY. UNFORTUNATELY...THIS WILL ALSO LIKELY TRANSLATE INTO A RAINY DAY FOR THOSE PLANNING OUTDOOR ACTIVITIES FOR THE TRADITIONAL END TO THE SUMMER SEASON. DIGGING INTO THE DETAILS...A LOW AMPLITUDE DIVERGENT UPPER LEVEL FLOW WILL BE FOUND OVER THE LOWER GREAT LAKES ON SATURDAY WHILE A WAVY SFC FRONTAL BOUNDARY WILL SLOWLY SETTLE ACROSS OUR FORECAST AREA. WHILE THE ASSOCIATED SYNOPTIC LIFT GENERATED FROM THIS SCENARIO WILL NOT BE VERY STRONG...IT WILL BE INTERACTING WITH AN UNSTABLE MOISTURE LADEN AIRMASS WITH PWAT VALUES IN THE VCNTY OF 1.75 INCHES. GIVEN FORECAST MUCAPE > 1000 J/KG AND A WARM CONVECTIVE CLOUD DEPTH OF OVER 10K FT...THERE WILL BE THE POTENTIAL FOR SOME HEAVY RAIN AND THUNDER. THAT BEING SAID...THERE WILL CERTAINLY BE SEVERAL RAIN FREE HOURS AS WELL. WILL THUS RAISE POPS TO LOW LIKELY. OTHERWISE...IT WILL BE YET ANOTHER WARM AND HUMID DAY WITH DEW POINTS IN THE UPPER 60S BEING ACCOMPANIED BY TEMPERATURES THAT WILL BE NEARLY 10 DEG F ABOVE NORMAL END OF AUGUST VALUES. THE DIURNALLY ASSISTED CONVECTION WILL DIE OFF ACROSS OUR REGION DURING THE FIRST HALF OF SATURDAY NIGHT...WHILE THE REMNANTS OF THE WEAK FRONTAL BOUNDARY WILL WASH OUT WITHIN THE PARALLEL MID LEVEL FLOW. SINCE THERE WILL BE NO AIRMASS CHANGE...SATURDAY NIGHT WILL ONCE AGAIN BE MUGGY WITH TEMPERATURES ONLY SETTLING INTO THE MID AND UPPER 60S. OUR ATTENTION WILL THEN GRADUALLY SHIFT TO THE UPPER GREAT LAKES... AS THE POTENT SHORTWAVE THAT IS MAKING ITS WAY ACROSS THE PACIFIC NORTHWEST THIS MORNING WILL CROSS LAKE SUPERIOR ON SUNDAY. THIS IS THE FEATURE THAT WILL ULTIMATELY END OUR STRING OF LATE SUMMER WARMTH AND HUMIDITY. AHEAD OF THIS BUNDLE OF ENERGY...WESTERN AND NORTH CENTRAL NEW YORK WILL REMAIN IN A RELATIVELY SOUPY AIRMASS ON SUNDAY BUT WITH LITTLE SYNOPTIC FORCING TO GENERATE WIDESPREAD PCPN. WHILE THE LOW LEVELS COULD BECOME QUITE UNSTABLE (TO THE TUNE OF SBCAPES >2000 J/KG)...THERE IS A SUGGESTION BY THE VARIOUS GUIDANCE PACKAGES THAT THERE WILL BE SOME MID LEVEL DRYING...BUT MORE IMPORTANTLY...THE PRESENCE OF A MID LEVEL CAP. THIS COULD BE ENOUGH TO INHIBIT THE DEVELOPMENT OF CONVECTION...ESPECIALLY OVER THE FAR WESTERN COUNTIES. FROM THE FINGER LAKES EASTWARD...THE ABOVE MENTIONED MID LEVEL DRYING AND ASSOCIATED CAP IS NOT BEING ADVERTISED AND THERE COULD BE SOME RESIDUAL LOW LEVEL CONVERGENCE IN THE VCNTY OF THE WASHED OUT FRONTAL BOUNDARY...SO WILL USE LOW CHC POPS IN THE WEST AND GRADUATE TO HIGHER LEVELS FURTHER EAST. OTHERWISE IT WILL CONTINUE TO BE WARM AND HUMID OVER OUR REGION. ON SUNDAY NIGHT...THE STRONG SHORTWAVE OVER THE UPPER GREAT LAKES WILL BE ACCOMPANIED BY A CONSOLIDATING SFC LOW IN THE VCNTY OF LOWER MICHIGAN. THIS WILL PROMOTE STRONG FRONTOGENESIS ACROSS THE UPPER MID WEST...WHILE LOW AND MID LEVEL MOISTURE WILL POOL ACROSS OUR FORECAST AREA. THIS COULD HELP TO HOLD TEMPERATURES IN THE 70S ACROSS THE LAKE PLAINS FOR THE OVERNIGHT...WITH JUST THE CHANCE FOR A SHOWER OR THUNDERSTORM. THE VAST MAJORITY OF THE NIGHT SHOULD BE RAIN FREE THOUGH. LABOR DAY WILL LIKELY BE QUITE UNSETTLED AS A 1000MB SFC LOW IS FORECAST TO LIFT BY JUST TO OUR WEST...ACROSS SOUTHERN ONTARIO. THE ASSOCIATED COLD FRONT WILL BE PUSHED ACROSS OUR REGION AND THROUGH A HUMID UNSTABLE AIRMASS IN THE PROCESS. WHILE THE JET DYNAMICS ARE NOT OVERLY IMPRESSIVE WITH THIS EVENT...THERE WILL CERTAINLY BE STRONG ENOUGH DYNAMICS IN PLACE TO AT LEAST WARRANT LIKELY POPS FOR SHOWERS AND THUNDERSTORMS. ONCE AGAIN...THERE WILL BE THE POTENTIAL FOR SOME HEAVY RAIN FROM THIS CONVECTION...ESPECIALLY IF THE FRONTAL PASSAGE HOLDS OFF UNTIL THE AFTERNOON HOURS. WILL RAISE POPS FROM 60 TO 70 REGIONWIDE. AS THE PARENT SFC LOW LIFTS ACROSS WESTERN QUEBEC AND ITS ATTENDANT COLD FRONT PUSHES OFF TO OUR EAST MONDAY NIGHT...DRIER COOLER AIR WILL SWEEP ACROSS OUR FORECAST AREA. THIS WILL PROMOTE AT LEAST PARTIAL CLEARING WITH NOTHING MORE THAN SOME LEFTOVER SHOWERS DURING THE EVENING. TEMPERATURES MONDAY NIGHT WILL DROP INTO THE 50S IN MANY AREAS...WHICH WILL BE AT SOME 10 DEGREES LOWER THAN THOSE FROM THE PREVIOUS WEEK. && .LONG TERM /TUESDAY THROUGH THURSDAY/... THERE IS NO DOUBT THAT IT WILL BE COOLER DURING THIS PERIOD. THE MEDIUM RANGE OPERATIONAL AND ENSEMBLE MODELS ARE IN STRONG AGREEMENT THAT AN ANOMALOUSLY STRONG RIDGE WILL BE PARKED OVER THE WESTERN STATES WHILE A LONGWAVE TROUGH WILL BE POSITIONED OVER EASTERN CANADA. FOR OUR FORECAST AREA...THIS WILL RESULT IN A TWO TO THREE DAY FEED OF AIR OUT OF CENTRAL CANADA...WHICH WILL INCLUDE H85 TEMPS IN THE VCNTY OF 10C. WHILE THIS WILL MAKE IT MORE COMFORTABLE ACROSS OUR REGION...TEMPERATURES WILL ACTUALLY AVERAGE CLOSE TO WHERE SHOULD BE FOR THE START OF SEPTEMBER. IN TERMS OF THE DETAILS...WILL LEAN MORE HEAVILY ON THE ECMWF PACKAGE WHICH HAS CONSISTENTLY BEEN QUITE AGGRESSIVE WITH THE PRESENCE OF A VERY ROBUST SHORTWAVE OVER CENTRAL CANADA. THIS FEATURE IS EXPECTED TO PUSH A REINFORCING SHOT OF COOL AIR ACROSS OUR REGION AT THE END OF THIS PERIOD (THURS)...WHILE THE GFS SHUNTS THE SAME AIRMASS ACROSS EASTERN QUEBEC. BEFORE WE GET TO THIS POINT IN THE FORECAST THOUGH...EXPANSIVE HIGH PRESSURE WILL MOVE FROM THE UPPER MISSISSIPPI VALLEY TO THE MID WESTERN STATES ON TUESDAY WHILE THE BASE OF A H5 TROUGH WILL CROSS LAKE ONTARIO. WHILE THERE WILL BE SOME LIMITED LOW LEVEL MOISTURE TO WORK WITH...THE AIRMASS SHOULD CAPPED ENOUGH TO ONLY WARRANT SLGT CHC POPS. WILL CALL IT SPRINKLES AND FAVOR MORE OF A STRATO-CU AFTERNOON WITH TEMPERATURES TOPPING OUT IN THE UPPER 60S AND LOWER 70S. THE SFC HIGH WILL SETTLE TO THE SOUTH ACROSS THE SRN APPALACHIANS ON WEDNESDAY...WHILE A POTENT COLD FRONT WILL CROSS THE UPPER GREAT LAKES. THIS SHOULD ALLOW FOR A SUN FILLED DAY ACROSS OUR REGION WITH AFTERNOON TEMPS GENERALLY IN THE LOWER 70S. THE COLD FRONT WILL DROP ACROSS OUR FORECAST AREA WEDNESDAY NIGHT...POSSIBLY PRODUCING A QUICK ROUND OF SHOWERS IN THE PROCESS. IN THE WAKE OF THE COLD FRONT...A DEEP UPPER LEVEL TROUGH WILL SWING ACROSS LAKE ONTARIO AND THE ST LAWRENCE VALLEY ON THURSDAY WHILE THE NEXT CANADIAN SFC HIGH WILL BUILD EAST ACROSS THE UPPER LAKES. H85 TEMPS IN THE WAKE OF THIS FRONT ARE EXPECTED TO BE IN THE LOWER SINGLE DIGITS...SO THURSDAY WILL HAVE THE POTENTIAL TO BE QUITE COOL WITH TEMPERATURES POSSIBLY NOT MAKING IT OUT OF THE 60S. && .AVIATION /08Z FRIDAY THROUGH TUESDAY/... FOR THE BALANCE OF THE NIGHT...EXPECT AREAS OF FOG AND LOW STRATUS TO CONTINUE FORMING GIVEN CONTINUED MAINLY CLEAR SKIES AND LIGHT WINDS. WHILE FOG CANNOT BE COMPLETELY RULED OUT AT ANY GIVEN LOCATION...THE GREATEST POTENTIAL FOR LIFR/IFR CONDITIONS IS EXPECTED FROM THE WESTERN SOUTHERN TIER NORTHEASTWARD ACROSS THE FINGER LAKES AND NORTH COUNTRY...WHERE DEWPOINT DEPRESSIONS ARE CURRENTLY RUNNING THE LOWEST. ACROSS THE REMAINDER OF THE REGION...A SLIGHTLY DRIER BOUNDARY LAYER SHOULD RESULT IN CONDITIONS REMAINING IN THE MVFR TO VFR RANGE. ONCE WE GET INTO THE DAYLIGHT HOURS...ANY FOG/STRATUS WILL MIX OUT BY MID TO LATE MORNING WITH RENEWED HEATING. OTHERWISE...EXPECT VFR CONDITIONS UNDER INCREASING AMOUNTS OF MID AND HIGH LEVEL CLOUDINESS IN ADVANCE OF THE NEXT SHORTWAVE/SURFACE LOW DROPPING ACROSS THE CENTRAL AND UPPER GREAT LAKES. THESE FEATURES WILL EVENTUALLY GET CLOSE ENOUGH TO BRING A RISK OF SOME SCATTERED CONVECTION TO THE SAINT LAWRENCE VALLEY AND PORTIONS OF THE NORTH COUNTRY LATER TODAY...AND TO THE REMAINDER OF THE REGION TONIGHT. OUTLOOK... SATURDAY...SHOWERS AND THUNDERSTORMS BECOMING LIKELY WITH VFR CONDITIONS LOWERING TO IFR/MVFR. SUNDAY...MAINLY VFR...WITH A CHANCE OF IFR/MVFR IN SCATTERED SHOWERS AND THUNDERSTORMS. MONDAY...SHOWERS AND THUNDERSTORMS LIKELY WITH ASSOCIATED IFR/MVFR. TUESDAY...MAINLY VFR WITH A CHANCE OF A BRIEF SHOWER. && .MARINE... WITH A WARM AIRMASS OVER THE LAKES AND ONLY A WEAK TO MODEST PRESSURE GRADIENT IN PLACE...WINDS AND WAVES SHOULD REMAIN BELOW ADVISORY LEVELS THROUGH SUNDAY. THIS SAID...SCATTERED THUNDERSTORMS COULD STILL RESULT IN LOCALLY HIGHER WINDS AND WAVES FROM LATE THIS AFTERNOON ON THROUGH THE WEEKEND. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...JJR NEAR TERM...JJR SHORT TERM...RSH LONG TERM...RSH AVIATION...JJR MARINE...JJR  FXUS61 KBUF 161839 AFDBUF AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BUFFALO NY 239 PM EDT WED OCT 16 2013 .SYNOPSIS... A BATCH OF SHOWERS AND POSSIBLE THUNDERSTORMS IS LIKELY LATER THIS AFTERNOON THROUGH THE FIRST HALF OF TONIGHT AS A COLD FRONT PUSHES ACROSS WESTERN AND NORTH CENTRAL NEW YORK. NOTICEABLY COOLER AIR WILL FOLLOW THE FRONT THROUGH THE END OF THE WEEK INTO THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... A BATCH OF SHOWERS IS LIKELY THIS AFTERNOON AS THE COLD FRONT MOVE INTO FAR WESTERN NEW YORK. THE LATEST STABILITY INDICES SUGGEST THAT THE ATMOSPHERE MAY BECOME UNSTABLE ENOUGH TO GENERATE A FEW THUNDERSTORMS AS WELL. BASIN AVERAGE QPF IS EXPECTED TO RANGE FROM ABOUT 0.25 TO 0.5 INCH WITH THE PCPN THAT FALLS TODAY. OF COURSE...HIGHER AMOUNTS ARE POSSIBLE WITH ANY THUNDERSTORMS THAT DEVELOP. ONGOING SHOWERS AND POSSIBLE THUNDERSTORMS WILL CONTINUE THIS EVENING INTO THE FIRST HALF OF TONIGHT AS THE COLD FRONT WORKS EAST ACROSS CENTRAL NEW YORK. ADDITIONAL LARGE SCALE LIFT WILL BE GENERATED BY A MID LEVEL SHORT WAVE TROUGH THAT WILL PASS JUST NORTH OF NEW YORK STATE. SHOWERS WILL TAPER OFF FROM WEST TO EAST DURING THE SECOND HALF OF THE NIGHT AS THE FRONT PUSHES INTO EASTERN NEW YORK STATE. THE EXCEPTION TO THIS GENERAL TREND WILL BE EAST OF THE LAKES WHERE FAVORABLE TEMPERATURE PROFILES AND LINGERING LOW LEVEL MOISTURE WILL LEAD TO SOME LAKE EFFECT RAIN SHOWERS. RELATIVELY MILD TEMPERATURES WILL CONTINUE THROUGH MOST OF THE DAY...BEFORE THE TRANSITION TO MORE SEASONABLE CONDITIONS BEGINS TONIGHT. && .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/... A BROAD...FULL LATITUDE TROUGH WILL DOMINATE MUCH OF NORTH AMERICA DURING THIS PERIOD...WHILE A PAIR OF ROBUST SHORTWAVES WILL KEEP A FAIR AMOUNT OF UNSETTLED WEATHER ACROSS OUR IMMEDIATE FORECAST AREA. THE HIGH AMPLITUDE FLOW WILL CERTAINLY BE MORE FALL LIKE THAN WHAT WE HAVE EXPERIENCED THE PAST SEVERAL WEEKS WITH TEMPERATURES FINALLY AVERAGING WITHIN A FEW DEGREES OF SEASONAL NORMALS. THE DETAILS... A POTENT SHORTWAVE THAT GENERATED SOME SNOW ACROSS PARTS OF NEW MEXICO AND TEXAS THIS MORNING WILL LIFT OUT ACROSS THE CENTRAL PLAINS TONIGHT AND THE MID WESTERN STATES ON THURSDAY MORNING BEFORE CROSSING OUR REGION THURSDAY NIGHT. THIS FEATURE WILL GENERATE A QUARTER TO A HALF INCH OF RAIN ACROSS WESTERN AND NORTH CENTRAL NEW YORK...WITH MARGINALLY CHILLY AIR SUPPORTING A LITTLE LAKE ENHANCEMENT EAST OF BOTH LAKES. HAVE RAISED LIKELY TO CAT POPS TO 100 REGIONWIDE. THE BULK OF THE RAIN WILL COME LATE THURSDAY AFTERNOON THROUGH THE FIRST HALF OF THURSDAY NIGHT. LOW LEVEL RIDGING AND A WEALTH OF MID LEVEL DRYING WILL WORK ACROSS OUR REGION IN THE WAKE OF THE EXITING SHORTWAVE ON FRIDAY SO THAT THE BULK OF ANY LEFTOVER SHOWERS SHOULD END BY MID MORNING. THE EXCEPTION WILL EAST OF BOTH LAKES WHERE SOME MINOR LAKE SHOWERS WILL TAKE A FEW MORE HOURS TO PETER OUT. THE DAY SHOULD END UP BEING PARTLY SUNNY FOR MOST SITES...WITH TEMPERATURES PEAKING BETWEEN 55 AND 60. AN INNOCENT LOOKING SHORTWAVE CROSSING THE WEST COAST RIDGE... 'VISIBLE' ONLY AS AN OBSCURE PATCH OF WV BRIGHTNESS OVER THE YUKON...WILL EVENTUALLY SPIN UP INTO AN IMPRESSIVE SHORTWAVE EARLY IN THE WEEKEND AS IT LIFTS OUT OF THE BASE OF THE ENTRENCHED LONG WAVE TROUGH. WHILE ITS SFC REFLECTION WILL ONLY BE AN INVERTED TROUGH NOSING NORTH OUT OF THE OHIO VALLEY...AN ANOMALOUSLY STRONG 130KT H25 JET WILL HELP IT TO PRODUCE A SWATH OF RAIN THAT SHOULD STRETCH ACROSS THE BULK OF OUR FORECAST AREA SATURDAY AND PART OF SATURDAY NIGHT. THE MOISTURE WILL BE ENHANCED BY MARGINALLY UNSTABLE AIR OVER THE LOWER LAKES...WHERE CONVECTIVE CLOUD DEPTHS WILL LIKELY EXCEED 20K FT. THIS HAS THE MAKINGS OF A SIGNIFICANT RAINFALL EVENT NORTHEAST OF BOTH LAKES...WHERE IF ALL THE INGREDIENTS COME TOGETHER...AMOUNTS OF AN INCH OR MORE WOULD NOT BE OUT OF THE QUESTION. ONCE THE SHORTWAVE PASSES SATURDAY EVENING...A WELL ALIGNED SOUTHWEST FLOW SHOULD SUPPORT A BAND OF LAKE EFFECT RAIN SHOWERS FROM LAKE ERIE AND THE IAG FRONTIER TO THE EASTERN LAKE ONTARIO REGION. THE SYNOPTIC RAINS WILL TAPER OFF ELSEWHERE. && .LONG TERM /SUNDAY THROUGH TUESDAY/... A HIGHLY POSITIVE PNA PATTERN WILL BE IN PLACE ACROSS NORTH AMERICA DURING THIS PERIOD...AS STRONG RIDGING IN THE PACIFIC NORTHWEST WILL BECOME EVEN MORE AMPLIFIED WHILE A POLAR VORTEX WILL SWING THROUGH THE BASE OF A DEEP TROUGH IN EASTERN CANADA. THIS WILL INITIALLY SET UP A FEED OF SUB-ARCTIC AIR ACROSS THE NORTHERN PLAINS AND UPPER GREAT LAKES...WITH THE COLD AIR EVENTUALLY BEING DIRECTED ACROSS SOUTHERN ONTARIO AND THE LOWER GREAT LAKES AS WE PUSH INTO THE MIDDLE PORTION OF NEXT WEEK. && .AVIATION /19Z WEDNESDAY THROUGH MONDAY/... EXPECT MOSTLY VFR CONDITIONS TO PREVAIL EARLY THIS MORNING AS A DOWNSLOPING SOUTHERLY FLOW REMAINS IN PLACE. SHOWERS DEVELOPING AHEAD OF THE APPROACHING COLD FRONT WILL CONTINUE TO SPREAD EAST ACROSS THE AREA THIS MORNING. THE BACK EDGE OF THE STEADIER SHOWERS IS GETTING CLOSE TO WESTERN NEW YORK. AS A RESULT... WE SHOULD SEE A COUPLE OF HOURS OF DRY WEATHER LATER THIS MORNING INTO THE EARLY AFTERNOON. AFTER THAT...ANOTHER ROUND OF SHOWERS AND POSSIBLE THUNDERSTORMS IS POSSIBLE LATER THIS AFTERNOON INTO THE EVENING AS THE FRONT INTERACTS WITH THE MOIST AND SOMEWHAT UNSTABLE AIR THAT WILL BE IN PLACE. MVFR CONDITIONS ARE EXPECTED WITH THIS BATCH OF SHOWERS. DRIER AIR FOLLOWING THE COLD FRONT WILL ALLOW CONDITIONS TO IMPROVE TO VFR FROM WEST TO EAST LATER TONIGHT. OUTLOOK... THURSDAY...MAINLY VFR LOWER TO MVFR LATE IN THE DAY. FRIDAY THROUGH SUNDAY...MAINLY VFR WITH A CHANCE OF SHOWERS. && .MARINE... MODERATELY STRONG SOUTHERLY WINDS AHEAD OF AN APPROACHING COLD FRONT WILL PRODUCE SMALL CRAFT ADVISORY CONDITIONS ALONG THE EASTERN SHORES OF BOTH LAKES THIS AFTERNOON. A COLD FRONT WILL CROSS LAKE ERIE THIS AFTERNOON...THEN PUSH LAKE ONTARIO LATER THIS AFTERNOON AND EVENING. THE WINDS SHIFT TO THE WEST BEHIND THE FRONT...WHILE COLDER AIR DEEPENS ACROSS THE LOWER LAKES. THIS WILL CAUSE SCA CONDITIONS TO LINGER ALONG THE EASTERN SHORES OF THE LAKES THROUGH TONIGHT AND INTO THURSDAY MORNING ON LAKE ONTARIO. HIGH PRESSURE BUILDING ACROSS THE NATIONS MIDSECTION WILL MAINTAIN A WESTERLY FLOW WITH PERIODIC BREEZY CONDITIONS DURING THE AFTERNOONS THROUGH THE WEEK. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT THURSDAY FOR LEZ040-041. SMALL CRAFT ADVISORY UNTIL 11 AM EDT THURSDAY FOR LOZ045. SMALL CRAFT ADVISORY FROM 2 AM TO 11 AM EDT THURSDAY FOR LOZ044. && $$ SYNOPSIS...TJP NEAR TERM...TJP SHORT TERM...RSH LONG TERM...RSH AVIATION...TJP MARINE...TJP  FXUS61 KBUF 120905 AFDBUF AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BUFFALO NY 405 AM EST THU DEC 12 2013 .SYNOPSIS... A VERY COLD AIRMASS WILL REMAIN IN PLACE OVER EASTERN CANADA AND THE GREAT LAKES REGION THROUGH FRIDAY...AND THIS WILL CONTINUE TO SUPPORT IMPRESSIVE PLUMES OF LAKE EFFECT SNOW. WHILE THE LAKE SNOWS WILL TAPER OFF AS WE HEAD INTO THE UPCOMING WEEKEND...A STORM SYSTEM PASSING OVER THE MID ATLANTIC STATES WILL PRODUCE A WIDESPREAD ACCUMULATING SNOWFALL ACROSS OUR FORECAST AREA SATURDAY AND SATURDAY NIGHT. TEMPERATURES ARE EXPECTED TO REMAIN BELOW NORMAL THROUGH AT LEAST MONDAY. && .NEAR TERM /THROUGH TONIGHT/... A REINFORCING SHOT OF COLD AIR PUSHED SOUTH ACROSS THE REGION OVERNIGHT...AND THIS DISRUPTED THE WELL ORGANIZED AND IMPRESSIVE LAKE SNOW PLUMES THAT HAS PREVIOUSLY PRODUCED 2 TO 3 FEET EAST OF LAKES ERIE AND ONTARIO. THE BAND OFF LK ONTARIO SAGGED SOUTH OF THE LAKE SHORE AND BROUGHT A FEW INCHES OF SNOW TO THE LAKE SHORE COUNTIES...WHILE THE SNOWS OFF LK ERIE WERE NOTABLY WEAKER AND LESS ORGANIZED OVER A LARGE PERCENTAGE OF THE WRN SOUTHERN TIER. DURING THE COURSE OF THIS MORNING THOUGH...THE LOW LEVEL FLOW WILL BECOME BETTER ALIGNED WITH A RISING CAP SUPPORTING RENEWED PLUMES OF MODERATE TO HEAVY LAKE SNOW. THESE PLUMES WILL LIFT NORTH DURING THE MIDDAY INTO THE EARLY EVENING HOURS...WITH HEAVY SNOWS APPROACHING BOTH BUFFALO AND WATERTOWN. GETTING INTO SOME SPECIFICS... OFF LAKE ERIE... MODERATE TO EXTREME INSTABILITY WILL BE IN PLACE OVER THE LAKE TODAY WITH MODERATELY SHEARED 280 FLOW PRODUCING MULTIPLE BANDS OF LIGHT TO MODERATE SNOW OVER THE MAJORITY OF THE WESTERN SOUTHERN TIER. SEVERAL INCHES OF FRESH SNOW WILL FALL BY LUNCHTIME...MAINLY SOUTH OF THE BOSTON HILLS. AS WE PROGRESS THROUGH THE AFTERNOON...THE LAKE SNOWS WILL CONSOLIDATE INTO A PLUME OF HEAVY LAKE SNOW THAT WILL LIFT ACROSS THE SOUTHERN HALF OF ERIE COUNTY...LIKELY IMPACTING THE SOUTH TOWNS (ORCHARD PARK/EAST AURORA) AND THE SOUTHERN BUFFALO SUBURBS LATE IN THE AFTERNOON AND PARTICULARLY DURING THE EVENING RUSH HOUR. SNOWFALL RATES OF 1 TO 3 INCHES AN HOUR WILL BE POSSIBLE WITH THIS ACTIVITY...WITH THE NORTHERN PORTION OF THE BAND POSSIBLY REACHING BUFFALO AND ITS EASTERN SUBURBS DURING THE EARLY EVENING HOURS. VERY DIFFICULT DRIVING CONDITIONS ARE EXPECTED FOR THE EVENING RUSH HOUR...PARTICULARLY SOUTH AND EAST OF DOWNTOWN BUFFALO. AS WE WORK THROUGH TONIGHT...THE STEERING WINDS WILL VEER TO ABOUT 280 DEGREES WITH THE STEADY HEAVY LAKE SNOWS DROPPING BACK SOUTH ACROSS THE SOUTHERN HALF OF THE COUNTY. WHILE CONDITIONS WILL IMPROVE IN THE BUFFALO METRO AREA...TREACHEROUS DRIVING CONDITIONS WILL BECOME RE ESTABLISHED OVER SOUTHERN ERIE COUNTY AND PORTIONS OF NORTHERN CHAUTAUQUA AND NORTHWESTERN CATTARAUGUS COUNTIES WHERE FRESH SNOWFALL ACCUMULATIONS COULD APPROACH A FOOT. THROUGH THIS 12 HOUR PERIOD...IT WILL LIKELY BE TOO COLD TO ALLOW FOR SIGNIFICANT MIXED PHASE CLOUD DEPTH OFF LK ERIE...SO AM NOT ANTICIPATING ANY LAKE INDUCED THUNDERSNOW. OFF LAKE ONTARIO... THE ONCE IMPRESSIVE SNOW BAND THAT WAS PRODUCING SNOW AT A RATE OF UP TO 4 INCHES PER HOUR IS A MERE SHELL OF ITSELF EARLY THIS MORNING AS A NOTABLY LOWER CAP AND A SOUTHWARD SHIFT OF THE CONVERGENCE ZONE OFF THE LAKE HAS LED TO WEAKER CONVECTION. A BAND STRETCHING ACROSS THE SOUTH SHORE COUNTIES FROM NEAR THIRTY MILE POINT TO THE NORTHERN SUBURBS OF ROCHESTER TO WAYNE AND NORTHERN CAYUGA COUNTIES WILL LIFT BACK TO THE NORTH OVER THE NEARSHORE WATERS AS THE MORNING MATURES. BY LUNCHTIME...A RISING CAP AND A REALIGNING 270 FLOW WILL DIRECT A CONSOLIDATING BAND OF MODERATE TO HEAVY LAKE EFFECT SNOW OVER THE TUG HILL...WITH SNOW FALL RATES ONCE AGAIN INCREASING TO MORE THAN AN INCH PER HOUR FORECAST THROUGH THE AFTERNOON. LATE TODAY AND EARLY TONIGHT...THE BAND MAY LIFT TO BETWEEN WATERTOWN AND THE TUG HILL BEFORE SETTLING BACK TO THE SOUTH ACROSS THE TUG DURING THE OVERNIGHT HOURS. WITH A CAP APPROACHING 15K FT... IT IS NOT OUT OF THE QUESTION THAT A LIMITED MIXED PHASE CLOUD LAYER COULD INDUCE A BIT OF LIGHTNING...BUT AGAIN...THIS SPECIFIC EVENT IS ON THE COLD SIDE FOR LAKE INDUCED ELECTRIFICATION. FRESH SNOWFALL ACROSS THE TUG HILL IS EXPECTED TO RANGE FROM ONE TO TWO FEET LATER TODAY AND TONIGHT...SO VERY DIFFICULT TRAVEL CONDITIONS CAN ONCE AGAIN BE EXPECTED ON I-90 BETWEEN THE I-81 EXCHANGE AND WATERTOWN. OUTSIDE THE LAKE BANDS...IT WILL EB QUITE COLD TODAY AND TONIGHT WITH FLURRIES AND SCATTERED SNOW SHOWERS. TEMPERATURES WILL BE SOME 10 TO 15 DEG F BELOW NORMAL WITH HIGHS TODAY WILL ONLY REACH INTO THE TEENS TO NEAR 20. WIND CHILL VALUES WILL BE WITHIN A FEW DEGREES OF ZERO. && .SHORT TERM /FRIDAY THROUGH SUNDAY/... DURING THE COURSE OF FRIDAY...LOW PRESSURE OVER NEW ENGLAND WILL EXIT EASTWARD ACROSS THE CANADIAN MARITIMES...WHILE DRAGGING ITS TRAILING COLD FRONT SOUTHWARD ACROSS NEW YORK STATE. AS A RESULT... SIGNIFICANT LAKE SNOWS STILL ONGOING EAST OF THE LAKES AT THE START OF THE DAY WILL GET SHUNTED SOUTHWARD AND WEAKEN DRAMATICALLY AS THE LOW LEVEL FLOW VEERS MORE NORTHERLY AND MUCH DRIER AIR/A LOWERING CAP GETS INTRODUCED BEHIND THE SURFACE BOUNDARY...THOUGH NOT BEFORE DROPPING AT LEAST SOME ADDITIONAL ADVISORY-TYPE ACCUMULATIONS EAST OF THE LAKES. THE DIMINISHING TREND WILL AFFECT THE LAKE ONTARIO LAKE SNOWS FIRST...WITH THE LAKE EFFECT BAND INITIALLY GETTING SHUNTED SOUTH ACROSS MUCH OF THE SOUTH SHORE OF THE LAKE AND DROPPING SOME ADDITIONAL MINOR ACCUMS OF 1-3 INCHES ACROSS THE NIAGARA-CAYUGA COUNTY CORRIDOR...BEFORE RAPIDLY BREAKING UP AS IT IS PUSHED FURTHER INLAND AND AWAY FROM ITS MOISTURE SOURCE. MEANWHILE...THE LAKE ERIE ACTIVITY WILL HANG ON A BIT LONGER GIVEN THE LATER ARRIVAL OF THE FRONT...BUT EVEN THIS SHOULD WEAKEN NOTICEABLY DURING THE LATE MORNING AND AFTERNOON. OUTSIDE OF THE MAIN LAKE EFFECT AREAS...GENERALLY JUST EXPECT SOME SCATTERED SNOW SHOWERS AND MINOR ACCUMS OF AN INCH OR LESS IN CONJUNCTION WITH THE FRONTAL PASSAGE. GIVEN THE FROPA...TEMPS SHOULD EXHIBIT A NON- DIURNAL TREND...WITH MORNING HIGHS RANGING FROM THE MID-UPPER TEENS ACROSS THE NORTH COUNTRY TO THE LOWER-MID 20S ELSEWHERE...THEN SLOWLY DROPPING OFF DURING THE AFTERNOON. FRIDAY NIGHT...LOW LEVEL-RIDGING EXTENDING EAST ACROSS NEW YORK STATE AND NEW ENGLAND WILL BRING A RELATIVE MINIMUM IN SNOWFALL CHANCES DURING THE EVENING...BEFORE INCREASING WARM ADVECTION/ MOISTURE ASSOCIATED WITH DEVELOPING LOW PRESSURE OVER THE TENNESSEE VALLEY BRINGS A RENEWED POTENTIAL FOR SOME LIGHT SNOW TO AREAS SOUTH OF LAKE ONTARIO OVERNIGHT. GIVEN WHAT SHOULD BE COLDER AIR AND LESS CLOUD COVER OVER THE NORTH COUNTRY COMPARED TO AREAS SOUTH OF LAKE ONTARIO...NIGHTTIME LOWS WILL EXHIBIT A DECENT NORTH-SOUTH GRADIENT...WITH READINGS RANGING FROM THE TEENS SOUTH OF THE LAKE TO BETWEEN ZERO AND 10 BELOW ACROSS THE NORTH COUNTRY. SATURDAY THROUGH SUNDAY...OUR ATTENTION WILL SHIFT BACK TO THE SYNOPTIC SCALE AS THE AFOREMENTIONED SURFACE LOW OVER THE TENNESSEE VALLEY REDEVELOPS OFF THE MID ATLANTIC COASTLINE...THEN LIFTS NORTHEASTWARD AND OUT INTO THE WESTERN ATLANTIC...WHILE A WEAKER LOW DRIFTS ACROSS THE GREAT LAKES. THE WARM AIR ADVECTION PATTERN IN ADVANCE OF THE MAIN SURFACE LOW WILL SPREAD A SHOT OF PLENTIFUL MOISTURE AND LIFT ACROSS OUR REGION SATURDAY AND SATURDAY EVENING...WITH THIS THEN EXITING OFF TO OUR NORTH AND EAST LATER SATURDAY NIGHT AND SUNDAY MORNING. WITH OUR AIRMASS LIKELY REMAINING COLD ENOUGH FOR ALL SNOW....THIS SYSTEM SHOULD BRING A WIDESPREAD GENERAL SNOWFALL TO THE AREA BETWEEN SATURDAY AND THE FIRST PART OF SUNDAY. WHILE THE EXACT ACCUMS WE CAN EXPECT OUT OF ALL THIS ARE STILL UNCERTAIN...AT THIS POINT A 00Z OPERATIONAL MODEL SUITE/WPC BLEND SUGGESTS THE POTENTIAL FOR A DECENT ADVISORY-TYPE SNOWFALL AREAWIDE. TEMPERATURE- WISE...READINGS SHOULD REMAIN BELOW AVERAGE RIGHT THROUGH THE WEEKEND...WITH HIGHS GENERALLY IN THE UPPER TEENS TO MID 20S SATURDAY AND SUNDAY...AND NIGHTTIME LOWS DIPPING INTO THE 10-20 RANGE SATURDAY NIGHT. && .LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/... ONCE THIS WEEKEND'S SYNOPTIC SYSTEM LIFTS OFF TO THE NORTHEAST... ANOTHER SHOT OF COLD AIR WILL PUSH INTO THE REGION WITH LAKE SNOWS REDEVELOPING ON A WEST-NORTHWESTERLY FLOW...WITH THE BEST POTENTIAL FOR THESE COMING BETWEEN SUNDAY NIGHT AND MONDAY MORNING. AFTER THIS...HIGH PRESSURE RIDGING ACROSS THE REGION SHOULD BRING DIMINISHING LAKE EFFECT POTENTIAL MONDAY AFTERNOON AND NIGHT... BEFORE THE NEXT CLIPPER SYSTEM CROSSES THE GREAT LAKES TUESDAY AND WEDNESDAY. && .AVIATION /09Z THURSDAY THROUGH MONDAY/... LAKE EFFECT SNOW BANDS EAST OF LAKES ERIE AND ONTARIO ARE BECOMING SLIGHTLY MORE NORTHWEST TO SOUTHEASTERLY...ESPECIALLY OFF LAKE ONTARIO. THIS WILL DIRECT THE LAKE SNOWS INTO THE KJHW LOCALE WITH LOWER MVFR OR IFR CONDITIONS THROUGH THE REMAINDER OF THE PRE DAWN HOURS. A WEST TO SLIGHTLY SOUTHWESTERLY REORIENTATION OF THE BOUNDARY LAYER WINDS AND ASSOCIATED LAKE EFFECT SNOW BANDS MAY BRING IFR CONDITIONS BACK TO KBUF DURING THURSDAY AFTERNOON AND EVENING...MAINLY 21Z THROUGH 01Z...AND MORE ESPECIALLY TO KART FROM 17Z ONWARD AND HEAVIER SNOW WITH LIFR POSSIBLE AFTER 00Z FRIDAY. OUTLOOK... THURSDAY AFTERNOON AND FRIDAY...MAINLY VFR...EXCEPT IFR IN LAKE EFFECT SNOW SHOWERS EAST OF THE LAKES. SATURDAY AND SUNDAY...MVFR/IFR WITH SNOW LIKELY. MONDAY...MVFR WITH A CHANCE FOR SNOW SHOWERS. && .MARINE... WITH A DEEP POOL OF COLD AIR OVER THE EASTERN GREAT LAKES RIGHT INTO THE WEEKEND...AND PASSAGE OF SEVERAL SURFACE WAVES/LOW PRESSURES ACROSS THE GREAT LAKES SOLID ADVISORY-LEVEL CONDITIONS WILL PERSIST THROUGH THE END OF THE WEEK. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...LAKE EFFECT SNOW WARNING FROM 10 AM THIS MORNING TO 1 PM EST FRIDAY FOR NYZ007-008-012-019-020-085. LAKE EFFECT SNOW WARNING UNTIL 4 PM EST FRIDAY FOR NYZ006. LAKE EFFECT SNOW WARNING UNTIL 1 PM EST THIS AFTERNOON FOR NYZ005. LAKE EFFECT SNOW WARNING UNTIL 10 AM EST THIS MORNING FOR NYZ004. LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST THIS MORNING FOR NYZ003. LAKE EFFECT SNOW WARNING FROM 1 PM THIS AFTERNOON TO 5 AM EST FRIDAY FOR NYZ010. LAKE EFFECT SNOW ADVISORY FROM 10 AM THIS MORNING TO 1 AM EST FRIDAY FOR NYZ011. MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST FRIDAY FOR LEZ040-041. SMALL CRAFT ADVISORY UNTIL 7 PM EST FRIDAY FOR LOZ042>045. && $$ SYNOPSIS...RSH NEAR TERM...RSH SHORT TERM...JJR LONG TERM...JJR/TMA AVIATION...RSH MARINE...APFFEL/THOMAS  FXUS61 KBUF 130854 AFDBUF AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BUFFALO NY 354 AM EST FRI DEC 13 2013 .SYNOPSIS... AN ARCTIC COLD FRONT WILL DROP SOUTH ACROSS OUR REGION TODAY...AND THIS WILL BRING AN END TO THE SIGNIFICANT LAKE EFFECT SNOWS. A STORM SYSTEM WILL TRACK FROM THE TENNESSEE VALLEY TO THE MID ATLANTIC STATES DURING THE WEEKEND THOUGH...AND THIS WILL PRODUCE A WIDESPREAD ACCUMULATING SNOWFALL ACROSS ALL OF WESTERN AND NORTH CENTRAL NEW YORK. OTHERWISE IT WILL REMAIN VERY COLD INTO EARLY NEXT WEEK WITH TEMPERATURES AVERAGING SOME 10 TO 15 DEGREES BELOW NORMAL. && .NEAR TERM /THROUGH TONIGHT/... AFTER SEVERAL DAYS OF SIGNIFICANT...AND AT TIMES EVEN INTENSE...LAKE EFFECT SNOW...THE WEATHER ACROSS OUR REGION WILL SHIFT FROM MESOSCALE TO SYNOPTIC IN NATURE. THAT SHOULD NOT BE CONSTRUED AS GOOD NEWS THOUGH FOR THOSE THAT APPRECIATE THE MILDER WEATHER...AS IT WILL MOST CERTAINLY REMAIN QUITE COLD. AN ARCTIC COLD FRONT STRETCHING FROM THE UPPER GREAT LAKES ACROSS SOUTHERN ONTARIO TO THE LOWER ST LAWRENCE VALLEY WILL DROP SOUTH ACROSS OUR REGION TODAY. THIS WILL BRING AN END TO THE ON-GOING LAKE EFFECT SNOW EAST OF BOTH LAKES...BUT NOT BEFORE ANOTHER 3 TO 6 INCHES OF FRESH FLUFFY SNOW ACCUMULATES. THE TWO MAIN AREAS THAT WILL REMAIN THE TARGET OF THIS LAKE EFFECT WILL BE PARTS OF THE SRN TIER...AND FROM THE TUG HILL SOUTHWARDS ACROSS OSWEGO COUNTY TO PORTIONS OF WAYNE AND CAYUGA COUNTIES. FIRST...OFF LK ERIE... WHILE A WELL ALIGNED 280 FLOW WILL BE IN PLACE OVER THE LAKE FOR THE BULK OF TODAY...A FAIRLY PRONOUNCED CAP AROUND 6K FT WILL LIMIT THE CONVECTIVE CLOUD DEPTH. THIS SHOULD KEEP SNOWFALL RATES FROM EXCEEDING AN INCH/INCH AN HOUR...BUT THERE WILL CERTAINLY STILL BE ENOUGH SNOW TO CAUSE SOME TRAVEL PROBLEMS. UNLIKE PREVIOUS DAYS WHEN A WELL DEFINED PLUME OF SNOW WAS IN PLACE...THE LAKE SNOW EARLY THIS MORNING IS DEPICTED A MORE NEBULOUS AREA OF LIGHT SNOW OVER THE SRN TIER. THIS AREA SHOULD BLOSSOM A LITTLE AS WE MOVE INTO THE DAYLIGHT HOURS AS A DEEPER SYNOPTIC MOISTURE FIELD WILL COME INTO PLAY. THE LAKE SNOW WILL BECOME BETTER ORGANIZED WITH THE GREATEST SNOWFALL COMING BETWEEN DAYBREAK AND LUNCHTIME. DURING THE MIDDAY AND AFTERNOON...THE AFOREMENTIONED ARCTIC FRONT WILL SETTLE SOUTH ACROSS THE REGION AND DISRUPT THE LAKE INDUCED CONVECTION. THE LAKE SNOWS WILL TAPER OFF AND GRADUALLY HAND THE PCPN PROCESS OFF TO A SWATH OF SYNOPTICALLY INDUCED LOW LEVEL CONVERGENCE THAT WILL STRETCH ACROSS MUCH OF THE SRN TIER. THE RESULT WILL BE LIGHT SNOW AND FLURRIES THAT WILL INCREASE IN INTENSITY DURING THE OVERNIGHT. MORE ON THAT IN A MOMENT. NOW...OFF LK ONTARIO... AN ALL TOO FAMILIAR PLUME OF MODERATE TO HEAVY LAKE SNOW WAS FOUND OVER THE TUG HILL EARLY THIS MORNING WHERE SNOWFALL RATES OF 2 TO 3 INCHES IS BEING SUGGESTED BY THE KTYX RADAR. THIS SEEMS QUITE REASONABLE GIVEN THE TEMPS AND 30-40 DBZ REFLECTIVITY. THE LOW SHEARED 270-280 FLOW SHOULD KEEP THIS SNOWBAND IN PLACE THROUGH ABOUT DAYBREAK...AFTER WHICH TIME THE APPROACHING ARCTIC COLD FRONT WILL PUSH THE BAND SOUTH ACROSS THE SOUTHERN HALF OF OSWEGO COUNTY TO WAYNE AND NORTHERN CAYUGA COUNTIES. SNOWFALL RATES WILL LOWER AS THE BAND COMES OFF THE LAKE...BUT ENOUGH SNOW SHOULD FALL OVER PARTS OF WAYNE AND NOREEN CAYUGA COUNTY TO WARRANT A LAKE SNOW ADVISORY. THIS FLAG WILL RUN THROUGH 20Z. OUTSIDE OF THE LAKE EFFECT AREAS TODAY...IT WILL BE CLOUDY AND COLD WITH FLURRIES GIVING WAY TO SOME STEADIER SNOW SHOWERS BROUGHT ABOUT BY THE PASSAGE OF THE COLD FRONT. THESE SNOW SHOWERS COULD BRING AN INCH OR SO OF FRESH SNOW TO SITES OUTSIDE OF THE LAKE EFFECT SNOW BANDS. SLIGHTLY HIGHER AMOUNTS WILL BE POSSIBLE DUE TO A NORTHERLY UPSLOPE FLOW ACROSS THE HIGHER TERRAIN OF THE SRN TIER. TEMPERATURES WILL STRUGGLE INTO THE LOWER 20S FOR MOST AREAS BY MIDDAY...THEN WILL REMAIN NEARLY STEADY OR WILL FALL INTO THE TEENS IN THE WAKE OF THE FRONT DURING THE AFTERNOON. WIND CHILL VALUES WILL GENERALLY REMAIN IN THE SINGLE DIGITS. TONIGHT...DISORGANIZED LOW PRESSURE OVER THE CENTRAL PLAINS WILL TRACK EAST ACROSS THE LOWER MISSISSIPPI VALLEY. A CONVERGENT LOW LEVEL FLOW OVER THE SOUTHERN TIER DURING THE EVENING WILL THEN BE COMPLIMENTED WITH A LITTLE JET INDUCED LIFT DURING THE COURSE OF THE OVERNIGHT TO INITIATE A PERIOD OF STEADY LIGHT SNOW THAT WILL SPREAD TO THE NORTHEAST DURING THE COURSE OF THE OVERNIGHT. TEMPERATURES TONIGHT WILL DROP TO BETWEEN 10 AND 15 FOR MOST SITES...WITH READINGS TUMBLING BELOW ZERO ACROSS THE NORTH COUNTRY. && .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... DURING THIS PERIOD...OUR MAIN FORECAST CONCERN CONTINUES TO BE THE POTENTIAL FOR A WIDESPREAD SIGNIFICANT SNOWFALL BETWEEN SATURDAY AND SUNDAY MORNING. THE 00Z GUIDANCE SUITE REMAINS IN PRETTY GOOD AGREEMENT ON A STRONG NORTHERN STREAM SHORTWAVE OVER CENTRAL CANADA DIGGING SOUTHEAST AND LEADING TO THE DEVELOPMENT OF A CLOSED LOW SATURDAY AND SUNDAY... WHILE A SOMEWHAT WEAKER BUT STILL SIGNIFICANT SOUTHERN STREAM IMPULSE LIFTS FROM THE SOUTHERN PLAINS TO THE VIRGINIA COAST...THEN OUT INTO THE WESTERN ATLANTIC. AT THE SURFACE...AN INCIPIENT WEAK WAVE OVER THE DEEP SOUTH SATURDAY MORNING WILL LIFT NORTHEAST INTO THE OHIO VALLEY SATURDAY...BEFORE TRANSFERRING ITS ENERGY TO A RAPIDLY STRENGTHENING AND INCREASINGLY DOMINANT SECONDARY LOW TAKING SHAPE OFF THE DELMARVA COASTLINE SATURDAY NIGHT. THIS COASTAL LOW WILL THEN CONTINUE TO DEEPEN AS IT LIFTS NORTHEASTWARD JUST OFFSHORE OF THE NEW ENGLAND COAST ON SUNDAY...WHILE REMNANT SURFACE TROUGHING LINGERS ACROSS THE GREAT LAKES. IN ADVANCE OF THE FIRST WAVE LIFTING NORTHEAST INTO THE OHIO VALLEY ON SATURDAY...INCREASING WARM AIR ADVECTION/ISENTROPIC LIFT WILL SPREAD A SWATH OF FAIRLY STEADY LIGHT SNOW NORTHEASTWARD ACROSS NEW YORK STATE. THEN AS THE INITIAL LOW LIFTS INTO PA AND TRANSFERS ITS ENERGY TO THE SECONDARY COASTAL LOW SATURDAY NIGHT...OVERALL ISENTROPIC FORCING AND MOISTURE WILL BECOME MAXIMIZED ACROSS OUR AREA...WHICH SHOULD RESULT IN THE SNOW PICKING UP IN INTENSITY FOR ABOUT A 6-9 HOUR PERIOD. AFTER THIS TIME...EXPECT THE SNOW TO AGAIN BECOME LIGHTER IN NATURE AND RAPIDLY DIMINISH FROM SOUTHWEST TO NORTHEAST LATER SATURDAY NIGHT AND SUNDAY MORNING AS THE COASTAL LOW BECOMES DOMINANT AND DRAWS THE BEST FORCING AND DEEPEST MOISTURE OFF TO OUR NORTHEAST. COMPARED TO YESTERDAY...THE 00Z GUIDANCE HAS TRENDED SOMEWHAT HEAVIER WITH THE QPF FROM THIS SYSTEM...WITH A CONSENSUS OF THE MAIN OPERATIONAL MODELS AND WPC GUIDANCE NOW SUGGESTING THE POTENTIAL FOR 0.50-0.70" INCHES OF LIQUID EQUIVALENT PRECIP...WITH THE GREATEST QPF GENERALLY INDICATED ACROSS PORTIONS OF THE FINGER LAKES AND NORTH COUNTRY. USING TYPICAL SNOWFALL RATIOS FOR WARM ADVECTIVE PRECIP /WHICH ARE GENERALLY BETWEEN 10:1 AND 15:1/...SUCH QPF WOULD LIKELY TRANSLATE INTO ROUGHLY 6-9" OF SNOW FALLING OVER A 24-30 HOUR PERIOD...WITH THE GREATEST PORTION OF THIS COMING DURING SATURDAY NIGHT. TAKING INTO ACCOUNT LOCAL 24-HOUR WARNING CRITERIA...SUCH AMOUNTS WOULD GENERALLY FALL WITHIN THE UPPER END OF THE ADVISORY RANGE IF REALIZED...WITH EASTERN SECTIONS POTENTIALLY HAVING A SHOT AT LOWER-END WARNING CRITERIA SNOWFALL AMOUNTS. THE ABOVE STATED...GIVEN NOTICEABLY LOWER QPF SEEN IN PREVIOUS MODEL CYCLES...AND THE FACT THAT THE EXACT AMOUNT OF PRECIP WE'LL SEE OUT OF THIS SYSTEM WILL ULTIMATELY DEPEND UPON HOW QUICKLY ENERGY TRANSFERS FROM THE PRIMARY TO THE SECONDARY LOW /A FACTOR THAT IS NEVER EASY TO NAIL DOWN/...WE DO NOT YET HAVE ENOUGH CONFIDENCE TO JUSTIFY UPGRADING PORTIONS OF THE AREA FROM THE CURRENT BLANKET WINTER WEATHER ADVISORY TO A WINTER STORM WARNING. WITH ALL THIS IN MIND...FOR NOW WILL ELECT TO JUST STICK WITH THE EXISTING ADVISORY WHILE BUMPING UP SNOWFALL AMOUNTS TO THE HIGHER END OF THE ADVISORY RANGE...AND ALLOW THE DAY SHIFT TO PERUSE THE 06Z/12Z GUIDANCE CYCLES BEFORE MAKING A CALL ON ANY POTENTIAL ADJUSTMENTS TO OUR EXISTING HEADLINES. FOLLOWING THE DEPARTURE OF THIS SYSTEM ON SUNDAY...A BROAD WEST- NORTHWESTERLY FLOW OF COLDER AIR WILL DEVELOP...RESULTING IN THE REDEVELOPMENT OF LAKE SNOWS EAST-SOUTHEAST OF THE LAKES BY LATER IN THE AFTERNOON. WHILE OVER-LAKE INSTABILITY LOOKS TO SUFFICIENT...AT THIS POINT MOISTURE AND SHEAR PROFILES DO NOT APPEAR TO BE OVERLY FAVORABLE FOR SIGNIFICANT ACCUMULATIONS. && .LONG TERM /MONDAY THROUGH THURSDAY/... WHILE WEST TO NORTHWESTERLY FLOW LAKE EFFECT WILL LIKELY BE ONGOING AT THE START OF THE PERIOD...HIGH PRESSURE AND DRIER AIR NOSING DOWN FROM CENTRAL CANADA AND THE UPPER GREAT LAKES WILL LIKELY LIMIT SIGNIFICANT ACCUMULATIONS AS THE FAVORABLE DENDRITIC SNOW GROWTH REGION AND AVAILABLE MOISTURE DIMINISH...AND LAKE-INDUCED EQLS LOWER DRAMATICALLY. COUPLED WITH INCREASING SHEAR AND DEVELOPING WARM AIR ADVECTION IN ADVANCE OF THE NEXT APPROACHING CLIPPER SYSTEM...THIS SHOULD RESULT IN THE LAKE SNOWS WINDING DOWN BY LATER MONDAY. AFTER THAT...THE MEDIUM RANGE MODELS REMAIN IN FAIRLY CLOSE AGREEMENT ON BRINGING A CLIPPER-TYPE LOW ACROSS THE REGION IN THE MONDAY NIGHT TO TUESDAY NIGHT TIME FRAME ALONG WITH SOME LIGHT WARM ADVECTIVE SNOWS. BEHIND THIS CLIPPER...ANOTHER SHOT OF MODIFIED ARCTIC AIR MAY REINVIGORATE LAKE SNOWS ACROSS THE REGION FOR MIDWEEK...HOWEVER THIS MAY BE BRIEF AS ANOTHER CLIPPER LOW ARRIVES ON THE SCENE BY THURSDAY. && .AVIATION /09Z FRIDAY THROUGH TUESDAY/... LAKE EFFECT SNOW BANDS WILL BE THE FOCUS THIS TAF CYCLE. EXPECT IFR AND LOWER FLIGHT CONDITIONS WITHIN THE SNOW BANDS...WHILE OUTSIDE OF SNOWBANDS VFR FLIGHT CONDITIONS WILL PREVAIL. IN THE WEST...DISORGANIZED LAKE SNOWS WILL BE FOUND ACROSS THE SOUTHERN TIER. WHILE THIS ACTIVITY WILL INTENSIFY A BIT BETWEEN 12 AND 15Z...IT IS NOT EXPECTED TO BE AS SIGNIFICANT AS THE SNOWS FROM THE PAST FEW DAYS. NEVERTHELESS...IFR TO MVFR CONDITIONS CAN BE EXPECTED AT KJHW AND KELZ. ELSEWHERE...VFR CONDITIONS WILL DETERIORATE DURING THE MIDDAY AND AFTERNOON AS AN ARCTIC FRONT WILL DROP THROUGH THE REGION. EAST OF LAKE ONTARIO...A PLUME OF MODERATE TO HEAVY LAKE SNOW WILL REMAIN IN PLACE OVER THE TUG HILL PLATEAU THROUGH DAYBREAK BEFORE PUSHING SOUTH BETWEEN 12 AND 16Z. WHILE KART WILL NOT BE IMPACTED BY THIS LAKE SNOW...CONDITIONS MAY BRIEFLY DROP TO MVFR DUE TO THE FRONTAL PASSAGE. VFR CONDITIONS WILL BE FOUND AT MOST SITES FOR THE FIRST HALF OF TONIGHT...WITH THE EXCEPTION OF KJHW WHERE MVFR CIGS ARE EXPECTED. DURING THE OVERNIGHT...LIGHT SNOW WILL SPREAD NORTHEAST ACROSS THE REGION WITH MVFR CONDITIONS COMING BACK INTO PLAY. OUTLOOK... SATURDAY AND SUNDAY...IFR WITH SNOW...TAPERING OFF EARLY SUNDAY MORNING. MONDAY...MVFR WITH A CHANCE FOR SNOW SHOWERS. IFR WITH LAKE EFFECT SNOW LIKELY SOUTHEAST OF THE LAKES. TUESDAY...MVFR WITH A CHANCE OF SNOW SHOWERS. && .MARINE... WITH A DEEP POOL OF COLD AIR OVER THE EASTERN GREAT LAKES RIGHT INTO THE WEEKEND...AND PASSAGE OF SEVERAL SURFACE WAVES/LOW PRESSURES ACROSS THE GREAT LAKES SOLID ADVISORY-LEVEL CONDITIONS WILL PERSIST THROUGH THE END OF THE WEEK. THE EXCEPTION WILL BE THE EASTERN HALF OF LAKE ONTARIO WHERE GALE FORCE WINDS WILL BE PLACE THROUGH MIDDAY. WINDS ACROSS BOTH LAKES WILL GRADUALLY SUBSIDE DURING THE MIDDAY AND AFTERNOON WITH NO WIND BASED FLAGS EXPECTED BY THIS EVENING. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...WINTER WEATHER ADVISORY FROM 6 AM SATURDAY TO 6 AM EST SUNDAY FOR NYZ001>005-010>014-019>021-085. LAKE EFFECT SNOW WARNING UNTIL 1 PM EST THIS AFTERNOON FOR NYZ007-008-012-019-020-085. WINTER WEATHER ADVISORY FROM 10 AM SATURDAY TO 10 AM EST SUNDAY FOR NYZ006>008. LAKE EFFECT SNOW WARNING UNTIL 4 PM EST THIS AFTERNOON FOR NYZ006. LAKE EFFECT SNOW ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR NYZ004-005. MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST THIS MORNING FOR LEZ020. SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR LEZ040-041. SMALL CRAFT ADVISORY UNTIL 7 AM EST THIS MORNING FOR LOZ030. SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR LOZ042. GALE WARNING UNTIL 10 AM EST THIS MORNING FOR LOZ043>045- 063>065. && $$ SYNOPSIS...RSH NEAR TERM...RSH SHORT TERM...JJR LONG TERM...JJR/TMA AVIATION...RSH MARINE...RSH  FXUS61 KBUF 240828 AFDBUF AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BUFFALO NY 428 AM EDT TUE JUN 24 2014 .SYNOPSIS... LOW PRESSURE WILL MOVE THROUGH THE CENTRAL GREAT LAKES SENDING A SLOW MOVING COLD FRONT TOWARDS THE REGION TODAY. SHOWERS AND THUNDERSTORMS WILL BE LIKELY THIS AFTERNOON THROUGH WEDNESDAY. THE FRONT WILL PASS THROUGH THE REGION WEDNESDAY NIGHT FOLLOWED BY HIGH PRESSURE AND FAIR WEATHER THROUGH FRIDAY. && .NEAR TERM /THROUGH TONIGHT/... SFC ANALYSIS SHOWS THE WARM FRONT OVER OHIO MOVING INTO FAR WESTERN PA AND STRETCHING ACROSS LAKE ERIE EARLY THIS MORNING. REGIONAL RADARS CONTINUE TO SHOW SHOWERS AND THUNDERSTORMS DEVELOPING ALONG THIS FRONTAL BOUNDARY. AS THIS WARM FRONT LIFTS NORTHWARD THROUGH THE LOWER LAKES EARLY THIS MORNING...THE COMBINATION OF AN INCREASING LLJ OVER WNY AND INSTABILITY ALOFT WILL LEAD TO SOME INCREASE IN SHOWER AND THUNDERSTORM COVERAGE ACROSS THE REGION. TODAY...AS SFC LOW PRESSURE CONTINUES TO LIFT TO THE NORTHEAST ACROSS THE CENTRAL GREAT LAKES INTO CANADA...A COLD FRONT WILL SLOWLY INCH TOWARDS WNY. WITH PWATS APPROACHING 2.00 INCHES AHEAD OF THE FRONT...AND MODEST INSTABILITY (BUFKIT SOUNDINGS SHOWING 500-1000 J/KG)WILL COMBINED WITH A STRENGTHEN LLJ TO PRODUCE SHOWERS AND THUNDERSTORMS ACROSS THE REGION. ADDITIONALLY...WITH PWATS NEAR 2.00 INCHES AND WITH SUCH A DEEP WARM LAYER (WBZ NEAR 12K)...THE ATMOSPHERE WILL BE PRIMED FOR HEAVY RAIN WITH ANY THUNDERSTORMS. A FEW OF THE STRONGER STORMS MAY PRODUCE SOME GUSTY WINDS...UP TO 50 KNOTS OR VERY SMALL HAIL. LATEST GUIDANCE SUGGESTING ANY FLASH FLOOD POTENTIAL WILL REQUIRE 2 TO 3 INCHES OF RAIN IN A VERY SHORT PERIOD OF TIME. AT THIS POINT...IT'S NOT LIKELY THAT THIS MUCH RAIN WILL FALL AS THESE STORMS WILL MOVE AT 25-30 KNOTS. HIGH ACROSS WESTERN AND NORTH CENTRAL NY WILL GENERALLY RANGE FROM THE LOW TO MID 80S...IT WILL AGAIN FEEL VERY MUGGY WITH DWPTS IN THE MID AND UPPER 60S. TONIGHT...MORE SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE AS THE COLD FRONT EVER SO SLOWLY MOVES INTO WESTERN AND NORTH CENTRAL NY THROUGH WEDNESDAY. EXPECT LOWS TO BOTTOM OUT IN THE MID TO UPPER 60S OVERNIGHT. && .SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/... IT WILL STILL BE QUITE UNSETTLED AS WE OPEN THIS PERIOD...BUT AS WE PROGRESS THROUGH THE LATTER PORTION OF THE WEEK...ANOTHER STRETCH OF FAIR DRY WEATHER CAN BE ANTICIPATED. STARTING WITH A BROAD VIEW OF THE SYNOPTIC PATTERN...A LOW AMPLITUDE FLOW WILL BE IN PLACE ACROSS THE COUNTRY DURING MUCH OF THIS TIME FRAME. THIS WILL KEEP US FROM EXPERIENCING ANOMALOUSLY HIGH MERCURY READINGS...BUT BUILDING HEIGHTS ACROSS THE EASTERN HALF OF THE NATION WILL POINT TOWARDS A BIG WARM UP...PARTICULARLY OUTSIDE OF THE SCOPE OF THIS PERIOD DURING THE UPCOMING WEEKEND. MORE ON THIS IN THE LONG TERM SECTION BELOW. WHILE THE TEMPERATURE TREND WILL BE EASY TO DECIPHER...IT WILL BE MUCH MORE CHALLENGING TO NAIL DOWN THE UNSETTLED WEATHER THAT WILL DOMINATE THE EARLY PORTION OF THIS FORECAST PERIOD. A WAVY COLD FRONTAL BOUNDARY WILL SLOWLY SETTLE ACROSS OUR FORECAST AREA ON WEDNESDAY. THE VARIOUS GUIDANCE PACKAGES DIFFER ON THE PLACEMENT AND TIMING OF THE LAST IN A SERIES OF WAVES THAT WILL WORK ITS WAY ALONG THIS FRONT...AND THIS IS IMPORTANT AS THIS FEATURE WILL ULTIMATELY DETERMINE IF OUR REGION WILL PICK UP A BENEFICIAL (AGRICULTURAL) SOAKING RAIN VERSUS MORE SIGNIFICANT WEATHER THAT COULD INCLUDE A CHANCE FOR LOCALIZED CONVECTIVE BASED FLOODING. IT IS WORTH NOTING THAT THE AREA HAS NOT PICKED UP SIGNIFICANT WIDESPREAD RAINS IN NEARLY TWO WEEKS...AND THAT HAS ALLOWED AREA TRIBUTARIES TO LOWER TO MID SUMMER LEVELS. WHILE PWAT VALUES WILL BE IN THE VCNTY OF 1.75 TO 2 INCHES...A PEEK AT THE FFG FROM THE RIVER FORECAST CENTERS SUGGEST THAT WE WOULD NEED AT LEAST 2.5 INCHES OF RAIN IN 3 HOURS OR MORE THAN 3 INCHES IN 6 HOURS TO PRODUCE ANY FLOODING. LESS RAIN WOULD BE NEEDED IN METRO AREAS AND IN REGIONS OF SIGNIFICANT TOPOGRAPHIC RELIEF. THIS BEING SAID...WILL RAISE POPS FROM LIKELY TO CATEGORICAL ACROSS MUCH OF THE REGION FOR WEDNESDAY AS THE SLOWLY MOVING FRONTAL BOUNDARY WILL BE ACCOMPANIED BY SOME STRONG UPPER LEVEL FORCING UNDER THE RIGHT REAR ENTRANCE REGION OF A 100KT H25 JET. WHILE BASIN AVERAGE RAINFALL SHOULD BE IN THE VCNTY OF A QUARTER TO A HALF INCH...THERE WILL BE THE RISK FOR SUBSTANTIALLY HIGHER AMOUNTS. THIS WOULD COME AS A RESULT OF HIGH PWAT VALUES...VERY SHORT MBE VECTORS WITHIN A LIGHT ENVIRONMENTAL WIND FIELD...AND A HEIGHTENED CHANCE FOR WARM RAIN PROCESSES. TO ADDRESS THE LATTER...A WEALTH OF CLOUD COVER WILL SEVERELY LIMIT DIURNAL INSTABILITY...WITH THIN CAPE PROFILES AND WARM LAYER CONVECTIVE CLOUD DEPTH OF 12-16K FT LENDING TOWARDS A FAVORABLE ENVIRONMENT FOR WARM RAIN PROCESSES. THIS WILL ESPECIALLY BE THE CASE OVER THE SOUTHERN TIER AND FINGER LAKES REGION. WILL INSERT SOME ENHANCED WORDING INTO THE GRIDS TO COVER THIS LOCALIZED HEAVY RAIN THREAT WHILE CONTINUING TO HIGHLIGHT IN THE HWO PRODUCT. USING A CONSENSUS FORECAST RELYING MAINLY ON THE ECMWF...A FRONTAL WAVE OVER PENNSYLVANIA WEDNESDAY EVENING WILL MAKE ITS WAY TO THE NEW ENGLAND COAST BY THURSDAY MORNING. WHILE THE SUPPORTING DYNAMICS FOR WIDESPREAD PCPN WILL EXIT THE BULK OF THE REGION...THERE WILL STILL BE A WEALTH OF LOW LEVEL MOISTURE IN PLACE WITHIN THE RESIDUAL CYCLONIC FLOW. WILL TAPER OFF THE SHOWERS DURING THE COURSE OF THE NIGHT WHILE BASICALLY HOLDING THE CLOUD COVER IN PLACE. ON THURSDAY...HIGH PRESSURE OVER CENTRAL ONTARIO WILL GRADUALLY BUILD ACROSS THE LOWER GREAT LAKES. THIS WILL PRODUCE A LIGHT NORTHERLY UPSLOPE FLOW ACROSS WESTERN NEW YORK...LIFTING THE REMAINING LOW LEVEL MOISTURE. MID LEVEL DRYING SHOULD HELP TO KEEP THE CLOUDS FROM PRODUCING MUCH IN THE WAY OF PCPN...BUT A SHOWER OR TWO CANNOT BE RULED OUT FOR THE FINGER LAKES AND INTERIOR SOUTHERN TIER. IT WILL FEEL A LITTLE MORE COMFORTABLE THOUGH AS DEW POINTS ARE FORECAST TO LOWER BACK INTO THE 50S TO NEAR 60 (VERSUS THE UPPER 60S). THE SFC HIGH WILL BUILD ACROSS OUR REGION THURSDAY NIGHT. WHILE THIS WILL ASSURE US OF FAIR WEATHER...THERE IS STILL SOME QUESTION AS TO HOW MUCH RESIDUAL LOW LEVEL MOISTURE WILL BE IN PLACE GIVEN THE OVERALL LIGHT FLOW. TEMPERATURES SHOULD LOWER INTO THE 50S REGIONWIDE FOR THE OVERNIGHT...MAKING THIS A MUCH MORE COMFORTABLE NIGHT THAN THE PREVIOUS THREE. HIGH PRESSURE OVER OUR REGION FRIDAY AND FRIDAY NIGHT WILL BE ACCOMPANIED BY BUILDING HGTS ACROSS ALL OF THE GREAT LAKES. THIS WILL TRANSLATE INTO FINE WEATHER FOR THE REGION WITH CLR/PC SKIES AND SEASONABLE TEMPERATURES. && .LONG TERM /SATURDAY THROUGH MONDAY/... A DECISIVE TURN TO MID SUMMER WEATHER DURING THIS PERIOD. UPPER LEVEL RIDGING WILL BE PARKED ACROSS THE EASTERN PORTION OF THE COUNTRY THROUGHOUT THIS PERIOD...AND AT THIS TIME OF YEAR...THAT CAN ONLY MEAN ONE THING. VERY WARM WEATHER. H85 TEMPS THAT WILL BE IN THE VCNTY OF 16C AT THE START OF THE WEEKEND ARE FORECAST TO CLIMB TO NEAR 20C BY EARLY NEXT WEEK. THIS WILL EASILY SUPPORT AFTERNOON TEMPERATURES IN THE 80S FOR SATURDAY AND SUNDAY...WITH READINGS TOPPING OUT BETWEEN 85 AND 90 FOR MONDAY (PENDING CLOUD COVER). THE HEAT WILL INITIALLY BE A 'DRY' HEAT WITH DEW POINTS AROUND 60...BUT AS SFC HIGH PRESSURE SLIDES OFF THE COAST...A SWATH OF SUB TROPICAL MOISTURE EXTENDING FROM THE GULF TO THE OHIO VALLEY AND UPPER MID WEST WILL SHIFT EAST...TAKING AIM ON OUR REGION FOR MONDAY. WHILE THERE WILL BE AN INCREASING CHANCE FOR DIURNALLY DRIVEN CONVECTION AS WE WORK FROM THE SECOND HALF OF THE WEEKEND INTO MONDAY...THE VAST MAJORITY OF THIS TIME PERIOD WILL BE RAIN FREE. && .AVIATION /09Z TUESDAY THROUGH SATURDAY/... AT 09Z...REGIONAL RADARS SHOW A FEW SHOWERS AND THUNDERSTORMS MOVING EAST AND NORTHEAST ACROSS LAKE ERIE INTO WNY...AND ACROSS THE NORTH COUNTRY. THESE SHOWERS AND THUNDERSTORMS ARE ASSOCIATED WITH THE WARM FRONT AND MAY BRIEFLY BRING REDUCED CIGS/VSBYS TO A FEW OF THE AIRFIELDS. ALTHOUGH...IT IS LIKELY THAT MOST AIRFIELDS WILL SEE CONTINUED VFR. TODAY...WITH DAYTIME HEATING SHOWERS AND THUNDERSTORMS WILL LIKELY INCREASE IN NUMBERS AND ANY STORM COULD BRING LOCALIZED IFR VSBYS IN A DOWNPOUR AND GUSTY WINDS WILL BE POSSIBLE. OUTLOOK... TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...MVFR FLIGHT CONDITIONS IN SHOWERS AND THUNDERSTORMS. THURSDAY THROUGH SATURDAY...NO SIGNIFICANT WEATHER EXPECTED. && .MARINE... WHILE THE PAST SEVERAL DAYS HAVE BEEN FAVORABLE FOR RECREATIONAL BOATING ACROSS THE LOWER GREAT LAKES...IT WILL BE UNSETTLED DURING THE NEXT 36 HOURS AS THEIR WILL BE THE RISK OF THUNDERSTORMS. MARINERS SHOULD THUS BE ALERT FOR SPECIAL MARINE WARNINGS THROUGH WEDNESDAY. OTHERWISE...MODERATE SOUTHERLIES WILL BE FOUND ACROSS THE LOWER GREAT LAKES TODAY WITH THE OFFSHORE FLOW PUSHING THE HIGHEST WAVES INTO CANADIAN WATERS. AS A COLD FRONT APPROACHES TONIGHT...WINDS WILL VEER TO THE SOUTHWEST WHILE WAVES WILL REMAIN BELOW SMALL CRAFT CRITERIA. THE FRONTAL BOUNDARY WILL STALL JUST TO THE SOUTH OF LAKES ERIE AND ONTARIO ON WEDNESDAY...SO UNSETTLED CONDITIONS WILL LIKELY REMAIN IN PLACE ALTHOUGH WINDS WILL GENERALLY BE LIGHT. FAIR WEATHER WILL RETURN TO THE LOWER GREAT LAKES FOR THURSDAY AND FRIDAY. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...AR NEAR TERM...AR SHORT TERM...RSH LONG TERM...RSH AVIATION...AR MARINE...RSH  FXUS61 KBUF 260809 AFDBUF AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BUFFALO NY 409 AM EDT TUE MAY 26 2015 .SYNOPSIS... PERSISTENT HIGH PRESSURE ANCHORED OFF THE EAST COAST WILL KEEP MID SUMMERLIKE WARMTH ACROSS WESTERN AND NORTH CENTRAL NEW YORK... WHILE INCREASING HUMIDITY AND SEVERAL DISTURBANCES WILL PROVIDE INCREASING CHANCES OF SOME MUCH NEEDED RAINFALL THROUGH MID WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 08Z...REGIONAL RADARS SHOW THE LAST OF THE SHOWERS ASSOCIATED WITH A DEPARTING SHORTWAVE/ATTENDANT LOW LEVEL JET NOW PUSHING ACROSS THE NORTH COUNTRY. WHILE THESE ARE GENERALLY LIGHT TO MODEST IN NATURE... THESE WILL PROBABLY STILL BE ABLE TO WET THE GROUND IN SPOTS BEFORE DEPARTING OUR AREA BY SHORTLY AFTER SUNRISE. ELSEWHERE...THE REST OF THE REGION REMAINS SITUATED IN BETWEEN SHORTWAVES AND DRY AS OF THIS WRITING. ONCE THE LEFTOVER SHOWERS EXIT THE NORTH COUNTRY...EXPECT LARGELY DRY AND QUIET WEATHER TO BE THE GENERAL RULE THROUGH THE MID TO LATE MORNING HOURS. AFTER THAT TIME...THE COMBINATION OF INCREASING DIURNAL INSTABILITY AND THE APPROACH OF YET ANOTHER MID LEVEL SHORTWAVE AND ATTENDANT MOISTURE FROM THE OHIO VALLEY SHOULD LEAD TO AN INCREASING POTENTIAL FOR CONVECTION THROUGH THE AFTERNOON HOURS. AT THIS POINT IT STILL APPEARS AS IF THE CONVECTION WILL BE MOST LIKELY TO INITIATE ALONG A DEVELOPING LAKE BREEZE BOUNDARY TO THE LEE OF LAKE ERIE AS WELL AS IN AREAS OF FAVORABLE OROGRAPHIC INFLUENCES...BEFORE SPREADING NORTHEASTWARD INTO THE GENESEE VALLEY AND FINGER LAKES AS ADDITIONAL LIFT FROM THE AFOREMENTIONED SHORTWAVE COMES INTO PLAY. WITH CAPE VALUES LARGELY APPEARING MODEST... CAPE PROFILES TALL/SKINNY IN NATURE...AND 0-6 KM BULK SHEAR VALUES GENERALLY LESS THAN 30 KNOTS...ANY POTENTIAL FOR SEVERE STORMS STILL APPEARS TO BE FAIRLY LIMITED. AS WE GET INTO THIS EVENING...LINGERING DIURNALLY-DRIVEN CONVECTION SHOULD CONTINUE TO LIFT NORTHEASTWARD WHILE WEAKENING OWING TO THE LOSS OF HEATING AND THE DEPARTURE OF THE SUPPORTING SHORTWAVE. THIS SHOULD LEAD TO A RELATIVE MINIMUM IN CONVECTION FOR THE MIDDLE PART OF THE NIGHT...BEFORE AN APPROACHING MID LEVEL TROUGH AND ATTENDANT LEAD SHORTWAVE/PRE-FRONTAL TROUGH BRINGS AN INCREASING THREAT FOR SHOWERS AND STORMS BACK INTO FAR WESTERN NEW YORK LATE. WITH RESPECT TO TEMPERATURES...850 MB TEMPS OF +14C TO +15C SHOULD TRANSLATE INTO WIDESPREAD SURFACE HIGHS IN THE UPPER 70S TO MID 80S TODAY...WITH ANY REAL LAKE COOLING LIKELY CONFINED TO AREAS IMMEDIATELY NORTHEAST OF THE LAKES. WITH AN EVEN MORE HUMID AIRMASS AND A CONTINUED SOUTHERLY/SOUTHWESTERLY LOW LEVEL FLOW IN PLACE... LOWS TONIGHT WILL LIKELY NOT FALL BELOW THE MID TO UPPER 60S. && .SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/... WHILE WE WILL LIKELY PICK UP SOME BADLY NEEDED RAINFALL ON WEDNESDAY...THE BULK OF THE DAY COULD PROVE TO BE PCPN FREE. AS WAS THE CASE IN THE PRECEDING 48 HOURS...STRONG RIDGING FOUND JUST OFF THE EAST COAST WILL CONTINUE TO CIRCULATE WARM AND VERY HUMID AIR NORTHWARD ACROSS THE LOWER GREAT LAKES...AS A WIDE OPEN GULF WILL SUPPLY PWAT VALUES OF 1.75"...AT LEAST FOR THE FIRST HALF OF THE DAY. THE RESULTING UNSTABLE AIRMASS WILL BE VERY SUPPORTIVE OF CONVECTION...BUT THE DIFFICULT PART WILL BE TRYING TO TIME THE VARIOUS SHORTWAVES AND BOUNDARIES THAT WILL TRIGGER SUCH. A SHORTWAVE FOUND OVER THE OHIO VALLEY TUESDAY EVENING WILL PUSH NORTHEAST AROUND THE PERIPHERY OF THE AFOREMENTIONED EAST COAST RIDGE AND CROSS OUR FORECAST AREA DURING THE FIRST HALF OF WEDNESDAY. THIS WILL LIKELY PRODUCE A ROUND OF SHOWERS AND THUNDERSTORMS DURING THE MORNING HOURS. THE GOOD NEWS IS THAT THE DIURNAL TIMING OF THIS CONVECTION WILL BE SUCH THAT INSTABILITY WILL BE SOMEWHAT LIMITED (<500 J/KG)...THUS MINIMIZING THE RISK FOR ANY SEVERE WEATHER. ON THE OTHER HAND THOUGH...THE MOISTURE RICH AIRMASS WILL BE RIPE FOR HEAVY RAIN WITH SHORT MBE VECTORS SUGGESTING THE POTENTIAL FOR SLOW MOVING DOWNPOURS. THE THREAT FOR HEAVY RAIN WILL ALSO BE ENHANCED BY WARM CLOUD DEPTHS THAT ARE FORECAST TO OVER 10K FT/3 KM DEEP...AND THE LOWER CAPE VALUES QUOTED ABOVE. LOW TO MODERATE AMOUNTS OF CAPE ARE MORE FAVORABLE FOR HEAVY RAIN BECAUSE WARM RAIN PROCESSES REQUIRE TIME TO CONVERT CONDENSATE TO RAIN DROPS. HIGH CAPE ENVIRONMENTS TEND TO ACCELERATE WATER VAPOR THROUGH THE WARM CLOUD LAYER...LIMITING RAINFALL PRODUCTION. IN ANY CASE...WEDNESDAY MORNING WILL LIKELY BE UNSETTLED ACROSS WESTERN AND NORTH CENTRAL NEW YORK SO WILL INCREASE POPS TO LIKELY FOR THE MORNING HOURS AND ALSO MENTION HEAVY RAIN. SUBSIDENCE AND MARGINAL MID LEVEL DRYING IN THE WAKE OF THE SHORTWAVE SHOULD THEN LEAD TO SOME CLEARING...AT LEAST OVER THE WESTERN COUNTIES DURING THE AFTERNOON. WILL THUS BACK OFF ON THE AFTERNOON POPS FROM CONTINUITY...ESPECIALLY OVER THE WESTERN COUNTIES. ANY CLEARING WILL LEAD TO THE BUILD UP OF MORE INSTABILITY WHICH COULD 'SET THE TABLE' FOR ANOTHER ROUND OF CONVECTION WITH AN APPROACHING COOL FRONT. THIS COOL FRONT WILL CROSS OUR FORECAST AREA DURING THE FIRST HALF OF WEDNESDAY NIGHT. WHILE THE DEEPEST PLUME OF MOISTURE WILL BE WELL TO OUR EAST (OVR NEW ENGLAND)...PWAT VALUES IN EXCESS OF AN INCH WILL BE IN PLACE ALONG WITH SBCAPES OF 500-1000 J/KG. WHILE IT WOULD NOT BE OUT OF THE QUESTION THAT THESE STORMS COULD PRODUCE STRONG WIND GUSTS...THE 0-3KM SHEAR VALUES ARE ONLY FORECAST TO BE IN THE VCNTY OF 30 M/S AHEAD OF AND ALONG THE FRONT...SO AM NOT OVERLY IMPRESSED AT THIS POINT. CONVECTION ASSOCIATED WITH THIS FRONTAL PASSAGE WILL DIE DOWN AFTER MIDNIGHT. ON THURSDAY...HIGH PRESSURE CENTERED NEAR JAMES BAY WILL NOSE SOUTH ACROSS THE LOWER GREAT LAKES. THIS WILL BRING US A BRIEF REPRIEVE FROM THE HUMID...UNSETTLED WEATHER AS DEW POINTS WILL TEMPORARILY DROP BACK INTO THE 50S. THE DRIER AIRMASS SHOULD ALLOW FOR A FAIR AMOUNT OF SUNSHINE...PARTICULARLY DURING THE AFTERNOON. IT WILL ONLY BE MARGINALLY COOLER THOUGH WITH MANY AREAS STILL CLIMBING INTO THE UPPER 70S. AFTER WHAT SHOULD PROVE TO BE A FAIRLY COMFORTABLE NIGHT THURSDAY NIGHT WHEN TEMPERATURES ARE EXPECTED TO DROP BACK TO BETWEEN 55 AND 60...IT WILL ONCE AGAIN BECOME WARM FOR FRIDAY. THE EAST COAST RIDGE WILL AMPLIFY DURING THE DAY FRIDAY WITH A DEEPENING SOUTHERLY FLOW BECOMING RE-ESTABLISHED OVER THE LOWER GREAT LAKES IN ADVANCE OF THE NEXT COLD FRONTAL BOUNDARY. H85 TEMPS WILL CLIMB BACK INTO THE MID TEENS C...WHICH WILL SUPPORT AFTERNOON MAX TEMPS IN THE LOW TO MID 80S. THIS WARMING WILL COMBINE WITH AN INCREASINGLY UNSTABLE AIRMASS AND ANY LAKE BREEZE BOUNDARY TO FUEL POSSIBLE AFTERNOON AND EVENING THUNDERSTORMS ACROSS THE SOUTHERN TIER. ELSEWHERE...PARTLY SUNNY WARM AND HUMID CONDITIONS SHOULD PREVAIL. && .LONG TERM /SATURDAY THROUGH MONDAY/... THINGS SHOULD BECOME MUCH MORE ACTIVE THOUGH AS WE MOVE INTO THE WEEKEND. A POTENT UPPER LEVEL VORT MAX DROPPING OUT OF THE CANADIAN ARCTIC WILL CARVE OUT A TROUGH ACROSS THE CANADIAN PRAIRIE PROVINCES LATE THIS WEEK. THIS TROUGH IS FORECAST TO CROSS NORTHERN ONTARIO AND MOVE INTO EASTERN QUEBEC SATURDAY. THOUGH TIMING BETWEEN THE GLOBAL MODELS DIFFERS SLIGHTLY...THE GENERAL CONSENSUS IS FOR THE THIS FEATURE TO PUSH A STRONG COLD FRONT ACROSS THE FORECAST AREA LATE SATURDAY OR SATURDAY NIGHT. GIVEN STRONG SYNOPTIC FORCING ASSOCIATED WITH THE FRONT...EXPECT SOME SHOWERS/THUNDERSTORMS AS THE FRONT MOVES THROUGH. WHILE IT WILL REMAIN QUITE WARM AND MUGGY AHEAD OF SATURDAY'S FRONT... CONSIDERABLY COOLER AND DRIER WEATHER IS ANTICIPATED ON SUNDAY AS THE COLD FRONT WILL SETTLE TO OUR SOUTH...YIELDING PLENTY OF SUNSHINE AND HIGHS IN THE 60S. WARMING WILL ONCE AGAIN OVERSPREAD THE LOWER GREAT LAKES ON MONDAY AS THE RETURN FLOW AROUND HIGH PRESSURE OVER NEW ENGLAND WILL ENCOURAGE H85 TEMPS TO CLIMB BACK TOWARDS +10C. && .AVIATION /08Z TUESDAY THROUGH SATURDAY/... LINGERING SHOWERS ACROSS THE NORTH COUNTRY WILL CONTINUE TO DIMINISH EARLY THIS MORNING AS THEIR RESPONSIBLE SHORTWAVE/ATTENDANT 40-50 KNOT LOW LEVEL JET AND THE ZONE OF LOW LEVEL CONVERGENCE ON ITS FRONT FLANK SLIDES EASTWARD AND OUT OF OUR AREA. ELSEWHERE...THE REMAINDER OF THE REGION WILL BE IN BETWEEN SHORTWAVES AND SHOULD THUS REMAIN LARGELY DRY. EXPECT VFR CONDITIONS TO LARGELY CONTINUE TO PREVAIL...WITH THE POSSIBLE EXCEPTION OF NEAR KART WHERE THERE STILL IS A CHANCE SOME LOWER CLOUDS AND FOG COULD DEVELOP. DURING THE DAY TODAY...MAINLY DRY/GENERAL VFR CONDITIONS SHOULD PERSIST INTO THE MID TO LATE MORNING HOURS...BEFORE INCREASING DIURNAL INSTABILITY AND THE APPROACH OF A MID LEVEL SHORTWAVE LEADS TO THE DEVELOPMENT OF SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS THIS AFTERNOON. WHILE THESE SHOULD PRIMARILY BE FOCUSED FROM THE LEE OF LAKE ERIE NORTHEASTWARD ACROSS THE GENESEE VALLEY AND FINGER LAKES...THESE COULD BRING LOCALIZED REDUCTIONS TO MVFR AT JUST ABOUT ANY LOCATION... SAVE FOR NORTHERN PORTIONS OF THE NORTH COUNTRY AND SAINT LAWRENCE VALLEY. AS WE GET INTO THIS EVENING...LINGERING DIURNALLY-DRIVEN CONVECTION SHOULD CONTINUE TO LIFT NORTHEASTWARD WHILE WEAKENING OWING TO THE LOSS OF HEATING AND THE DEPARTURE OF THE SUPPORTING SHORTWAVE. THIS SHOULD LEAD TO A RELATIVE MINIMUM IN CONVECTION FOR THE MIDDLE PART OF THE NIGHT...BEFORE AN APPROACHING MID LEVEL TROUGH AND ATTENDANT LEAD SHORTWAVE/PRE-FRONTAL TROUGH BRINGS AN INCREASING THREAT FOR SHOWERS AND STORMS BACK INTO FAR WESTERN NEW YORK LATE. AT THIS POINT EXPECT THAT VFR CONDITIONS WILL CONTINUE TO LARGELY PREVAIL.. THOUGH LOCAL REDUCTIONS TO MVFR WILL REMAIN POSSIBLE WITHIN ANY CONVECTION. OUTLOOK... WEDNESDAY...VFR/MVFR WITH SHOWERS LIKELY ALONG WITH A CHANCE OF THUNDERSTORMS. WEDNESDAY NIGHT...MAINLY VFR WITH SCATTERED SHOWERS AND THUNDERSTORMS/ATTENDANT MVFR. THURSDAY...MAINLY VFR WITH A LOW CHANCE OF EARLY MORNING SHOWERS ACROSS THE NORTH COUNTRY. FRIDAY...MAINLY VFR WITH A CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS THE SOUTHERN TIER AND INTERIOR PORTIONS OF THE FINGER LAKES. SATURDAY...MAINLY VFR WITH SCATTERED SHOWERS AND THUNDERSTORMS. && .MARINE... HIGH PRESSURE ANCHORED OFF THE EAST COAST WILL KEEP A WEAK TO MODEST PRESSURE GRADIENT INTACT ACROSS THE LOWER GREAT LAKES THROUGH THE END OF THE WEEK. AS A RESULT...LIGHT TO MODEST WINDS AND NEGLIGIBLE WAVES WILL CONTINUE TO BE THE GENERAL RULE...THOUGH ANY THUNDERSTORMS COULD STILL PRODUCE LOCALLY HIGHER WINDS AND WAVES THROUGH MIDWEEK. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...JJR NEAR TERM...JJR SHORT TERM...RSH LONG TERM...RSH/WOOD AVIATION...JJR MARINE...JJR  FXUS61 KBUF 100536 AFDBUF AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BUFFALO NY 136 AM EDT FRI JUL 10 2015 .SYNOPSIS... HIGH PRESSURE BUILDING INTO THE REGION WILL BRING CLEARING SKIES TONIGHT AND SUNNY SKIES FOR FRIDAY. HIGH PRESSURE WILL THEN REMAIN IN CONTROL THROUGH THE WEEKEND WITH TEMPERATURES WARMING BACK TO MID SUMMER HEAT. && .NEAR TERM /THROUGH TODAY/... HIGH PRESSURE IS SLOWLY BUILDING INTO THE OHIO VALLEY OVERNIGHT...BUT ONLY A MODEST PUSH OF LOW LEVEL DRY AIR HAS HUNG UP ACROSS SOUTHERN ONTARIO WITH LITTLE CHANGE IN AIRMASS SOUTH OF THE BORDER. THIS WILL ALLOW THE AMPLE LOW LEVEL MOISTURE TO PRODUCE AREAS OF FOG OVERNIGHT AS A STRONG NEAR SURFACE INVERSION DEVELOPS WITH RADIATIONAL COOLING. ONCE THE FOG BURNS OFF IN THE MORNING...MOSTLY SUNNY SKIES ARE EXPECTED FRIDAY ALONG WITH LOWER DEWPOINTS. AS THE HIGH PRESSURE IS OF MID CONTINENTAL ORIGIN...THE HIGH TEMPERATURES ON FRIDAY WILL BE IN THE MID TO UPPER 70S. && .SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/... A SUBTROPICAL RIDGE CENTERED OVER TEXAS THIS WEEKEND WILL NOSE NORTHWARDS ACROSS THE GREAT LAKES REGION...AND THIS WILL GUARANTEE FAIR DRY WEATHER ACROSS THE BULK OF FOR OUR FORECAST AREA THROUGH AT LEAST SUNDAY EVENING. THE RAIN FREE WEATHER WILL BE ACCOMPANIED BY MID SUMMER WARMTH AND MODERATELY HIGH HUMIDITY LEVELS. THE PERIOD WILL OPEN FRIDAY NIGHT WITH HIGH PRESSURE CENTERED OVER LAKE ERIE. A WEALTH OF DRY AIR OVER THE LOWER GREAT LAKES WILL TEAM UP WITH THE FAIR WEATHER SYSTEM TO PRODUCE STARLIT SKIES AND COMFORTABLE SLEEPING CONDITIONS ACROSS OUR REGION. MID LEVEL RIDGING WILL THEN PUSH EAST ACROSS THE LOWER GREAT LAKES ON SATURDAY WHILE THE CORRESPONDING SFC HIGH WILL REMAIN OVER OUR REGION. THIS WILL KEEP FAIR DRY WEATHER IN PLACE...AND WITH H85 TEMPS CLIMBING TO NEAR 16C...AFTERNOON HIGHS WILL CLIMB INTO THE UPPER 70S ACROSS THE HIGHEST TERRAIN TO THE MID 80S ACROSS THE GENESEE VALLEY AND THE LAKE PLAINS SOUTH OF LAKE ONTARIO. AS THE CREST OF THE PROGRESSIVE MID LEVEL RIDGE PASSES ACROSS THE LOWER GREAT LAKES ON SUNDAY...A DEEPER SOUTHERLY FLOW WILL BECOME ESTABLISHED OVER OUR REGION. THIS WILL ALLOW H85 TEMPS TO CLIMB TO NEAR 18C WHILE ALSO ADVECTING HIGHER DEW POINT AIR ACROSS THE FORECAST AREA. THIS WILL PUSH HIGH TEMPERATURES FOR ALL AREAS INTO THE 80S...WITH MID/UPPER 80S ACROSS THE LOWER GENESEE VALLEY AND SOUTH LAKE PLAIN OF LAKE ONTARIO. OUR AIRMASS WILL BECOME INCREASINGLY UNSTABLE AS A RESULT...WITH A SLIGHT CHC FOR AFTERNOON SHOWERS OR THUNDERSTORMS. THE POTENTIAL FOR CONVECTION WILL FURTHER INCREASE SUNDAY NIGHT WHEN A SHORTWAVE WILL APPROACH OUR REGION FROM THE UPPER GREAT LAKES. && .LONG TERM /MONDAY THROUGH THURSDAY/... AFTER SEVERAL DAYS OF FINE WEATHER...THIS PERIOD WILL BE NOTABLY MORE UNSETTLED. UNUSUALLY STRONG RIDGING EXTENDING NORTH FROM THE TEXAS PANHANDLE WILL ENCOURAGE EQUALLY ANOMALOUS TROUGHING OVER THE EASTERN THIRD OF NORTH AMERICA. SEVERAL PACIFIC SHORTWAVES DIGGING INTO THE AMPLIFYING TROUGH WILL GENERATE FREQUENT SHOWERS ACROSS OUR REGION FOR AT LEAST THE EARLY PORTION OF THE WEEK...BUT GUIDANCE PACKAGES HAVE BEEN ANYTHING BUT CONSISTENT WITH THE DETAILS. && .AVIATION /06Z FRIDAY THROUGH TUESDAY/... THE MAIN CONCERN THROUGH EARLY FRIDAY WILL BE FOG COVERAGE. THE FOG HAS BEEN PATCHY SO FAR WITH MOST OF THE MORE WIDESPREAD FOG LIMITED TO THE SOUTHERN TIER AND ALSO THE NORTH COUNTRY WHERE VSBY WILL CONTINUE TO BE IFR AND NEAR AIRFIELD MINIMUMS THROUGH THE REST OF THE NIGHT. ELSEWHERE EXPECT FOG TO EXPAND ACROSS WESTERN NY FOR A FEW HOURS JUST BEFORE DAYBREAK WITH IFR PROBABLE AT KBUF-KROC-KIAG 08Z-12Z. THE FOG WILL BURN OFF BY MID MORNING AND LEAVE VFR TO PREVAIL THE REST OF FRIDAY AS HIGH PRESSURE BUILDS SLOWLY EAST THROUGH THE OHIO VALLEY. EXPECT A FEW SCT DIURNAL CUMULUS INLAND FROM THE LAKES AND SOME PATCHY THIN CIRRUS THROUGH THE DAY. OUTLOOK... SATURDAY AND SUNDAY...VFR. MONDAY AND TUESDAY...MAINLY VFR WITH A CHANCE OF SHOWERS AND THUNDERSTORMS AND ASSOCIATED BRIEF MVFR/IFR. && .MARINE... LOW PRESSURE WILL MOVE ACROSS NORTHERN PENNSYLVANIA WITH NORTHEAST 10-15 KNOTS ON THE LOWER LAKES ON THE NORTHERN PERIPHERY OF THE LOW. HIGH PRESSURE WILL THEN BUILD INTO THE REGION FRIDAY AND REMAIN IN CONTROL THROUGH THE WEEKEND WITH RELATIVELY LIGHT WINDS AND FLAT WAVE ACTION. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...TMA/WCH NEAR TERM...HITCHCOCK/TMA/WCH SHORT TERM...RSH LONG TERM...RSH AVIATION...HITCHCOCK MARINE...WCH  FXUS61 KBUF 040237 AFDBUF AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BUFFALO NY 1037 PM EDT MON AUG 3 2015 .SYNOPSIS... A COLD FRONT WILL DROP SOUTHWARD ACROSS THE REGION OVERNIGHT...FOLLOWED BY A SECONDARY COLD FRONT ON TUESDAY AND TUESDAY NIGHT. THIS WILL BRING A CHANCE OF SHOWERS AND POSSIBLY A THUNDERSTORM. OTHERWISE IT WILL BECOME COOLER WITH BELOW NORMAL TEMPERATURES FOR REMAINDER OF THE WEEK. && .NEAR TERM /THROUGH TUESDAY/... A VORT MAX WILL PIVOT AROUND AN UPPER LEVEL TROUGH LOCATED IN CENTRAL CANADA. THIS WILL PUSH A SERIES OF COLD FRONTS ACROSS OUR REGION THROUGH TUESDAY. THE INITIAL COLD FRONT IS IN THE PROCESS OF CROSSING OUR REGION EARLY THIS EVENING...WITH THE BOUNDARY EXPECTED TO CONTINUE TO DROP SOUTHWARD ACROSS THE CWA OVERNIGHT. THIS MAY SPARK SOME SPARSE SHOWERS OVERNIGHT...BUT RADAR/MODEL TRENDS SUPPORT A MAINLY DRY OVERNIGHT PERIOD. A PARTIAL CLEARING MAY ALLOW PATCHY FOG TO DEVELOP...ESPECIALLY IN THE VALLEYS OF THE SOUTHERN TIER. TEMPERATURES WILL BE COOLER TONIGHT WITH LOWS RANGING FROM THE MID-50S TO LOWER 60S. A MORE SUBTLE SECONDARY BOUNDARY WILL GRADUALLY PUSH INTO THE REGION ON TUESDAY. THIS COMBINED WITH THE UPPER LEVEL TROUGH SHOULD BE ENOUGH FOR SOME SHOWERS AND POSSIBLY THUNDERSTORMS TO DEVELOP. 00Z NAM AND THE LATEST HRRR GUIDANCE SUGGEST THE MOST WIDESPREAD SHOWERS WILL BE EAST OF LAKE ONTARIO AS A SUBTLE WAVE CROSSES WITH THE FRONT. THIS WAVE WILL EXIT...BUT AS THE FRONT SAGS SOUTH AND WITH DAYTIME HEATING EXPECT ANOTHER BATCH OF STEADIER SHOWERS TO DEVELOP SOUTH OF LAKE ONTARIO ALONG THE SURFACE CONVERGENCE BOUNDARY. THIS SAID...WITH A CYCLONIC FLOW ALOFT DUE TO THE UPPER LEVEL TROUGH...IT IS DIFFICULT TO RULE OUT AT LEAST A CHANCE FOR SHOWERS AT ANY LOCATION. HIGHS WILL BE NOTABLY COOLER...ONLY IN THE LOWER TO MID 70S IN MOST AREAS. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/... EVENING UPDATE...A LOBE OF UNSEASONABLY COOL -1SD TO -2SD 850MB AIR WILL SWING ACROSS THE EASTERN GREAT LAKES TUESDAY NIGHT AND WEDNESDAY. THIS WILL INCREASE LAKE INDUCED INSTABILITY LEVELS OVER LAKES ERIE AND ONTARIO WITH THE POTENTIAL FOR LAKE ENHANCED RAIN SHOWERS EMBEDDED WITHIN MORE WIDESPREAD CHANCES OF SHOWERS AHEAD OF A 500MB VORT MAX. PREVIOUS DISCUSSION...THE LONGWAVE TROUGH AXIS WILL BE CENTERED ACROSS THE LOWER GREAT LAKES AS WE MOVE INTO THE MIDWEEK...RESULTING IN A COOL AND UNSETTLED START TO THE PERIOD. THE COMBINATION OF DPVA AND COLDER AIR ALOFT ASSOCIATED WITH THE TROUGH WILL MAKE TUESDAY NIGHT AND WEDNESDAY MORNING THE MOST UNSETTLED PART OF THE PERIOD. IN FACT...WITH 850MB TEMPS FALLING TO +8C TO +10C AND CYCLONIC WESTERLY FLOW IN PLACE ACROSS THE AREA...IT IS QUITE POSSIBLE THAT WE COULD SEE THE DEVELOPMENT OF LAKE EFFECT RAIN SHOWERS DOWNSTREAM OF LAKE ERIE...AND TO A GREATER EXTENT EAST OF OF LAKE ONTARIO WHERE LONGER FETCH SHOULD COMPENSATE FOR THE LACK OF DEEP MOISTURE. AS ELUDED TO ABOVE...AREAS DOWNWIND OF LAKE ERIE WILL BE ON THE SOUTHERN FRINGE OF THE DEEPER SYNOPTIC MOISTURE...HENCE THE LOWER POPS ACROSS WESTERN NY. HOWEVER IT IS WORTH NOTING THAT A STRONG VORT MAX IS PROGGED TO BE CROSSING THE FORECAST AREA OVERNIGHT...AND THIS WILL YIELD AT LEAST A CHANCE OF SHOWERS ELSEWHERE. NONETHELESS...EVEN WHERE WE DON'T SEE LAKE EFFECT SHOWERS...WE WILL LIKELY SEE AN ABUNDANCE OF CLOUD COVER. THE COOL AIR ASSOCIATED WITH THE TROUGH WILL YIELD LOWS IN THE 50S EXCEPT FOR IMMEDIATELY ALONG THE LAKE WHERE TEMPS WILL BOTTOM OUT AROUND 60. ANY LINGERING SHOWERS SHOULD TAPER OFF WEDNESDAY MORNING AS THE MAIN VORT MAX MOVES INTO EASTERN NEW YORK AND DIURNAL HEATING DISRUPTS ANY LINGERING LAKE EFFECT SHOWERS. HOWEVER WE MAY SEE A RESURGENCE OF SHOWER ACTIVITY EAST OF LAKE ONTARIO BY WEDNESDAY AFTERNOON AS THE CORE OF THE UPPER LEVEL TROUGH WILL STILL BE OVERHEAD THE NORTH COUNTRY AND EASTERN NEW YORK WITH A DECENT AMOUNT OF DIURNAL CLOUDINESS ELSEWHERE ACROSS THE FORECAST AREA ALONG WITH SEASONABLY COOL TEMPERATURES FEATURING HIGHS IN THE LOWER 70S. THE CORE OF THE COLD AIR ALOFT WILL MOVE ACROSS THE REGION WEDNESDAY NIGHT...CAUSING TEMPERATURES TO RUN A COUPLE OF DEGREES COOLER WITH LOWS IN THE LOW TO MID 50S EXCEPT IMMEDIATELY ALONG THE LAKESHORES WHERE LOWS RUN CLOSE TO THE 60 DEGREE MARK. UNLIKE TUESDAY NIGHT...LAKE EFFECT SHOWERS ARE NOT EXPECTED TO BE AN ISSUE OWING TO INCREASINGLY DRY AIR ALOFT AND NOMINALLY STRONGER SHEAR. HOWEVER...WE MAY SEE A FEW AREAS OF LAKE-INDUCED CLOUDINESS LINGER EAST OF LAKE ONTARIO AS THE BACK EDGE OF THE TROUGH MOVES THROUGH THE AREA. CONDITIONS WILL REMAIN DRY THURSDAY AND THURSDAY NIGHT AS THE UPPER LEVEL TROUGH GIVES WAY TO ZONAL FLOW ALOFT. THE QUESTION MARK IS A STORM SYSTEM PROGGED TO CROSS THE OHIO VALLEY AND CENTRAL APPALACHIANS THURSDAY AND THURSDAY NIGHT. THIS SYSTEM MAY BRING A FEW SHOWERS TO THE SOUTHERN TIER DEPENDING ON HOW FAR NORTH IT DRIFTS...HOWEVER FOR NOW WILL MAINTAIN LOW CHANCE POPS FOR THE TIME BEING. WITH NO SIGNIFICANT TEMPERATURE ADVECTION GOING ON...TEMPERATURES WILL RUN CLOSE TO WEDNESDAY/WEDNESDAY NIGHT'S READINGS WITH HIGHS IN THE LOWER 70S AND LOWS IN THE 50S. && .LONG TERM /FRIDAY THROUGH MONDAY/... THE LONGWAVE TROUGH WILL MAINTAIN ITS POSITION OVER EASTERN CANADA THROUGH THE WEEKEND AS A SERIES OF SHORTWAVES MOVING ALONG THE U.S. CANADIAN BORDER WILL LIKELY RE-AMPLIFY THE TROUGH ACROSS THE GREAT LAKES. WHILE THERE ARE CONSIDERABLE DIFFERENCES ON THE DETAILS IN THE EVOLUTION OF THIS SCENARIO...THIS GENERAL TREND SUGGESTS THAT WE WILL SEE AT LEAST A CHANCE OF SHOWERS THIS WEEKEND WITH TEMPERATURES THAT WILL CONTINUE TO RUN ON THE COOLER SIDE OF AVERAGE. && .AVIATION /03Z TUESDAY THROUGH SATURDAY/... EXPECT MAINLY VFR CONDITIONS LATE THIS EVENING AS THE FIRST OF TWO COLD FRONTS DROPS SOUTH OF THE REGION. AREAL COVERAGE OF SHOWERS SHOULD BE QUITE SPARSE WITH ONLY A SMALL CHANCE FOR BRIEF VSBY RESTRICTIONS. PERHAPS THE BIGGER CONCERN FOR AVIATION IS THE POTENTIAL FOR FOG TO DEVELOP TONIGHT. IT APPEARS THAT FOG WILL BE MOST WIDESPREAD ACROSS THE VALLEYS OF THE SOUTHERN TIER...WHICH MAY IMPACT JHW. FOG CANNOT COMPLETELY BE RULED OUT ELSEWHERE...BUT THE CHANCE IS SMALL. THE SECOND COLD FRONT WILL APPROACH THE AREA TUESDAY MORNING AND GRADUALLY ACROSS THE REGION THROUGH TUESDAY NIGHT. THIS WILL BRING AN INCREASE IN CLOUDS...AND SOME SHOWERS WHICH WILL BECOME MORE NUMEROUS DURING THE AFTERNOON HOURS. SHOWERS...AND POSSIBLY A THUNDERSTORM...MAY RESULT IN PERIODS OF MVFR OR LOWER CONDITIONS. OUTLOOK... TUESDAY NIGHT AND WEDNESDAY...MAINLY VFR. A CHANCE OF SHOWERS. WEDNESDAY NIGHT THROUGH MONDAY...VFR. && .MARINE... WINDS HAVE DIMINISHED WHICH HAS ALLOWED THE SMALL CRAFT ADVISORY TO BE DROPPED. A FALL LIKE AIRMASS IN THE WAKE OF THIS SECOND COLD FRONT COULD SET THE STAGE FOR WATERSPOUTS ON LAKE ONTARIO TUESDAY NIGHT AND WEDNESDAY. BUFKIT SOUNDINGS SHOW STEEP CONVECTIVE CLOUD DEPTHS AND LAKE-850 DELTA-TS OF AROUND 15C WHICH FIT THE SZILAGYI WATERSPOUT NOMOGRAM POTENTIAL FOR UPPER LOW WATERSPOUTS. A SLIGHT CHANCE HAS BEEN ADDED INTO THE FORECAST OVER THE LAKES. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...APFFEL NEAR TERM...APFFEL SHORT TERM...SMITH/WOOD LONG TERM...WOOD AVIATION...APFFEL MARINE...APFFEL/SMITH  FXUS61 KBUF 040615 AFDBUF AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BUFFALO NY 215 AM EDT TUE AUG 4 2015 .SYNOPSIS... SOMEWHAT UNSETTLED WEATHER WILL BE FOUND ACROSS THE REGION TUESDAY AND TUESDAY EVENING IN ADVANCE OF A SECONDARY COLD FRONT THAT WILL CROSS THE REGION TUESDAY NIGHT. FOLLOWING THE PASSAGE OF THIS SECOND COLD FRONT...SOME SCATTERED SHOWERS WILL LINGER ACROSS THE NORTH COUNTRY THROUGH WEDNESDAY...OTHERWISE IT WILL TURN DRIER AND COOLER FOR THE REMAINDER OF THE WORK WEEK. && .NEAR TERM /THROUGH TODAY/... FOR THE BALANCE OF THE NIGHT...OUR REGION SHOULD EXPERIENCE MAINLY DRY WEATHER SAVE FOR A FEW SHOWERS PASSING ACROSS LAKE ONTARIO AND INTO THE NORTH COUNTRY OUT AHEAD OF A WEAK SURFACE TROUGH... AND A LINGERING SHOWER OR TWO ACROSS INTERIOR PORTIONS OF THE SOUTHERN TIER. SOME PARTIAL CLEARING MAY ALSO ALLOW SOME PATCHY FOG TO DEVELOP...ESPECIALLY IN THE VALLEYS OF THE SOUTHERN TIER AND SOUTHEAST OF LAKE ONTARIO WHERE THE STEADIEST SHOWERS FELL ON MONDAY. OTHERWISE...TEMPERATURES WILL BE COOLER WITH OVERNIGHT LOWS RANGING FROM THE MID 50S TO LOWER 60S. A MORE SUBTLE SECONDARY BOUNDARY WILL GRADUALLY PUSH INTO THE REGION ON TUESDAY. THIS COMBINED WITH THE UPPER LEVEL TROUGH SHOULD BE ENOUGH FOR SOME SHOWERS AND POSSIBLY THUNDERSTORMS TO DEVELOP. 00Z NAM AND THE LATEST HRRR GUIDANCE SUGGEST THE MOST WIDESPREAD SHOWERS WILL BE EAST OF LAKE ONTARIO AS A SUBTLE WAVE CROSSES WITH THE FRONT. THIS WAVE WILL EXIT...BUT AS THE FRONT SAGS SOUTH AND WITH DAYTIME HEATING EXPECT ANOTHER BATCH OF STEADIER SHOWERS TO DEVELOP SOUTH OF LAKE ONTARIO ALONG THE SURFACE CONVERGENCE BOUNDARY. THIS SAID...WITH A CYCLONIC FLOW ALOFT DUE TO THE UPPER LEVEL TROUGH...IT IS DIFFICULT TO RULE OUT AT LEAST A CHANCE FOR SHOWERS AT ANY LOCATION. HIGHS WILL BE NOTABLY COOLER...ONLY IN THE LOWER TO MID 70S IN MOST AREAS. && .SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/... EVENING UPDATE...A LOBE OF UNSEASONABLY COOL -1SD TO -2SD 850MB AIR WILL SWING ACROSS THE EASTERN GREAT LAKES TUESDAY NIGHT AND WEDNESDAY. THIS WILL INCREASE LAKE INDUCED INSTABILITY LEVELS OVER LAKES ERIE AND ONTARIO WITH THE POTENTIAL FOR LAKE ENHANCED RAIN SHOWERS EMBEDDED WITHIN MORE WIDESPREAD CHANCES OF SHOWERS AHEAD OF A 500MB VORT MAX. PREVIOUS DISCUSSION...THE LONGWAVE TROUGH AXIS WILL BE CENTERED ACROSS THE LOWER GREAT LAKES AS WE MOVE INTO THE MIDWEEK...RESULTING IN A COOL AND UNSETTLED START TO THE PERIOD. THE COMBINATION OF DPVA AND COLDER AIR ALOFT ASSOCIATED WITH THE TROUGH WILL MAKE TUESDAY NIGHT AND WEDNESDAY MORNING THE MOST UNSETTLED PART OF THE PERIOD. IN FACT...WITH 850MB TEMPS FALLING TO +8C TO +10C AND CYCLONIC WESTERLY FLOW IN PLACE ACROSS THE AREA...IT IS QUITE POSSIBLE THAT WE COULD SEE THE DEVELOPMENT OF LAKE EFFECT RAIN SHOWERS DOWNSTREAM OF LAKE ERIE...AND TO A GREATER EXTENT EAST OF OF LAKE ONTARIO WHERE LONGER FETCH SHOULD COMPENSATE FOR THE LACK OF DEEP MOISTURE. AS ELUDED TO ABOVE...AREAS DOWNWIND OF LAKE ERIE WILL BE ON THE SOUTHERN FRINGE OF THE DEEPER SYNOPTIC MOISTURE...HENCE THE LOWER POPS ACROSS WESTERN NY. HOWEVER IT IS WORTH NOTING THAT A STRONG VORT MAX IS PROGGED TO BE CROSSING THE FORECAST AREA OVERNIGHT...AND THIS WILL YIELD AT LEAST A CHANCE OF SHOWERS ELSEWHERE. NONETHELESS...EVEN WHERE WE DON'T SEE LAKE EFFECT SHOWERS...WE WILL LIKELY SEE AN ABUNDANCE OF CLOUD COVER. THE COOL AIR ASSOCIATED WITH THE TROUGH WILL YIELD LOWS IN THE 50S EXCEPT FOR IMMEDIATELY ALONG THE LAKE WHERE TEMPS WILL BOTTOM OUT AROUND 60. ANY LINGERING SHOWERS SHOULD TAPER OFF WEDNESDAY MORNING AS THE MAIN VORT MAX MOVES INTO EASTERN NEW YORK AND DIURNAL HEATING DISRUPTS ANY LINGERING LAKE EFFECT SHOWERS. HOWEVER WE MAY SEE A RESURGENCE OF SHOWER ACTIVITY EAST OF LAKE ONTARIO BY WEDNESDAY AFTERNOON AS THE CORE OF THE UPPER LEVEL TROUGH WILL STILL BE OVERHEAD THE NORTH COUNTRY AND EASTERN NEW YORK WITH A DECENT AMOUNT OF DIURNAL CLOUDINESS ELSEWHERE ACROSS THE FORECAST AREA ALONG WITH SEASONABLY COOL TEMPERATURES FEATURING HIGHS IN THE LOWER 70S. THE CORE OF THE COLD AIR ALOFT WILL MOVE ACROSS THE REGION WEDNESDAY NIGHT...CAUSING TEMPERATURES TO RUN A COUPLE OF DEGREES COOLER WITH LOWS IN THE LOW TO MID 50S EXCEPT IMMEDIATELY ALONG THE LAKESHORES WHERE LOWS RUN CLOSE TO THE 60 DEGREE MARK. UNLIKE TUESDAY NIGHT...LAKE EFFECT SHOWERS ARE NOT EXPECTED TO BE AN ISSUE OWING TO INCREASINGLY DRY AIR ALOFT AND NOMINALLY STRONGER SHEAR. HOWEVER...WE MAY SEE A FEW AREAS OF LAKE-INDUCED CLOUDINESS LINGER EAST OF LAKE ONTARIO AS THE BACK EDGE OF THE TROUGH MOVES THROUGH THE AREA. CONDITIONS WILL REMAIN DRY THURSDAY AND THURSDAY NIGHT AS THE UPPER LEVEL TROUGH GIVES WAY TO ZONAL FLOW ALOFT. THE QUESTION MARK IS A STORM SYSTEM PROGGED TO CROSS THE OHIO VALLEY AND CENTRAL APPALACHIANS THURSDAY AND THURSDAY NIGHT. THIS SYSTEM MAY BRING A FEW SHOWERS TO THE SOUTHERN TIER DEPENDING ON HOW FAR NORTH IT DRIFTS...HOWEVER FOR NOW WILL MAINTAIN LOW CHANCE POPS FOR THE TIME BEING. WITH NO SIGNIFICANT TEMPERATURE ADVECTION GOING ON...TEMPERATURES WILL RUN CLOSE TO WEDNESDAY/WEDNESDAY NIGHT'S READINGS WITH HIGHS IN THE LOWER 70S AND LOWS IN THE 50S. && .LONG TERM /FRIDAY THROUGH MONDAY/... THE LONGWAVE TROUGH WILL MAINTAIN ITS POSITION OVER EASTERN CANADA THROUGH THE WEEKEND AS A SERIES OF SHORTWAVES MOVING ALONG THE U.S. CANADIAN BORDER WILL LIKELY RE-AMPLIFY THE TROUGH ACROSS THE GREAT LAKES. WHILE THERE ARE CONSIDERABLE DIFFERENCES ON THE DETAILS IN THE EVOLUTION OF THIS SCENARIO...THIS GENERAL TREND SUGGESTS THAT WE WILL SEE AT LEAST A CHANCE OF SHOWERS THIS WEEKEND WITH TEMPERATURES THAT WILL CONTINUE TO RUN ON THE COOLER SIDE OF AVERAGE. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... FOR THE REST OF THE NIGHTTIME HOURS...VFR CONDITIONS WILL CONTINUE TO PREVAIL WITH JUST A FEW LIGHT SHOWERS EXITING INTERIOR PORTIONS OF THE WESTERN SOUTHERN TIER...AND ALSO PUSHING ACROSS LAKE ONTARIO INTO THE NORTH COUNTRY. DUE TO THE LIGHT NATURE OF THE SHOWERS... THESE WILL BE UNLIKELY TO PRODUCE REDUCTIONS IN VSBY. OF MORE CONCERN WILL BE THE POTENTIAL FOR PATCHY FOG DEVELOPMENT WITHIN THE INTERIOR VALLEYS OF THE SOUTHERN TIER AND FROM PORTIONS OF THE FINGER LAKES NORTHEASTWARD INTO OSWEGO COUNTY...WHERE SOME IFR/MVFR RESTRICTIONS IN VSBY WILL BE POSSIBLE. ANY SUCH FOG THAT DEVELOPS SHOULD THEN MIX OUT FAIRLY QUICKLY EARLY TUESDAY MORNING...LEAVING BEHIND GENERAL VFR CONDITIONS THROUGH LATE MORNING/MIDDAY. AFTER THAT TIME...THE COMBINATION OF AN APPROACHING SECONDARY COLD FRONT AND DIURNAL HEATING WILL LEAD TO INCREASING CLOUD COVER AND THE DEVELOPMENT OF SCATTERED TO NUMEROUS SHOWERS AND POSSIBLE THUNDERSTORMS TUESDAY AFTERNOON AND EVENING... ANY OF WHICH COULD PRODUCE RESTRICTIONS TO IFR/MVFR. THE FRONT ITSELF WILL CROSS THE REGION TUESDAY NIGHT...WITH DRYING AND SUBSIDENCE IN ITS WAKE LEADING TO A RETURN TO DRIER WEATHER/VFR CONDITIONS IN MOST LOCATIONS OVERNIGHT...THOUGH THE SHOWERS WILL LIKELY LINGER THROUGH THE NIGHT EAST OF LAKE ONTARIO OWING TO A COMBINATION OF UPSLOPE FLOW AND INCREASING LAKE INFLUENCES. OUTLOOK... WEDNESDAY...SCATTERED SHOWERS/POSSIBLE MVFR ACROSS THE NORTH COUNTRY AND SAINT LAWRENCE VALLEY...OTHERWISE VFR. THURSDAY THROUGH MONDAY...VFR. && .MARINE... A FALL LIKE AIRMASS IN THE WAKE OF A SECOND COLD FRONT COULD SET THE STAGE FOR WATERSPOUTS ON LAKE ONTARIO TUESDAY NIGHT AND WEDNESDAY. BUFKIT SOUNDINGS SHOW STEEP CONVECTIVE CLOUD DEPTHS AND LAKE-850 DELTA-TS OF AROUND 15C WHICH FIT THE SZILAGYI WATERSPOUT NOMOGRAM POTENTIAL FOR UPPER LOW WATERSPOUTS. A SLIGHT CHANCE HAS BEEN ADDED INTO THE FORECAST OVER THE LAKES. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...JJR NEAR TERM...APFFEL/JJR SHORT TERM...SMITH/WOOD LONG TERM...WOOD AVIATION...JJR MARINE...APFFEL/JJR  FXUS61 KBUF 101509 AFDBUF AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BUFFALO NY 1109 AM EDT MON AUG 10 2015 .SYNOPSIS... A SLOW MOVING FRONTAL BOUNDARY OVER WISCONSIN WILL APPROACH OUR REGION TODAY WITH SHOWERS AND THUNDERSTORMS BECOMING INCREASINGLY LIKELY OVER THE WESTERN NEW YORK BEFORE SPREADING EAST. AN AREA OF LOW PRESSURE WILL THEN TRACK NORTHEAST ALONG THIS FRONT AND CROSS OUR REGION TONIGHT. THIS WILL GENERATE WIDESPREAD SHOWERS AND THUNDERSTORMS...SOME OF WHICH WILL INCLUDE HEAVY RAIN. UNSETTLED WEATHER WILL CONTINUE ON TUESDAY WHEN ADDITIONAL SHOWERS CAN BE EXPECTED. && .NEAR TERM /THROUGH TONIGHT/... THE MAIN WEATHER FOCUS THROUGH TONIGHT IS ON THE ARRIVAL OF SOME VERY BENEFICIAL RAIN FOR WESTERN AND NORTH CENTRAL NEW YORK. THERE WILL BE A FINE LINE BETWEEN BENEFICIAL AND PROBLEMATIC THOUGH...AS THERE WILL BE THE RISK THAT SOME AREAS COULD EXPERIENCE MULTIPLE...SLOW MOVING DOWNPOURS. LATE THIS MORNING RADAR SHOWS SHOWER AND THUNDERSTORM ACTIVITY IS FOCUSED OVER LAKE HURON INTO MICHIGAN. THIS WILL APPROACH WESTERN NEW YORK INTO THE AFTERNOON. ALL THE INGREDIENTS ARE COMING TOGETHER FOR THIS BENEFICIAL RAIN EVENT. A PAIR OF ROBUST SHORTWAVES ONE PUSHING ACROSS LAKE SUPERIOR AND THE OTHER MOVING ACROSS ILLINOIS WILL CARVE OUT A DEEP LONGWAVE TROUGH OVER THE GREAT LAKES. THIS DIGGING ENERGY IN THE MID LEVELS WILL 'ACTIVATE' A WEAK SURFACE TROUGH...THAT AT 15Z STILL EXTENDED FROM THE U.P. OF MICHIGAN SOUTH ACROSS ILLINOIS TO MISSOURI. CYCLOGENESIS WITHIN THE TROUGH IS BEGINNING TO DEVELOP A SURFACE LOW OVER MICHIGAN THAT WILL MOVE TO LAKE ERIE BY THIS EVENING. A 40KT LOW LEVEL JET WILL DEVELOP AHEAD OF THIS SFC LOW AND HELP TO TRANSPORT COPIOUS AMOUNTS OF GULF MOISTURE UP ACROSS OUR FORECAST AREA. MESOANALYSIS INDICATES THIS REGION OF HIGH PWATS IS JUST TO OUR WEST WITH MAXES OF 1.7 INCHES OVER MICHIGAN. AS THESE PWATS SHIFT EAST AND RISE TOWARD 2 INCHES WITH THE LOW LEVEL JET...GEFS ENSEMBLE ANOMALIES INDICATE THESE LEVELS ARE 2-3 SD ABOVE NORMAL. VERY LIGHT SYNOPTIC FLOW TODAY WILL LIKELY LEAD TO A CONVERGENT BOUNDARY...POSSIBLY A LAKE BREEZE BOUNDARY...THAT MESO MODELS SHOW WILL PARALLEL LAKE ERIE AND WILL ROUGHLY EXTEND FROM THE CHAUTAUQUA RIDGE TO NORTHERN ERIE COUNTY AND ORLEANS COUNTY. AS OUR AIRMASS DESTABILIZES AND LOW LEVEL MOISTURE INCREASES...SHOWERS AND THUNDERSTORMS WILL FOCUS WITHIN THIS CONVERGENCE AREA. NAM BUFKIT PROFILE SHOW THE ELEVATED PWATS...DEEP WARM CLOUD DEPTHS AND SHORT MBE VECTORS WHICH ALL POINT TOWARD THE RISK OF MULTIPLE STORMS MOVING OVER THE SAME AREA WITH AN ENHANCED RISK FOR HEAVY RAIN THIS AFTERNOON. AS THE AFOREMENTIONED 40KT LOW LEVEL JET SHIFTS EAST ACROSS THE GENESEE VALLEY AND FINGER LAKES THIS EVENING THE DEEP LIFT PROVIDED BY THE UPPER LEVEL JET AND CONVERGENCE AHEAD OF THE CONSOLIDATING SFC LOW...THE ANOMALOUSLY STRONG LOW LEVEL JET WILL HELP TO FEED BACK BUILDING THUNDERSTORMS. THERE COULD BE AREAS THAT RECEIVE WELL OVER AN INCH OF RAIN IN LESS THAN 90 MINUTES. WHILE ONE AND THREE HOUR FLASH FLOOD GUIDANCE VALUES ARE GREATER THAN THAT...THERE COULD STILL BE THE RISK FOR ISOLATED FLASH FLOOD ISSUES. THIS WILL REMAIN HIGHLIGHTED IN THE HAZARDOUS WEATHER OUTLOOK. AS WE PUSH THROUGH TONIGHT...THE SFC LOW WILL TRACK FROM THE LAKE ERIE SHORE NORTHEAST ACROSS EASTERN LAKE ONTARIO.MEANWHILE THE ENHANCED AREA OF UL LIFT WILL ADVANCE EASTWARD ACROSS THE STATE. THIS WILL SHIFT THE AREA OF MOST WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY TO THE EASTERN LAKE ONTARIO REGION FOR THE WEE HOURS OF TUESDAY MORNING. HAVE BUMPED POPS TO 100 FOR THE ENTIRE CWA...WITH RAINFALL THROUGH TONIGHT FORECAST TO AVERAGE AN INCH IN MOST AREAS TO AN INCH AND A HALF OVER PARTS OF THE GENESEE VALLEY AND FINGER LAKES REGION. LOCALLY HIGHER AMOUNTS WILL BE POSSIBLE. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... TUESDAY MORNING A SURFACE LOW WILL BE FOUND NEAR THE VICINITY OF THE HEADWATERS OF THE SAINT LAWRENCE RIVER...WITH THE GFS THE FASTEST WITH THE TRACK OF THE LOW...PLACING THE CENTER OF THE LOW NEAR THE ONTARIO/QUEBEC BORDER. THE NAM/CANADIAN/ECMWF ARE ALL SLOWER WITH THE STORM SYSTEM...LEAVING THE LOW AND ITS ASSOCIATED COLD FRONT OVER CENTRAL NEW YORK TO START THE TIME PERIOD. A CONSENSUS OF THESE MODELS WILL LEAD TO ONGOING RAIN SHOWERS/EMBEDDED THUNDER TO START THE DAY OVER OUR EASTERN ZONES...WHILE ACROSS WNY LIGHTER AND MORE SCATTERED IN NATURE RAIN SHOWERS WILL BE FOUND WITH A SECOND SHORTWAVE BRINGING THE UPPER LEVEL TROUGH AXIS TOWARDS THE EASTERN GREAT LAKES REGION. AS THIS SECONDARY SHORTWAVE PASSES THE REGION TUESDAY AFTERNOON AND OVERNIGHT EXPECT AN INCREASE IN SHOWER ACTIVITY WITH AGAIN LIKELY POPS PLACE OVER MUCH OF THE BUFFALO CWA. THOUGH INSTABILITY WILL NOT BE AS GREAT AS MONDAY THERE WILL REMAIN A FAIR AMOUNT...WITH SBCAPE VALUES AROUND 500 J/KG LEADING TO ISOLATED POSSIBILITY FOR A THUNDERSTORM. THIS SECONDARY SHORTWAVE WILL ALSO BRING MUCH COOLER AIR ALOFT WITH TEMPERATURES AT 850 HPA DROPPING TO AROUND 8C BY WEDNESDAY MORNING. THERE WILL CONTINUE TO BE LOW CHANCE POSSIBILITIES FOR SHOWERS TUESDAY NIGHT AND WEDNESDAY. IN ADDITION TO THE SYNOPTIC SHOWERS...LAKE EFFECT RAIN SHOWERS WILL BE POSSIBLE SOUTHEAST OF THE GREAT LAKES TUESDAY NIGHT AND INTO WEDNESDAY. UPPER LEVEL TROUGH OF LOW PRESSURE WILL REMAIN OVER EASTERN CANADA AND THE NORTHEAST U.S. WEDNESDAY NIGHT...THOUGH AT THE SURFACE AN AREA OF HIGH PRESSURE WILL PUSH TOWARDS OUR REGION FROM THE CENTRAL GREAT LAKES REGION. THIS AREA OF HIGH PRESSURE WILL BRING A DRIER AIRMASS AND BRING A REDUCTION TO THE AMOUNT OF SHOWERS. TEMPERATURES TUESDAY WILL BE COOLER...WITH HIGHS IN THE LOW TO MID 70S...AND THEN NOTICEABLY COOLER WEDNESDAY WITH HIGHS ONLY IN THE MID TO UPPER 60S. && .LONG TERM /THURSDAY THROUGH SUNDAY/... FOR THURSDAY AND CONTINUING TOWARDS THE BEGINNING PART OF THE WEEKEND BROAD TROUGHING WANTS TO STAY IN PLACE NEAR HUDSON BAY. THIS WILL KEEP TEMPERATURES OVERALL SLIGHTLY BELOW NORMAL WITH SLIGHTLY ABOVE NORMAL CHANCES OF PRECIPITATION. MORE SPECIFICALLY...ON THURSDAY RISING HEIGHTS BEHIND A DEPARTING UPPER-LEVEL LOW WILL ALLOW TEMPERATURES TO MODERATE SOME... BUT STILL STAY SLIGHTLY COOLER THAN NORMAL. THURSDAY ALSO HAS THE BEST CHANCE OF STAYING DRY. BY FRIDAY A SHORTWAVE PASSING TO OUR NORTH SHOULD FORCE A SLOW-MOVING COLD FRONTAL BOUNDARY INTO THE FORECAST AREA BEFORE STALLING OUT FRIDAY NIGHT. THIS WILL BRING PRECIPITATION CHANCES BACK INTO THE FORECAST FOR FRIDAY AND FRIDAY NIGHT. SATURDAY WILL TREND TOWARDS DRIER BEHIND THE FRONTAL BOUNDARY THOUGH WITH THE SURFACE HIGH STILL REMAINING WELL TO OUR WEST OVER THE WESTERN GREAT LAKES REGION AND UPPER LEVEL TROUGH STILL NEARBY CANNOT RULE OUT A POSSIBLE SHOWER OR TWO TO START THE WEEKEND. SUNDAY BOTH THE 00Z GFS AND ECMWF BRING AN AREA OF HIGH PRESSURE AT THE SURFACE AND RIDGING ALOFT TOWARDS THE REGION. THIS WILL CREATE A MOSTLY SUNNY SKY TO CLOSE OUT THE WEEKEND WITH SEASONABLE TEMPERATURES. && .AVIATION /15Z MONDAY THROUGH FRIDAY/... VFR CONDITIONS IN PLACE LATE THIS MORNING WILL GRADUALLY DETERIORATE FROM THE SOUTHWEST LATER TODAY...WITH WIDESPREAD MVFR TO IFR CONDITIONS ANTICIPATED TONIGHT. THE DEGRADING CONDITIONS WILL COME AS A RESULT OF INCREASING LOW LEVEL MOISTURE AND INSTABILITY LEADING TO SHOWERS AND THUNDERSTORMS OVER THE WESTERN COUNTIES DURING THE MIDDAY AND AFTERNOON...WITH MVFR CONDITIONS POSSIBLE IN THUNDERSTORMS FOR SITES SUCH AS KJHW...KBUF AND KIAG. WIDESPREAD SHOWERS AND THUNDERSTORMS...SOME WITH SLOW MOVING DOWNPOURS...CAN THEN BE EXPECTED TONIGHT AS MVFR CONDITIONS WILL LIKELY FURTHER DETERIORATE TO IFR. THIS WILL ESPECIALLY BE THE CASE OVER THE WESTERN COUNTIES...AND IN PARTICULAR...OVER THE HIGHER TERRAIN WHERE LIFR CIGS WILL BE LIKELY. OUTLOOK... TUESDAY...MVFR TO POSSIBLY IFR IN WIDESPREAD SHOWERS AND ISOLATED THUNDERSTORMS. WEDNESDAY...MVFR WITH LAKE EFFECT CLOUDS AND A CHANCE OF SHOWERS. THURSDAY...VFR. FRIDAY...MAINLY VFR. A CHANCE OF SHOWERS LATE. && .MARINE... WHILE WINDS AND WAVES WILL REMAIN WELL BELOW SMALL CRAFT ADVISORY LEVELS TODAY AND TONIGHT...THE GENERAL WEATHER WILL CERTAINLY DETERIORATE. A SLOW MOVING...FRONTAL BOUNDARY STRETCHING FROM THE UPPER GREAT LAKES TO THE MID WEST WILL PUSH EAST TODAY AND INITIATE AN INCREASING NUMBER OF SHOWERS AND THUNDERSTORMS OVER LAKE ERIE AND THE WESTERN TWO THIRDS OF LAKE ONTARIO. MEANWHILE... MARINERS IN THE THOUSAND ISLANDS REGION AND ST LAWRENCE RIVER SHOULD BE ABLE TO ENJOY ONE MORE FAIRLY NICE DAY TO BE ON THE WATER. LOW PRESSURE DEVELOPING ALONG THE COMPLEX FRONTAL BOUNDARY WILL TRACK ACROSS THE LOWER GREAT LAKES TONIGHT. THIS WILL GENERATE WIDESPREAD SHOWERS THUNDERSTORMS ACROSS THE WHOLE REGION. WINDS WILL FRESHEN IN THE WAKE OF THE EXITING SFC LOW ON TUESDAY AND ESPECIALLY TUESDAY NIGHT. THIS WILL LIKELY LEAD TO A PERIOD WHEN SMALL CRAFT ADVISORIES WILL BE NEEDED. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...RSH/SMITH NEAR TERM...RSH/SMITH SHORT TERM...THOMAS LONG TERM...CHURCH/THOMAS AVIATION...RSH/SMITH MARINE...RSH/SMITH  FXUS61 KBUF 101853 AFDBUF AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BUFFALO NY 253 PM EDT MON AUG 10 2015 .SYNOPSIS... AN AREA OF LOW PRESSURE OVER THE OHIO VALLEY THIS AFTERNOON WILL TRACK NORTHEAST ACROSS WESTERN AND CENTRAL NEW YORK TONIGHT. THIS WILL GENERATE WIDESPREAD SHOWERS AND THUNDERSTORMS...SOME OF WHICH WILL INCLUDE HEAVY RAIN. CHANCES OF SHOWERS WILL LINGER TUESDAY AND WEDNESDAY WITH BELOW NORMAL TEMPERATURES AS AN UPPER LEVEL TROUGH SLOWLY CROSSES THE EASTERN GREAT LAKES. SURFACE RIDGING SHOULD BRING DRY WEATHER THURSDAY. && .NEAR TERM /THROUGH TUESDAY/... REGIONAL RADARS THIS AFTERNOON DISPLAY WIDESPREAD SHOWERS AND ISOLATED THUNDERSTORMS ACROSS EASTERN MICHIGAN SOUTH INTO THE OHIO VALLEY WHICH HAVE FORMED AHEAD OF DEVELOPING LOW PRESSURE AND LEADING LOW LEVEL JET NEAR THE WESTERN END OF LAKE ERIE AND ROBUST SHORTWAVE PRESSING ACROSS THE MIDWEST STATES. SOUTHERNLY FLOW AHEAD OF THE SURFACE LOW IS TRANSPORTING A VERY MOIST AIRMASS WITH PWATS TO 1.8 INCHES NORTH ACROSS THE OHIO VALLEY INTO WESTERN NEW YORK. THIS WILL BE THE AIRMASS WHICH BRINGS A SOAKING BENEFICIAL RAIN TO WESTERN AND NORTH-CENTRAL NEW YORK INTO TONIGHT. MORE LOCALLY...SHOWER AND ISOLATED THUNDERSTORM IS DEVELOPING ALONG AN INSTABILITY AND CONVERGENCE AXIS FROM JAMESTOWN TO ROCHESTER AND SYRACUSE. FORECAST MODELS SHIFT THE VERY MOIST AIRMASS FROM THE OHIO VALLEY THIS AFTERNOON EAST OVER NEW YORK INTO TONIGHT. THERE IS POTENTIAL FOR PWATS TO RISE TOWARD 2 INCHES AS THE LOW THE LOW LEVEL JET STRENGTHENS...GEFS ENSEMBLE ANOMALIES INDICATE THESE LEVELS WOULD BE 2-3 SD ABOVE NORMAL. THE ELEVATED PWATS ALONG WITH NAM BUFKIT PROFILES SHOWING INCREASING WARM CLOUD DEPTHS AND SHORT MBE VECTORS ALL POINT TOWARD THE RISK OF MULTIPLE STORMS MOVING OVER THE SAME AREA WITH AN ENHANCED RISK FOR HEAVY RAIN THIS AFTERNOON INTO TONIGHT. QPF THIS AFTERNOON AND EVENING AVERAGES 1-1.5 INCHES WITH LOCALLY 2 OR MORE INCHES POSSIBLE IN TRAINING CELLS. WHILE ONE AND THREE HOUR FLASH FLOOD GUIDANCE VALUES ARE GREATER THAN THAT...THERE COULD STILL BE THE RISK FOR ISOLATED FLASH FLOOD ISSUES. THIS WILL REMAIN HIGHLIGHTED IN THE HAZARDOUS WEATHER OUTLOOK. ANOTHER RISK THIS AFTERNOON IS POTENTIAL FOR SOME ISOLATED STRONG TO SEVERE CELLS DEVELOPING THIS IS CONFINED TO THE SOUTHERN TIER WHERE BULK WIND SHEAR OF 20-30 KTS IS PRESENT PER RECENT MESOANALYSIS. SPC MAINTAINS A MARGINAL RISK FOR SEVERE WEATHER HERE WITH THE MAIN THREAT BEING POSSIBLE DAMAGING WINDS. TONIGHT...WIDESPREAD RAINFALL...HEAVY AT TIMES...IS EXPECTED AS THE PREVIOUSLY MENTIONED SURFACE LOW...LEADING LOW LEVEL JET AND HIGH PWAT AREA TRACK ACROSS WESTERN AND CENTRAL NEW YORK AHEAD OF A SHARPENING MID-LEVEL TROUGH. THE CORE OF THE LOW LEVEL JET AND LARGEST MOISTURE TRANSPORT VECTORS ARE FORECAST TO TRACK ACROSS THE FINGER LAKES INTO THE NORTH COUNTY WHERE THE HIGHEST RAINFALL TOTALS SHOULD BE OBSERVED. IN ADDITION TO THE RAINFALL THE SOAKING RAINS WILL LIKELY CONTRIBUTE TO PATCHY FOG OVERNIGHT AND KEEP MILD TEMPERATURES OVERNIGHT. LOWS WILL ONLY SLIP BACK INTO THE LOW TO MID 60S. ON TUESDAY THE DEEPENING SURFACE LOW AND NEWLY FORMED SOUTHWARD EXTENDING COLD FRONT WILL QUICKLY EXIT EAST OF CENTRAL AND NORTHERN NEW YORK. LINGERING WRAP AROUND MOISTURE AND UPSLOPE FLOW WITH COOLING TEMPERATURES ALOFT WILL KEEP CHANCES OF SHOWERS AND AN ISOLATED THUNDERSTORM IN THE FORECAST. COVERAGE WILL BE MUCH LOWER THAN THE WIDESPREAD RAINS COMING THIS EVENING. WEAK COLD AIR ADVECTION WILL HELP CAP AFTERNOON TEMPERATURES NEAR THE MID 70S. WIDESPREAD CLOUD COVER IN THE MORNING SHOULD DEVELOP SOME BREAKS IN THE AFTERNOON AS MOISTURE PROFILES THIN. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... TUESDAY MORNING A SURFACE LOW WILL BE FOUND NEAR THE VICINITY OF THE HEADWATERS OF THE SAINT LAWRENCE RIVER...WITH THE GFS THE FASTEST WITH THE TRACK OF THE LOW...PLACING THE CENTER OF THE LOW NEAR THE ONTARIO/QUEBEC BORDER. THE NAM/CANADIAN/ECMWF ARE ALL SLOWER WITH THE STORM SYSTEM...LEAVING THE LOW AND ITS ASSOCIATED COLD FRONT OVER CENTRAL NEW YORK TO START THE TIME PERIOD. A CONSENSUS OF THESE MODELS WILL LEAD TO ONGOING RAIN SHOWERS/EMBEDDED THUNDER TO START THE DAY OVER OUR EASTERN ZONES...WHILE ACROSS WNY LIGHTER AND MORE SCATTERED IN NATURE RAIN SHOWERS WILL BE FOUND WITH A SECOND SHORTWAVE BRINGING THE UPPER LEVEL TROUGH AXIS TOWARDS THE EASTERN GREAT LAKES REGION. AS THIS SECONDARY SHORTWAVE PASSES THE REGION TUESDAY AFTERNOON AND OVERNIGHT EXPECT AN INCREASE IN SHOWER ACTIVITY WITH AGAIN LIKELY POPS PLACE OVER MUCH OF THE BUFFALO CWA. THOUGH INSTABILITY WILL NOT BE AS GREAT AS MONDAY THERE WILL REMAIN A FAIR AMOUNT...WITH SBCAPE VALUES AROUND 500 J/KG LEADING TO ISOLATED POSSIBILITY FOR A THUNDERSTORM. THIS SECONDARY SHORTWAVE WILL ALSO BRING MUCH COOLER AIR ALOFT WITH TEMPERATURES AT 850 HPA DROPPING TO AROUND 8C BY WEDNESDAY MORNING. THERE WILL CONTINUE TO BE LOW CHANCE POSSIBILITIES FOR SHOWERS TUESDAY NIGHT AND WEDNESDAY. IN ADDITION TO THE SYNOPTIC SHOWERS...LAKE EFFECT RAIN SHOWERS WILL BE POSSIBLE SOUTHEAST OF THE GREAT LAKES TUESDAY NIGHT AND INTO WEDNESDAY. UPPER LEVEL TROUGH OF LOW PRESSURE WILL REMAIN OVER EASTERN CANADA AND THE NORTHEAST U.S. WEDNESDAY NIGHT...THOUGH AT THE SURFACE AN AREA OF HIGH PRESSURE WILL PUSH TOWARDS OUR REGION FROM THE CENTRAL GREAT LAKES REGION. THIS AREA OF HIGH PRESSURE WILL BRING A DRIER AIRMASS AND BRING A REDUCTION TO THE AMOUNT OF SHOWERS. TEMPERATURES TUESDAY WILL BE COOLER...WITH HIGHS IN THE LOW TO MID 70S...AND THEN NOTICEABLY COOLER WEDNESDAY WITH HIGHS ONLY IN THE MID TO UPPER 60S. && .LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/... FOR THURSDAY AND CONTINUING TOWARDS THE BEGINNING PART OF THE WEEKEND BROAD TROUGHING WANTS TO STAY IN PLACE NEAR HUDSON BAY. THIS WILL KEEP TEMPERATURES OVERALL SLIGHTLY BELOW NORMAL WITH SLIGHTLY ABOVE NORMAL CHANCES OF PRECIPITATION. MORE SPECIFICALLY...ON THURSDAY RISING HEIGHTS BEHIND A DEPARTING UPPER-LEVEL LOW WILL ALLOW TEMPERATURES TO MODERATE SOME... BUT STILL STAY SLIGHTLY COOLER THAN NORMAL. THURSDAY ALSO HAS THE BEST CHANCE OF STAYING DRY. BY FRIDAY A SHORTWAVE PASSING TO OUR NORTH SHOULD FORCE A SLOW-MOVING COLD FRONTAL BOUNDARY INTO THE FORECAST AREA BEFORE STALLING OUT FRIDAY NIGHT. THIS WILL BRING PRECIPITATION CHANCES BACK INTO THE FORECAST FOR FRIDAY AND FRIDAY NIGHT. SATURDAY WILL TREND TOWARDS DRIER BEHIND THE FRONTAL BOUNDARY THOUGH WITH THE SURFACE HIGH STILL REMAINING WELL TO OUR WEST OVER THE WESTERN GREAT LAKES REGION AND UPPER LEVEL TROUGH STILL NEARBY CANNOT RULE OUT A POSSIBLE SHOWER OR TWO TO START THE WEEKEND. SUNDAY BOTH THE 00Z GFS AND ECMWF BRING AN AREA OF HIGH PRESSURE AT THE SURFACE AND RIDGING ALOFT TOWARDS THE REGION. THIS WILL CREATE A MOSTLY SUNNY SKY TO CLOSE OUT THE WEEKEND WITH SEASONABLE TEMPERATURES. && .AVIATION /19Z MONDAY THROUGH SATURDAY/... AN AXIS OF -SHRA/-TSRA EXTENDS FROM KERI NORTHEAST TO KROC AT 18Z. EXPECT TEMPO MVFR/IFR WITHIN THIS ACTIVITY AS IT TRACKS OVER THE TERMINALS. VFR CONDITIONS OUTSIDE OF SHRA/TSRA WILL GRADUALLY DETERIORATE FROM THE SOUTHWEST THIS EVENING AS INCREASING LOW LEVEL MOISTURE AND LARGE SCALE LIFT LEADS TO WIDESPREAD SHOWERS AND ISOLATED THUNDERSTORMS APPROACHING FROM THE OHIO VALLEY THIS EVENING. THE WIDESPREAD SHOWERS AND ISOLATED THUNDERSTORMS WILL FEATURE POCKETS OF HEAVY RAIN WHICH WILL LOWER CIGS TO IFR LEVELS TONIGHT WITH PATCHY FOG POSSIBLY REDUCING VIS. THE WIDESPREAD RAIN WILL PIVOT EAST OVERNIGHT AND TAPER TO VCSH FROM WEST TO EAST TOWARD 12Z. A RETURN TO VFR IS EXPECTED TOMORROW AFTER DAYBREAK BUT LINGERING MOISTURE AND A MID-LEVEL TROUGH OVER THE EASTERN GREAT LAKES WILL KEEP CHANCES FOR SHOWERS INTO THE AFTERNOON. OUTLOOK... TUESDAY NIGHT...MVFR IN SCATTERED SHOWERS. WEDNESDAY...MVFR WITH LAKE EFFECT CLOUDS AND A CHANCE OF SHOWERS. THURSDAY...VFR. FRIDAY...MAINLY VFR. A CHANCE OF SHOWERS LATE. SATURDAY...MAINLY VFR EXPECTED. && .MARINE... A DEVELOPING LOW PRESSURE NEAR THE WEST END OF LAKE ERIE WILL PUSH EAST TONIGHT BRINGING WIDESPREAD SHOWERS AND THUNDERSTORMS TO THE EASTERN GREAT LAKES THIS EVENING AND OVERNIGHT. WINDS AND WAVES SHOULD REMAIN BELOW SMALL CRAFT ADVISORY LEVELS. WINDS WILL FRESHEN IN THE WAKE OF THE EXITING SFC LOW ON TUESDAY AND ESPECIALLY TUESDAY NIGHT. THIS WILL MAY LEAD TO A PERIOD WHEN SMALL CRAFT ADVISORIES COULD BE NEEDED. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...SMITH NEAR TERM...SMITH SHORT TERM...APFFEL LONG TERM...APFFEL AVIATION...SMITH MARINE...SMITH  FXUS61 KBUF 102008 AFDBUF AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BUFFALO NY 408 PM EDT MON AUG 10 2015 .SYNOPSIS... AN AREA OF LOW PRESSURE OVER THE OHIO VALLEY WILL TRACK NORTHEAST ACROSS WESTERN AND CENTRAL NEW YORK TONIGHT. THIS WILL GENERATE WIDESPREAD SHOWERS AND THUNDERSTORMS...SOME OF WHICH WILL INCLUDE HEAVY RAIN. CHANCES OF SHOWERS WILL LINGER TUESDAY AND WEDNESDAY WITH BELOW NORMAL TEMPERATURES AS AN UPPER LEVEL TROUGH SLOWLY CROSSES THE EASTERN GREAT LAKES. SURFACE RIDGING SHOULD BRING DRY WEATHER THURSDAY. && .NEAR TERM /THROUGH TUESDAY/... REGIONAL RADARS EARLY THIS EVENING DISPLAY WIDESPREAD SHOWERS AND SCATTERED THUNDERSTORMS EXTENDING FROM EASTERN MICHIGAN SOUTH INTO OHIO AND NORTHEAST ACROSS LAKE ERIE TO TORONTO. THESE HAVE FORMED AHEAD OF DEVELOPING LOW PRESSURE AND ITS LEADING LOW LEVEL JET NEAR THE WESTERN END OF LAKE ERIE AND A ROBUST SHORTWAVE PRESSING INTO THE OHIO VALLEY. SOUTHERNLY FLOW AHEAD OF THE SURFACE LOW IS TRANSPORTING A VERY MOIST AIRMASS WITH PWATS TO 1.8 INCHES NORTH ACROSS THE OHIO VALLEY INTO WESTERN NEW YORK. THIS WILL BE THE AIRMASS WHICH BRINGS A SOAKING BUT MAINLY BENEFICIAL RAIN TO WESTERN AND NORTH-CENTRAL NEW YORK INTO TONIGHT. MORE LOCALLY...SHOWERS AND THUNDERSTORMS EXTEND ALONG AN INSTABILITY AND CONVERGENCE AXIS FROM JAMESTOWN TO ROCHESTER AND SOUTH OF LAKE ONTARIO TOWARD SYRACUSE. SOME OF THIS ACTIVITY HAS ALREADY PRODUCED VERY HEAVY RAIN IN SLOW MOVING/BACKBUILDING CELLS EAST OF ROCHESTER. MORE ON THIS BELOW. FORECAST MODELS SHIFT THE VERY MOIST AIRMASS FROM THE OHIO VALLEY EAST OVER NEW YORK INTO TONIGHT. THERE IS POTENTIAL FOR PWATS TO RISE TOWARD 2 INCHES AS THE LOW THE LOW LEVEL JET STRENGTHENS...GEFS ENSEMBLE ANOMALIES INDICATE THESE LEVELS WOULD BE 2-3 SD ABOVE NORMAL. THE ELEVATED PWATS ALONG WITH NAM BUFKIT PROFILES SHOWING INCREASING WARM CLOUD DEPTHS AND SHORT MBE VECTORS ALL POINT TOWARD THE ENHANCED RISK FOR HEAVY RAIN THIS INTO TONIGHT. QPF THROUGH TONIGHT AVERAGES 1-1.5 INCHES REGIONWIDE WITH LOCALLY 2 OR MORE INCHES POSSIBLE IN TRAINING CELLS. WHILE ONE AND THREE HOUR FLASH FLOOD GUIDANCE VALUES ARE GREATER THAN THAT...THERE REMAINS THE RISK FOR ISOLATED FLASH FLOOD ISSUES. ANOTHER RISK THIS EVENING IS POTENTIAL FOR SOME ISOLATED STRONG TO SEVERE CELLS DEVELOPING THIS IS CONFINED TO THE SOUTHERN TIER WHERE BULK WIND SHEAR OF 20-30 KTS IS PRESENT PER RECENT MESOANALYSIS. SPC MAINTAINS A MARGINAL RISK FOR SEVERE WEATHER HERE WITH THE MAIN THREAT BEING POSSIBLE DAMAGING WINDS. TONIGHT...WIDESPREAD RAINFALL...HEAVY AT TIMES...IS EXPECTED AS THE PREVIOUSLY MENTIONED SURFACE LOW...LEADING LOW LEVEL JET AND HIGH PWAT AREA TRACK ACROSS WESTERN AND CENTRAL NEW YORK AHEAD OF A SHARPENING MID-LEVEL TROUGH. THE CORE OF THE LOW LEVEL JET AND LARGEST MOISTURE TRANSPORT VECTORS ARE FORECAST TO TRACK ACROSS THE FINGER LAKES INTO THE NORTH COUNTY WHERE THE HIGHEST RAINFALL TOTALS SHOULD BE OBSERVED. IN ADDITION TO THE RAINFALL THE SOAKING RAINS WILL LIKELY CONTRIBUTE TO PATCHY FOG OVERNIGHT AND KEEP MILD TEMPERATURES OVERNIGHT. LOWS WILL ONLY SLIP BACK INTO THE LOW TO MID 60S. ON TUESDAY THE DEEPENING SURFACE LOW AND NEWLY FORMED SOUTHWARD EXTENDING COLD FRONT WILL QUICKLY EXIT EAST OF CENTRAL AND NORTHERN NEW YORK. LINGERING WRAP AROUND MOISTURE AND UPSLOPE FLOW WITH COOLING TEMPERATURES ALOFT WILL KEEP CHANCES OF SHOWERS AND AN ISOLATED THUNDERSTORM IN THE FORECAST. COVERAGE WILL BE MUCH LOWER THAN THE WIDESPREAD RAINS COMING THIS EVENING. WEAK COLD AIR ADVECTION WILL HELP CAP AFTERNOON TEMPERATURES NEAR THE MID 70S. WIDESPREAD CLOUD COVER IN THE MORNING SHOULD DEVELOP SOME BREAKS IN THE AFTERNOON AS MOISTURE PROFILES THIN. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... TUESDAY MORNING A SURFACE LOW WILL BE FOUND NEAR THE VICINITY OF THE HEADWATERS OF THE SAINT LAWRENCE RIVER...WITH THE GFS THE FASTEST WITH THE TRACK OF THE LOW...PLACING THE CENTER OF THE LOW NEAR THE ONTARIO/QUEBEC BORDER. THE NAM/CANADIAN/ECMWF ARE ALL SLOWER WITH THE STORM SYSTEM...LEAVING THE LOW AND ITS ASSOCIATED COLD FRONT OVER CENTRAL NEW YORK TO START THE TIME PERIOD. A CONSENSUS OF THESE MODELS WILL LEAD TO ONGOING RAIN SHOWERS/EMBEDDED THUNDER TO START THE DAY OVER OUR EASTERN ZONES...WHILE ACROSS WNY LIGHTER AND MORE SCATTERED IN NATURE RAIN SHOWERS WILL BE FOUND WITH A SECOND SHORTWAVE BRINGING THE UPPER LEVEL TROUGH AXIS TOWARDS THE EASTERN GREAT LAKES REGION. AS THIS SECONDARY SHORTWAVE PASSES THE REGION TUESDAY AFTERNOON AND OVERNIGHT EXPECT AN INCREASE IN SHOWER ACTIVITY WITH AGAIN LIKELY POPS PLACE OVER MUCH OF THE BUFFALO CWA. THOUGH INSTABILITY WILL NOT BE AS GREAT AS MONDAY THERE WILL REMAIN A FAIR AMOUNT...WITH SBCAPE VALUES AROUND 500 J/KG LEADING TO ISOLATED POSSIBILITY FOR A THUNDERSTORM. THIS SECONDARY SHORTWAVE WILL ALSO BRING MUCH COOLER AIR ALOFT WITH TEMPERATURES AT 850 HPA DROPPING TO AROUND 8C BY WEDNESDAY MORNING. THERE WILL CONTINUE TO BE LOW CHANCE POSSIBILITIES FOR SHOWERS TUESDAY NIGHT AND WEDNESDAY. IN ADDITION TO THE SYNOPTIC SHOWERS...LAKE EFFECT RAIN SHOWERS WILL BE POSSIBLE SOUTHEAST OF THE GREAT LAKES TUESDAY NIGHT AND INTO WEDNESDAY. UPPER LEVEL TROUGH OF LOW PRESSURE WILL REMAIN OVER EASTERN CANADA AND THE NORTHEAST U.S. WEDNESDAY NIGHT...THOUGH AT THE SURFACE AN AREA OF HIGH PRESSURE WILL PUSH TOWARDS OUR REGION FROM THE CENTRAL GREAT LAKES REGION. THIS AREA OF HIGH PRESSURE WILL BRING A DRIER AIRMASS AND BRING A REDUCTION TO THE AMOUNT OF SHOWERS. TEMPERATURES TUESDAY WILL BE COOLER...WITH HIGHS IN THE LOW TO MID 70S...AND THEN NOTICEABLY COOLER WEDNESDAY WITH HIGHS ONLY IN THE MID TO UPPER 60S. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... FOR THURSDAY AND CONTINUING TOWARDS THE BEGINNING PART OF THE WEEKEND BROAD TROUGHING WANTS TO STAY IN PLACE NEAR HUDSON BAY. THIS WILL KEEP TEMPERATURES OVERALL SLIGHTLY BELOW NORMAL WITH SLIGHTLY ABOVE NORMAL CHANCES OF PRECIPITATION. MORE SPECIFICALLY...ON THURSDAY RISING HEIGHTS BEHIND A DEPARTING UPPER-LEVEL LOW WILL ALLOW TEMPERATURES TO MODERATE SOME... BUT STILL STAY SLIGHTLY COOLER THAN NORMAL. THURSDAY ALSO HAS THE BEST CHANCE OF STAYING DRY. BY FRIDAY A SHORTWAVE PASSING TO OUR NORTH SHOULD FORCE A SLOW-MOVING COLD FRONTAL BOUNDARY INTO THE FORECAST AREA BEFORE STALLING OUT FRIDAY NIGHT. THIS WILL BRING PRECIPITATION CHANCES BACK INTO THE FORECAST FOR FRIDAY AND FRIDAY NIGHT. SATURDAY WILL TREND TOWARDS DRIER BEHIND THE FRONTAL BOUNDARY THOUGH WITH THE SURFACE HIGH STILL REMAINING WELL TO OUR WEST OVER THE WESTERN GREAT LAKES REGION AND UPPER LEVEL TROUGH STILL NEARBY CANNOT RULE OUT A POSSIBLE SHOWER OR TWO TO START THE WEEKEND. SUNDAY BOTH THE 00Z GFS AND ECMWF BRING AN AREA OF HIGH PRESSURE AT THE SURFACE AND RIDGING ALOFT TOWARDS THE REGION. THIS WILL CREATE A MOSTLY SUNNY SKY TO CLOSE OUT THE WEEKEND WITH SEASONABLE TEMPERATURES. && .AVIATION /20Z MONDAY THROUGH SATURDAY/... AN AXIS OF -SHRA/-TSRA EXTENDS FROM KERI NORTHEAST TO KROC AT 20Z. EXPECT TEMPO MVFR/IFR WITHIN THIS ACTIVITY AS IT TRACKS OVER/NEAR THE TERMINALS. VFR CONDITIONS OUTSIDE OF SHRA/TSRA WILL GRADUALLY DETERIORATE FROM THE SOUTHWEST THIS EVENING AS INCREASING LOW LEVEL MOISTURE AND LARGE SCALE LIFT LEADS TO WIDESPREAD SHOWERS AND ISOLATED THUNDERSTORMS APPROACHING FROM THE OHIO VALLEY THIS EVENING. THE WIDESPREAD SHOWERS AND ISOLATED THUNDERSTORMS WILL FEATURE POCKETS OF HEAVY RAIN WHICH WILL LOWER CIGS TO IFR LEVELS TONIGHT WITH PATCHY FOG POSSIBLY REDUCING VIS. THE WIDESPREAD RAIN WILL PIVOT EAST OVERNIGHT AND TAPER TO VCSH FROM WEST TO EAST TOWARD 12Z. A RETURN TO VFR IS EXPECTED TOMORROW AFTER DAYBREAK BUT LINGERING MOISTURE AND A MID-LEVEL TROUGH OVER THE EASTERN GREAT LAKES WILL KEEP CHANCES FOR SHOWERS INTO THE AFTERNOON. OUTLOOK... TUESDAY NIGHT...MVFR IN SCATTERED SHOWERS. WEDNESDAY...MVFR WITH LAKE EFFECT CLOUDS AND A CHANCE OF SHOWERS. THURSDAY...VFR. FRIDAY...MAINLY VFR. A CHANCE OF SHOWERS LATE. SATURDAY...MAINLY VFR EXPECTED. && .MARINE... A DEVELOPING LOW PRESSURE NEAR THE WEST END OF LAKE ERIE WILL PUSH EAST TONIGHT BRINGING WIDESPREAD SHOWERS AND THUNDERSTORMS TO THE EASTERN GREAT LAKES THIS EVENING AND OVERNIGHT. WINDS AND WAVES SHOULD REMAIN BELOW SMALL CRAFT ADVISORY LEVELS. WINDS WILL FRESHEN IN THE WAKE OF THE EXITING SFC LOW ON TUESDAY AND ESPECIALLY TUESDAY NIGHT. THIS WILL MAY LEAD TO A PERIOD WHEN SMALL CRAFT ADVISORIES COULD BE NEEDED. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...SMITH NEAR TERM...SMITH SHORT TERM...APFFEL LONG TERM...APFFEL AVIATION...SMITH MARINE...SMITH  FXUS61 KBUF 102346 AFDBUF AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BUFFALO NY 746 PM EDT MON AUG 10 2015 .SYNOPSIS... AN AREA OF LOW PRESSURE OVER THE OHIO VALLEY WILL TRACK NORTHEAST ACROSS WESTERN AND CENTRAL NEW YORK TONIGHT. THIS WILL GENERATE WIDESPREAD SHOWERS AND THUNDERSTORMS...SOME OF WHICH WILL INCLUDE HEAVY RAIN. CHANCES OF SHOWERS WILL LINGER TUESDAY AND WEDNESDAY WITH BELOW NORMAL TEMPERATURES AS AN UPPER LEVEL TROUGH SLOWLY CROSSES THE EASTERN GREAT LAKES. SURFACE RIDGING SHOULD BRING DRY WEATHER THURSDAY. && .NEAR TERM /THROUGH TUESDAY/... REGIONAL RADARS SHOWING WIDESPREAD SHOWERS AND A FEW SCATTERED THUNDERSTORMS ACROSS THE BULK OF THE REGION WITH AREAS OF EMBEDDED HEAVY RAINFALL. ADDITIONAL SHOWERS AND STORMS ACROSS NORTH CENTRAL OHIO AND LAKE ERIE WILL LIFT NORTHEAST ACROSS THE REGION OVERNIGHT AS LOW PRESSURE CROSSES THE REGION. FORECAST MODELS SHIFT THE VERY MOIST AIRMASS FROM THE OHIO VALLEY EAST OVER NEW YORK INTO TONIGHT. THERE IS POTENTIAL FOR PWATS TO RISE TOWARD 2 INCHES AS THE LOW THE LOW LEVEL JET STRENGTHENS... GEFS ENSEMBLE ANOMALIES INDICATE THESE LEVELS WOULD BE 2-3 SD ABOVE NORMAL. THE ELEVATED PWATS ALONG WITH NAM BUFKIT PROFILES SHOWING INCREASING WARM CLOUD DEPTHS AND SHORT MBE VECTORS ALL POINT TOWARD THE ENHANCED RISK FOR HEAVY RAIN THIS INTO TONIGHT. QPF THROUGH TONIGHT AVERAGES 1-1.5 INCHES REGIONWIDE WITH LOCALLY 2 OR MORE INCHES POSSIBLE IN TRAINING CELLS. WHILE ONE AND THREE HOUR FLASH FLOOD GUIDANCE VALUES ARE GREATER THAN THAT...THERE REMAINS THE RISK FOR ISOLATED FLASH FLOOD ISSUES WHERE SHORT TERM RAINFALL RATES ARE EXCESSIVELY HIGH. THE SEVERE WEATHER RISK IS NOW GONE WITH WIDESPREAD CONVECTION EATING UP THE LIMITED AVAILABLE INSTABILITY. EVEN THE AMOUNT OF THUNDER PERIOD HAS DROPPED OFF SIGNIFICANTLY OVER THE PAST HOUR. TONIGHT...WIDESPREAD RAINFALL...HEAVY AT TIMES...IS EXPECTED AS THE PREVIOUSLY MENTIONED SURFACE LOW...LEADING LOW LEVEL JET AND HIGH PWAT AREA TRACK ACROSS WESTERN AND CENTRAL NEW YORK AHEAD OF A SHARPENING MID-LEVEL TROUGH. THE CORE OF THE LOW LEVEL JET AND LARGEST MOISTURE TRANSPORT VECTORS ARE FORECAST TO TRACK ACROSS THE FINGER LAKES INTO THE NORTH COUNTY WHERE THE HIGHEST RAINFALL TOTALS SHOULD BE OBSERVED FROM LATE EVENING ON. IN ADDITION TO THE RAINFALL THE SOAKING RAINS WILL LIKELY CONTRIBUTE TO PATCHY FOG OVERNIGHT AND KEEP MILD TEMPERATURES OVERNIGHT. LOWS WILL ONLY SLIP BACK INTO THE LOW TO MID 60S. ON TUESDAY THE DEEPENING SURFACE LOW AND NEWLY FORMED SOUTHWARD EXTENDING COLD FRONT WILL QUICKLY EXIT EAST OF CENTRAL AND NORTHERN NEW YORK. LINGERING WRAP AROUND MOISTURE AND UPSLOPE FLOW WITH COOLING TEMPERATURES ALOFT WILL KEEP CHANCES OF SHOWERS AND AN ISOLATED THUNDERSTORM IN THE FORECAST. COVERAGE WILL BE MUCH LOWER THAN THE WIDESPREAD RAINS COMING THIS EVENING. WEAK COLD AIR ADVECTION WILL HELP CAP AFTERNOON TEMPERATURES NEAR THE MID 70S. WIDESPREAD CLOUD COVER IN THE MORNING SHOULD DEVELOP SOME BREAKS IN THE AFTERNOON AS MOISTURE PROFILES THIN. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... TUESDAY MORNING A SURFACE LOW WILL BE FOUND NEAR THE VICINITY OF THE HEADWATERS OF THE SAINT LAWRENCE RIVER...WITH THE GFS THE FASTEST WITH THE TRACK OF THE LOW...PLACING THE CENTER OF THE LOW NEAR THE ONTARIO/QUEBEC BORDER. THE NAM/CANADIAN/ECMWF ARE ALL SLOWER WITH THE STORM SYSTEM...LEAVING THE LOW AND ITS ASSOCIATED COLD FRONT OVER CENTRAL NEW YORK TO START THE TIME PERIOD. A CONSENSUS OF THESE MODELS WILL LEAD TO ONGOING RAIN SHOWERS/EMBEDDED THUNDER TO START THE DAY OVER OUR EASTERN ZONES...WHILE ACROSS WNY LIGHTER AND MORE SCATTERED IN NATURE RAIN SHOWERS WILL BE FOUND WITH A SECOND SHORTWAVE BRINGING THE UPPER LEVEL TROUGH AXIS TOWARDS THE EASTERN GREAT LAKES REGION. AS THIS SECONDARY SHORTWAVE PASSES THE REGION TUESDAY AFTERNOON AND OVERNIGHT EXPECT AN INCREASE IN SHOWER ACTIVITY WITH AGAIN LIKELY POPS PLACE OVER MUCH OF THE BUFFALO CWA. THOUGH INSTABILITY WILL NOT BE AS GREAT AS MONDAY THERE WILL REMAIN A FAIR AMOUNT...WITH SBCAPE VALUES AROUND 500 J/KG LEADING TO ISOLATED POSSIBILITY FOR A THUNDERSTORM. THIS SECONDARY SHORTWAVE WILL ALSO BRING MUCH COOLER AIR ALOFT WITH TEMPERATURES AT 850 HPA DROPPING TO AROUND 8C BY WEDNESDAY MORNING. THERE WILL CONTINUE TO BE LOW CHANCE POSSIBILITIES FOR SHOWERS TUESDAY NIGHT AND WEDNESDAY. IN ADDITION TO THE SYNOPTIC SHOWERS...LAKE EFFECT RAIN SHOWERS WILL BE POSSIBLE SOUTHEAST OF THE GREAT LAKES TUESDAY NIGHT AND INTO WEDNESDAY. UPPER LEVEL TROUGH OF LOW PRESSURE WILL REMAIN OVER EASTERN CANADA AND THE NORTHEAST U.S. WEDNESDAY NIGHT...THOUGH AT THE SURFACE AN AREA OF HIGH PRESSURE WILL PUSH TOWARDS OUR REGION FROM THE CENTRAL GREAT LAKES REGION. THIS AREA OF HIGH PRESSURE WILL BRING A DRIER AIRMASS AND BRING A REDUCTION TO THE AMOUNT OF SHOWERS. TEMPERATURES TUESDAY WILL BE COOLER...WITH HIGHS IN THE LOW TO MID 70S...AND THEN NOTICEABLY COOLER WEDNESDAY WITH HIGHS ONLY IN THE MID TO UPPER 60S. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... FOR THURSDAY AND CONTINUING TOWARDS THE BEGINNING PART OF THE WEEKEND BROAD TROUGHING WANTS TO STAY IN PLACE NEAR HUDSON BAY. THIS WILL KEEP TEMPERATURES OVERALL SLIGHTLY BELOW NORMAL WITH SLIGHTLY ABOVE NORMAL CHANCES OF PRECIPITATION. MORE SPECIFICALLY...ON THURSDAY RISING HEIGHTS BEHIND A DEPARTING UPPER-LEVEL LOW WILL ALLOW TEMPERATURES TO MODERATE SOME... BUT STILL STAY SLIGHTLY COOLER THAN NORMAL. THURSDAY ALSO HAS THE BEST CHANCE OF STAYING DRY. BY FRIDAY A SHORTWAVE PASSING TO OUR NORTH SHOULD FORCE A SLOW-MOVING COLD FRONTAL BOUNDARY INTO THE FORECAST AREA BEFORE STALLING OUT FRIDAY NIGHT. THIS WILL BRING PRECIPITATION CHANCES BACK INTO THE FORECAST FOR FRIDAY AND FRIDAY NIGHT. SATURDAY WILL TREND TOWARDS DRIER BEHIND THE FRONTAL BOUNDARY THOUGH WITH THE SURFACE HIGH STILL REMAINING WELL TO OUR WEST OVER THE WESTERN GREAT LAKES REGION AND UPPER LEVEL TROUGH STILL NEARBY CANNOT RULE OUT A POSSIBLE SHOWER OR TWO TO START THE WEEKEND. SUNDAY BOTH THE 00Z GFS AND ECMWF BRING AN AREA OF HIGH PRESSURE AT THE SURFACE AND RIDGING ALOFT TOWARDS THE REGION. THIS WILL CREATE A MOSTLY SUNNY SKY TO CLOSE OUT THE WEEKEND WITH SEASONABLE TEMPERATURES. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... WIDESPREAD SHOWERS AND SCATTERED THUNDERSTORMS WILL CONTINUE TONIGHT ACROSS THE REGION. CIGS AND VSBY ARE INITIALLY A MIX OF VFR AND MVFR WITH MVFR FOUND ONLY IN THE HEAVIER SHOWERS. THIS WILL CONTINUE TO BE THE CASE THROUGH THE REST OF THE EVENING. OVERNIGHT THE AXIS OF STEADIER RAIN WILL SHIFT SLOWLY EAST AND BE FOUND ACROSS CENTRAL AND EASTERN NY BY TUESDAY MORNING. IN THE WAKE OF THE STEADIER RAINFALL...MOIST NORTHWEST FLOW WILL DEVELOP BEHIND THE DEPARTING LOW PRESSURE. THIS WILL SET THE STAGE FOR WIDESPREAD IFR FROM ABOUT 06Z-14Z TUESDAY WITH WRAP AROUND MOISTURE AND NORTHWEST UPSLOPE FLOW DEVELOPING. EXPECT CIGS TO RAPIDLY DETERIORATE TO IFR AROUND 06Z EVEN AT THE LOWER ELEVATION SITES. PATCHY FOG/BR WILL ALSO DEVELOP WITH VSBY DROPPING TO AT LEAST MVFR...AND POSSIBLY IFR ACROSS HIGHER TERRAIN WHERE THE LOW STRATUS WILL INTERSECT THE HILLS. BY LATE TUESDAY MORNING THE LOW STRATUS AND FOG WILL BEGIN TO LIFT WITH CIGS/VSBY IMPROVING THROUGH MVFR AND EVENTUALLY VFR DURING THE AFTERNOON. SOME MVFR CIGS MAY LINGER ACROSS HIGHER TERRAIN. THERE WILL STILL BE SCATTERED SHOWERS AROUND WITH WRAP AROUND MOISTURE... SOME INSTABILITY...AND THE APPROACH OF A MID LEVEL TROUGH. OUTLOOK... TUESDAY NIGHT...MVFR IN SCATTERED SHOWERS. WEDNESDAY...MVFR WITH LAKE EFFECT CLOUDS AND A CHANCE OF SHOWERS. THURSDAY...VFR. FRIDAY...MAINLY VFR. A CHANCE OF SHOWERS LATE. SATURDAY...MAINLY VFR EXPECTED. && .MARINE... A DEVELOPING LOW PRESSURE NEAR THE WEST END OF LAKE ERIE WILL PUSH EAST TONIGHT BRINGING WIDESPREAD SHOWERS AND THUNDERSTORMS TO THE EASTERN GREAT LAKES THIS EVENING AND OVERNIGHT. WINDS AND WAVES SHOULD REMAIN BELOW SMALL CRAFT ADVISORY LEVELS. WINDS WILL FRESHEN IN THE WAKE OF THE EXITING SFC LOW ON TUESDAY AND ESPECIALLY TUESDAY NIGHT. THIS WILL MAY LEAD TO A PERIOD WHEN SMALL CRAFT ADVISORIES COULD BE NEEDED. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...SMITH NEAR TERM...HITCHCOCK/SMITH SHORT TERM...APFFEL LONG TERM...APFFEL AVIATION...HITCHCOCK MARINE...SMITH  FXUS61 KBUF 181620 AFDBUF AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BUFFALO NY 1220 PM EDT SAT JUL 18 2015 .SYNOPSIS... VERY WARM AND HUMID AIR WILL OVERSPREAD THE REGION THIS WEEKEND... AND BRING AN INCREASED CHANCE OF SCATTERED SHOWERS AND THUNDERSTORMS. A COLD FRONT WILL CROSS THE REGION SUNDAY EVENING... AND WILL BE ACCOMPANIED BY A MORE ORGANIZED LINE OF SHOWERS AND THUNDERSTORMS. && .NEAR TERM /THROUGH SUNDAY/... IT WILL BE A VERY WARM AND HUMID DAY TODAY WITH HIGH TEMPERATURES IN THE 80S AND DEWPOINTS IN THE UPPER 60S TO LOW 70S. A SOUTHWEST FLOW SHOULD RESULT IN SLIGHTLY COOLER TEMPERATURES NORTHEAST OF THE LAKES...INCLUDING THE BUFFALO AND WATERTOWN AREAS. ABUNDANT LOW-LEVEL MOISTURE WILL FUEL SOME DIURNALLY DRIVEN INSTABILITY SHOWERS AND THUNDERSTORMS TODAY. HOWEVER...A LACK OF SIGNIFICANT FORCING MECHANISMS WILL LIMIT THE COVERAGE OF ANY CONVECTIVE ACTIVITY. A WEAK STALLED SURFACE BOUNDARY REMAINS ORIENTED ACROSS LAKE ONTARIO... WITH THE HIGHER DEW POINT AIR ON THE SOUTHERN SIDE OF THE BOUNDARY. THIS STALLED BOUNDARY WILL INTERACT WITH THE LAKE BREEZE OFF LAKE ONTARIO TO ACT AS ONE AREA OF FOCUS FOR SHOWERS AND THUNDERSTORMS THIS AFTERNOON SOUTH OF LAKE ONTARIO... FROM NIAGARA COUNTY THROUGH ROCHESTER TO OSWEGO COUNTY. EXPECT ACTIVITY TO BE FAIRLY SCATTERED AND THUS HAVE KEPT POPS MAXED OUT AT 40S IN THIS AXIS. OTHERWISE... OROGRAPHIC ASCENT COMBINED WITH THE INLAND PUSHING LAKE ERIE LAKE BREEZE SHOULD SPARK OFF A FEW SCATTERED SHOWERS AND THUNDERSTORMS ACROSS INTERIOR PORTIONS OF THE SOUTHERN TIER WHICH WILL MOVE OFF INTO THE FINGER LAKES REGION. ANY THUNDERSTORMS WILL BE EFFICIENT RAINMAKERS AND COULD CAUSE AREAS OF LOCALIZED FLOODING...ESPECIALLY WITH PRECIPITABLE WATER VALUES FORECAST TO EXCEED 1.5 INCHES IN MANY LOCATIONS... AND SLOW/TRAINING STORM MOTIONS ALONG THE STALLED FRONT. SUNDAY WILL BE THE WARMEST DAY THUS FAR THIS SUMMER SEASON. A PROGRESSIVE SHORTWAVE RIDGE WILL PUSH ACROSS OUR REGION SATURDAY NIGHT AND SUNDAY WITH A VERY SULTRY AIRMASS ARRIVING FROM THE OHIO VALLEY. THIS OPPRESSIVE AIRMASS WILL INCLUDE DEW POINTS IN THE LOWER 70S...WHICH WHEN COMBINED WITH TEMPERATURES IN THE LOWER 90S...WILL PRODUCE APPARENT TEMPERATURES CLOSE TO 100. ALONG WITH BEING HOT AND QUITE HUMID ON SUNDAY...THERE WILL BE THE RISK FOR STRONG THUNDERSTORMS. WHILE MOST OF THE DAY WILL BE RAIN FREE...OUR AIRMASS WILL BECOME QUITE UNSTABLE DURING THE LATE AFTERNOON AND EVENING AS SURFACE BASED CAPES ARE FORECAST TO CLIMB TO NEAR 2000 J/KG. THUNDERSTORMS WILL BE INITIATED ALONG A PRE FRONTAL TROUGH THAT WILL PUSH ACROSS THE WESTERN COUNTIES DURING THE MIDDAY HOURS. AS THIS FEATURE MOVES TO THE FINGER LAKES AND FURTHER EAST...INCREASED INSTABILUTY COULD SUPPORT STRONG TO SEVERE CONVECTION. && .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/... THE MAIN FOCUS DURING THIS PERIOD WILL BE A COLD FRONTAL PASSAGE SUNDAY NIGHT THAT WILL PRODUCE STRONG TO SEVERE THUNDERSTORMS... ALTHOUGH THE MAIN CONCERN WILL LIKELY BE FLOODING. STORMY WEATHER SHOULD ALREADY BE UNDERWAY ACROSS THE FAR WESTERN COUNTIES AS WE OPEN THIS PERIOD...AS A COLD FRONT WILL BE BEARING DOWN ON OUR FORECAST AREA FROM SOUTHERN ONTARIO. OUR AIRMASS WILL STILL BE RATHER OPPRESSIVE AS DEW POINT TEMPERATURES WILL BE WITHIN A COUPLE DEGREES OF 70. BACKWARD TRAJECTORIES FROM THE GFS CONTINUE TO SUPPORT THAT THE WEALTH OF LOW LEVEL MOISTURE WILL BE SUPPLEMENTED IN THE MID LEVELS BY A PLUME OF TROPICAL MOISTURE EXTENDING ACROSS THE COUNTRY FROM THE REMNANTS OF WHAT SHOULD BE POST-TROPICAL 'DOLORES' OFF BAJA CALIFORNIA. THIS DEEP MOISTURE FIELD WILL PRODUCE PWAT VALUES OF 1.75 TO 2 INCHES EARLY SUNDAY EVENING...THUS KEEPING THE CONCERN IN PLACE FOR TORRENTIAL DOWNPOURS WITH THE EXPECTED CONVECTION. AIDING IN THE EFFICIENCY OF HEAVY RAIN PRODUCTION WILL BE THE DEEP WARM CLOUD DEPTHS...WHICH WILL BE IN EXCESS OF 12K FT. WHILE IT NOW APPEARS THAT THERE WILL BE ENOUGH FLOW TO KEEP STORMS MOVING ALONG...RECENT HEAVY RAINS HAVE PRODUCED NEAR SATURATED ANTECEDENT CONDITIONS FOR MANY AREAS...SO THE RISK FOR FLASH FLOODING WILL HAVE TO BE CLOSELY MONITORED. THE BAD NEWS IS THAT THE INCREASED FLOW WILL RAISE THE RISK FOR SEVERE WEATHER (DAMAGING WINDS/HAIL). IN TERMS OF THE CONVECTION ITSELF...THERE SHOULD BE ENOUGH SUN FROM THE AFTERNOON LEADING INTO THE EARLY EVENING TO PROMOTE SBCAPES OF MORE THAN 2000 J/KG (LI'S VCNTY OF -8). AS MENTIONED ABOVE...THE GUIDANCE PACKAGES ARE NOW INDICATING STRONG WINDS ALOFT...WHICH WILL LEAD TO BULK SHEAR VALUES OF 40 KNOTS. THIS WOULD CERTAINLY BE ENOUGH TO ALLOW STORMS TO BECOME ORGANIZED AND PERSIST FOR A LONGER PERIOD...LIKELY EVOLVING INTO A LINE OF STRONG CONVECTION THAT COULD INCLUDE DAMAGING WINDS. THE 'FAT CAPE' PROFILES WOULD ALSO SUPPORT THE THREAT FOR LARGE HAIL. ALONG WITH THE MENTION OF HEAVY RAIN... WILL ADD THE MENTION OF GUSTY WINDS AND HAIL TO THE STORMS FOR SUNDAY EVENING. THE BULK OF THE ACTIVITY WILL COME BEFORE MIDNIGHT WITH DRIER MORE STABLE AIR PUSHING ACROSS THE LOWER GREAT LAKES THEREAFTER AS THE FRONT EXITS ACROSS NEW ENGLAND. ON MONDAY...LOW LEVEL RIDGING AND MUCH DRIER AIR WILL PRODUCE A FINE DAY ACROSS OUR REGION WITH AMPLE SUNSHINE AND MORE COMFORTABLE CONDITIONS. WHILE IT WILL BE ON THE WARM SIDE OF NORMAL...TEMPS WILL BE SOME 5 TO 10 DEGREES LOWER THAN THOSE FROM SUNDAY. A COLD FRONT WITH LIMITED MOISTURE WILL APPROACH OUR REGION FROM THE UPPER GREAT LAKES MONDAY NIGHT. HAVE BUMPED THE POPS UP A BIT FOR THE OVERNIGHT HOURS...BUT HAVE KEPT THEM BELOW SLGT CHC FOR NOW. A STRONG MID LEVEL DISTURBANCE DIGGING THROUGH THE BASE OF A DIGGING LONGWAVE TROUGH WILL MAKE ITS WAY ACROSS LAKE ONTARIO ON TUESDAY. WHILE THERE WILL NOT BE A LOT OF MOISTURE TO WORK WITH...HAVE INSERTED LOW CHC POPS FOR SHOWERS AND ISOLATED THUNDERSTORMS. THE BULK OF THE DAY WILL BE RAIN FREE. EXPANSIVE HIGH PRESSURE CENTERED OVER THE MID WEST WILL NOSE TO THE EAST ACROSS THE LOWER GREAT LAKES TUESDAY NIGHT AND WEDNESDAY... WHILE A CYCLONIC FLOW WILL REMAIN IN PLACE IN THE MID AND UPPER LEVELS. THIS WILL GUARANTEE FAIR DRY WEATHER OVER THE WESTERN COUNTIES OF NEW YORK...WITH ONLY THE SLGT CHC FOR AN AFTERNOON SHOWER ACROSS THE EASTERN LAKE ONTARIO REGION. && .LONG TERM /WEDNESDAY THROUGH FRIDAY/... A LOW AMPLITUDE FLOW ALONG THE CANADIAN BORDER WILL FAVOR NEAR NORMAL MID SUMMER TEMPERATURES DURING THIS PERIOD...AS SFC HIGH PRESSURE WILL GENERALLY BE IN CONTROL. && .AVIATION /16Z SATURDAY THROUGH WEDNESDAY/... WIDE AREA OF MVFR STRATUS WILL MIX OUT TO A VFR CUMULUS FIELD BY LATE MORNING. WITH VFR CONDITIONS PREVAILING THIS AFTERNOON. SCATTERED CONVECTION WILL DEVELOP AFTER 15Z WITH HEATING OF THE DAY. THE COMBINATION OF LAKE ONTARIO LAKE BREEZE AND A STALLED FRONTAL BOUNDARY MAY USHER IN SOME SCATTERED CONVECTION ALONG THE SOUTH SHORE OF LAKE ONTARIO... WHICH COULD IMPACT KIAG/KROC. ALSO INLAND PUSHING LAKE BREEZE FROM LAKE ERIE COULD SPARK OFF SOME SCATTERED STORMS NEAR KJHW WHICH WILL PUSH INLAND INTO THE FINGER LAKES REGION BY LATER THIS AFTERNOON. TEMPORARY VIS/CIG RESTRICTIONS TO MVFR/IFR ARE POSSIBLE SHOULD A STRONGER CELL TRACK OVER A TERMINAL. KBUF/KART HAVE THE BEST CHANCES OF STAYING CLEAR TODAY THANKS TO THE STABILIZING INFLUENCE OF LAKES ERIE AND ONTARIO... RESPECTIVELY. OUTLOOK... TONIGHT THROUGH WEDNESDAY...MAINLY VFR THROUGH THE PERIOD. CHANCE FOR SHOWERS AND THUNDERSTORMS WITH BRIEF FLIGHT REDUCTIONS SUNDAY INTO SUNDAY NIGHT AND AGAIN WEDNESDAY. && .MARINE... VERY WARM AND HUMID CONDITIONS EXPECTED THROUGH THE WEEKEND...WITH SOME LOW CHANCES FOR ISOLATED STORMS. THE VERY HUMID AIRMASS WILL ALSO LIKELY RESULT IN AREAS OF FOG DEVELOPING OVER THE COLDER WATERS OF LAKE ONTARIO... WITH A LOWER CHANCE OVER THE WARMER LAKE ERIE. A COLD FRONT WILL MOVE ACROSS THE REGION SUNDAY EVENING BRINGING A MORE ORGANIZED LINE OF THUNDERSTORMS. OUTSIDE OF THUNDERSTORMS...WINDS WILL GENERALLY BE LIGHT AND WAVES 2 FEET OR LESS INTO EARLY NEXT WEEK. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...TMA NEAR TERM...CHURCH/TMA/RSH SHORT TERM...RSH LONG TERM...RSH AVIATION...CHURCH/TMA MARINE...CHURCH/TMA  FXUS61 KBUF 190827 AFDBUF AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BUFFALO NY 427 AM EDT WED AUG 19 2015 .SYNOPSIS... WARM AND HUMID AIR WILL REMAIN OVER THE REGION TODAY WITH A LOW CHANCE OF SHOWERS AND THUNDERSTORMS THIS AFTERNOON. ON THURSDAY A STRONG...SLOW MOVING COLD FRONT WILL CROSS THE AREA BRINGING POTENTIALLY HEAVY RAINFALL. COOLER AND DRIER AIR WILL RETURN BEHIND THE COLD FRONT BRINGING SEASONABLE AND PLEASANT WEATHER FOR THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... RADAR IS SHOWING SCATTERED SHOWERS ACROSS THE GENESEE VALLEY AND NORTH OF THE FINGER LAKES EARLY THIS MORNING AS A WEAK MID-LEVEL SHORTWAVE SHIFTS ACROSS WESTERN NEW YORK. HIGH-RES MODELS INDICATE WIDELY SCATTERED SHOWERS WILL BE POSSIBLE ACROSS THIS REGION DRIFTING FROM SOUTH TO NORTH THROUGH THE PRE-DAWN HOURS. OTHERWISE IR SATELLITE SHOWS MAINLY CLOUDY SKIES WITH A FEW BRIEF BREAKS. TEMPERATURES WILL REMAIN MILD ONLY SLIPPING INTO THE MID/UPPER 60S. THROUGH THE DAYLIGHT HOURS TODAY EXPECTING MAINLY DRY CONDITIONS FOR THE VAST MAJORITY OF THE TIME AS SHORTWAVE RIDGING SHIFTS OVERHEAD. A MOIST AIRMASS PER ~1.5 INCH PWATS ON SPC MESOANALYSIS ALONG WITH NAM BUFKIT FORECAST SOUNDINGS SHOWING WEAK SKINNY CAPE POSSIBLY DEVELOPING DURING THE AFTERNOON HOURS LEAVES A LOWER END CHANCE OF A WIDELY SCATTERED SHOWER OR THUNDERSTORM TODAY. WITHOUT A SYNOPTIC TRIGGER SHOWING UP IN GUIDANCE...PLACEMENT OF POPS IS MORE BROADBRUSH AND WILL BE CONFINED TO MESOSCALE BOUNDARY FORCING. PARTLY TO MOSTLY CLOUDY SKIES ARE EXPECTED WITH DEWPOINTS EDGING UP TOWARD THE UPPER 60S THROUGH THE DAY UNDER SOUTHERLY FLOW AHEAD OF AN APPROACHING COLD FRONT. TEMPERATURES WILL RUN ABOVE NORMAL WITH HIGHS RANGING THROUGH THE 80S. TONIGHT THE COLD FRONT WILL EDGE ACROSS MICHIGAN WITH FRONT-PARALLEL 500MB FLOW CONTROLLING ITS SLOW MOVEMENT. THE BEST FORCING AND MOISTURE CONVERGENCE ALONG/AHEAD OF THE FRONT LOOKS TO HOLD OFF UNTIL THURSDAY BUT A SUBTLE MID-LEVEL WAVE LIFTING ACROSS THE FORECAST AREA MAY TRIGGER SCATTERED SHOWERS OVERNIGHT AHEAD OF THE FRONT. HAVE RAMPED UP POPS THROUGH THE OVERNIGHT HOURS FROM LOW CHANCE TO LIKELY TOWARD 12Z THURSDAY. SOUTHERLY FLOW AND MOSTLY CLOUDY SKIES ALONG WITH ELEVATED DEWPOINTS WILL MAKE FOR ANOTHER MILD AND HUMID NIGHT AHEAD OF THE FRONT. LOWS WILL ONLY SLIP BACK INTO THE UPPER 60S TO LOW 70S. && .SHORT TERM /THURSDAY THROUGH SATURDAY NIGHT/... A DEEPLY STACKED...HIGHLY ANOMALOUS FALL LIKE STORM SYSTEM OVER THE UPPER GREAT LAKES AT THE START OF THIS PERIOD WILL BE THE MAIN CONCERN FOR THIS FORECAST PACKAGE. THIS ATYPICAL SYNOPTIC FEATURE WILL INCLUDE MANY PARAMETERS THAT WILL HAVE SEASONALLY ADJUSTED ANOMALIES OF 3 TO 5 STD...WHICH CLIMATOLOGICALLY TRANSLATES INTO A ONCE IN A GENERATION STORM SYSTEM. SOME OF THESE ELEMENTS WILL BE FURTHER DISCUSSED BELOW...BUT THE ULTIMATE CONCERN IS THAT ALL OF THE SIGNALS WILL BE THERE FOR A SIGNIFICANT CONVECTIVE RAIN EVENT OVER WESTERN AND NORTH CENTRAL NEW YORK. THE DEVIANT STORM SYSTEM WILL BE CENTERED OVER LAKE SUPERIOR ON THURSDAY MORNING...BUT A 110KT H25 JET STREAKING NORTH AROUND ITS EASTERN PERIPHERY WILL QUICKLY ENCOURAGE THE PARENT LONGWAVE TROUGH TO BECOME NEGATIVELY TILTED...THEREBY DIRECTING THE SYSTEM ACROSS NORTHERN ONTARIO TO JAMES BAY. MEANWHILE DOWNSTREAM...A LARGELY SOUTH TO NORTH STEERING FLOW OVER THE LOWER GREAT LAKES WILL GIVE LITTLE FORWARD MOMENTUM TO THE ASSOCIATED SFC COLD FRONT...WHICH WILL BE FURTHER SLOWED BY A TRIPLE POINT/SFC WAVE OVER THE MID- ATLANTIC STATES. THIS IS KEY TO POINT OUT...AS THE SLOW MOVING FRONT WILL GIVE PLENTY OF TIME FOR CONVECTION TO FIRE UP ACROSS OUR AREA AND POINTS SOUTH. THIS CONVECTION WILL BE FED BY A MOISTURE RICH SOUTHERLY 40KT LOW LEVEL JET...WHICH WILL BE SOME 4 STD STRONGER THAN TYPICAL MID AUGUST SRLY WINDS. CONVERGENT PLUMES OF SUB TROPICAL MOISTURE...ONE OUT OF THE GULF OF MEXICO AND THE OTHER FROM THE SE COAST...WILL BE DIRECTED BY THE AFOREMENTIONED WINDS ACROSS THE LOWER GREAT LAKES AND MID ATLANTIC REGION. THIS SCENARIO WILL COME AS A RESULT OF A DEEP SOUTHERLY FLOW THAT WILL BE ESTABLISHED BETWEEN -4 TO -5 STD HGT DEPARTURES OVER THE MID WEST AND +2/3 HGT DEPARTURES OVER THE CANADIAN MARITIMES...A CLASSIC PATTERN FOR A HIGH QPF EVENT. PWAT VALUES WILL EASILY EXCEED 2 INCHES. REFERRING TO RICH GRUMMS FINE WORK ON CLIMATOLOGICAL ANOMALIES...THIS SYSTEM IS LIKELY TO PRODUCE SIGNIFICANT WEATHER IN THE VCNTY OF THE LOWER GREAT LAKES/MID ATLANTIC REGION. THE SLOW MOVING FRONTAL BOUNDARY...WHICH IS STILL BEING HANDLED DIFFERENT BY THE OPERATIONAL GUIDANCE PACKAGES (GFS FASTER/ECMWF SLOWER)...WILL GRUDGINGLY PUSH EAST ACROSS WESTERN NEW YORK DURING THE DAY THURSDAY. OVERALL SYNOPTIC LIFT AHEAD AND ALONG THIS FRONT WILL BE SUPPLIED BY MODERATELY STRONG FRONTOGENETIC FORCING (ESP EAST OF THE GEN VALLEY) AND ALSO FROM BEING IN THE VCNTY OF THE RR QUAD OF THE AFOREMENTIONED 110KT H25 JET. THERMODYNAMICALLY...'TALL SKINNY' CAPES OF 500-1000 J/KG WILL ACCOMPANY A MOISTURE RICH AIRMASS THAT WILL HELP TO PRODUCE WARM CLOUD DEPTHS IN THE VCNTY OF 12K FT. THE CONVECTION INDUCED FROM THIS ENVIRONMENT WILL LARGELY MOVE SOUTH TO NORTH...FAVORING TRAINING OF DOWNPOURS. THIS SHOULD BE EERILY SIMILAR TO WHAT WAS OBSERVED TUESDAY AFTERNOON ACROSS THE FINGER LAKES REGION WHEN FLASH FLOOD WARNINGS WERE ISSUED BY BOTH BUF AND BGM. FOR THIS REASON...WE HAVE DECIDE TO ISSUE A FLASH FLOOD WATCH FOR ALL OF WESTERN AND NORTH CENTRAL NEW YORK. THE WATCH WILL START DURING THE DAY THURSDAY FOR THE WESTERN COUNTIES...BUT WILL NOT START FOR THE EASTERN LAKE ONTARIO REGION UNTIL THURSDAY NIGHT. SPEAKING OF TIMING...THE BULK OF THE SHOWERS AND THUNDERSTORMS ARE FORECAST TO OVER THE WESTERN COUNTIES BETWEEN LATE THURSDAY MORNING AND EARLY THURSDAY NIGHT WHILE SITES EAST OF LAKE ONTARIO ARE EXPECTED TO RECEIVE THEIR GREATEST QPF BETWEEN LATE THURSDAY AFTERNOON THROUGH THURSDAY NIGHT. THIS TIMING IS CONSISTENT WITH THE SLOWER FRONTAL PROGRESSION ADVERTISED FOR DAYS BY THE ECMWF. THE THREAT FOR HEAVY CONVECTIVE RAINS SHOULD END BY MIDNIGHT OR SO OVER THE WESTERN COUNTIES. WILL NOT BE A SLAVE TO MODEL QPF IN THIS CASE AS MODELS ARE NOTORIOUSLY POOR AT CONVECTIVE RAINFALL AMOUNTS AND PLACEMENT. WHILE BASIN AVERAGE AMOUNTS SHOULD BE IN THE VCNTY OF A HALF TO ONE INCH...IT IS VERY CONCEIVABLE THAT STREAKS OF +3 INCH AMOUNTS WILL BE OBSERVED. ON FRIDAY...THE ALREADY SLOW MOVING FRONTAL BOUNDARY WILL BECOME STALLED OVER NEW ENGLAND. THE SYSTEM SHOULD MOVE FAR ENOUGH TO THE EAST THOUGH TO ALLOW THE SHOWERS AND STORMS TO TAPER OFF ACROSS THE NORTH COUNTRY...WHILE SFC BASED RIDGING OVER THE OHIO VALLEY WILL EXTEND NORTH TO PROMOTE INCREASING AMOUNTS OF SUN. IT WILL BE MUCH MORE COMFORTABLE ON FRIDAY AS WELL...AS A REFRESHING CANADIAN AIRMASS IN THE WAKE OF THE FRONT WILL OFFER DEW POINTS IN THE 50S. H85 TEMPS ARE FORECAST TO DROP JUST BELOW 10C...SO THIS SHOULD KEEP FRIDAY AFTERNOON TEMPS FROM CLIMBING OUT OF THE 70S F. FRIDAY NIGHT AND SATURDAY WILL BE BEAUTIFUL AS SFC HIGH PRESSURE WILL DRIFT ACROSS OUR REGION. MAINLY CLEAR SKIES AND LIGHT WINDS FRIDAY NIGHT WILL ENCOURAGE TEMPS TO DROP INTO THE 40S ACROSS MUCH OF THE SRN TIER...WHILE THE REST OF THE FORECAST AREA WILL ENJOY A NIGHT WITH MINS IN THE 50S. SATURDAY WILL FOLLOW WITH PLENTY OF BRIGHT SUNSHINE AND TEMPERATURES ONCE AGAIN TOPPING OUT IN THE 70S. && .LONG TERM /SUNDAY THROUGH TUESDAY/... GENERALLY UNEVENTFUL WEATHER CAN BE EXPECTED DURING THIS PERIOD... ALTHOUGH ITS NOT OUT OF THE QUESTION THAT A CHILLY AIRMASS MOVING IN FROM THE UPPER GREAT LAKES COULD SPAWN SOME WATERSPOUTS OVER LAKES ERIE AND ONTARIO EARLY IN THE WORK WEEK. MORE ON THIS IN A MOMENT. THE SECOND ABNORMALLY DEEP CLOSED LOW IN FIVE DAYS WILL TRACK EAST FROM THE CANADIAN PRAIRIES TO EASTERN CANADA DURING THIS PERIOD... AND THIS WILL EVENTUALLY LEAD TO A DEEP CYCLONIC FLOW OVER THE LOWER GREAT LAKES THAT WILL SUPPORT MORE BELOW NORMAL TEMPERATURES. THE GOOD NEWS IS THAT THERE WILL BE LITTLE IN THE WAY OF PRECIPITATION THOUGH...WITH THE ONLY RAINFALL COMING AS THE LEADING EDGE OF THE FRESH CANADIAN AIRMASS PUSHES OVER THE LOWER GREAT LAKES. TO START THIS PERIOD ON SUNDAY...HIGH PRESSURE WILL REMAIN WEDGED OVER THE LOWER GREAT LAKES AS OUR FORECAST AREA WILL BE SANDWICHED BETWEEN AN APPROACHING COLD FRONT AND DEEPENING ATLANTIC MOISTURE OVER NEW ENGLAND AND THE ADIRONDACKS REGION. THIS SHOULD SUPPORT ONE MORE NICE DAY WITH A FAIR AMOUNT OF SUNSHINE AND TEMPS TOPPING OUT IN THE LOW TO MID 80S. CONDITIONS WILL DETERIORATE SOMEWHAT SUNDAY NIGHT AS A COLD FRONT WILL TAKE AIM ON OUR REGION FROM LOWER MICHIGAN. THIS FRONT WILL CROSS WESTERN AND NORTH CENTRAL NEW YORK ON MONDAY...BUT WITH LIMITED MOISTURE. WILL KNOCK POPS BACK A BIT TO LOW CHC. A DEEP CYCLONIC FLOW WILL THEN BECOME ESTABLISHED IN THE WAKE OF THE FRONT MONDAY NIGHT AND TUESDAY. H85 TEMPS ARE EXPECTED TO DROP TO BETWEEN 6 AND 8C...AND THIS WILL SEND OUR MERCURY TO BELOW NORMAL LEVELS WHILE ESTABLISHING ENOUGH LAKE INDUCED INSTABILITY TO PRODUCE SOME LAKE CLOUDS AND POSSIBLY SOME WATERSPOUTS. WILL USE SLGT CHC POPS FOR ANY NUISANCE SHOWERS THAT MAY DEVELOP WITHIN THIS ENVIRONMENT. MAX TEMPS ON TUESDAY SHOULD GENERALLY RANGE FROM 70 TO 75. && .AVIATION /09Z WEDNESDAY THROUGH SUNDAY/... AS OF 08Z SOME LINGERING SHOWERS FROM KROC TO KFZY WILL LIFT NORTH OVER LAKE ONTARIO WHILE MORE SCATTERED SHOWERS CONTINUE TO BE POSSIBLE NORTH OF THE FINGER LAKES THROUGH THE PREDAWN HOURS. RECENT RAINFALL AND SOME CLEAR BREAKS SHIFTING OVER THE REGION SHOULD ALLOW FOR IFR CIGS AT KJHW FOLLOWING GUIDANCE AND MVFR/IFR VIS AT KART AS DEWPOINT DEPRESSIONS NARROW. VFR CONDITIONS WILL PREVAIL AFTER SUNRISE TODAY. A WARM AND MOIST AIRMASS WILL REMAIN ACROSS THE REGION...BUT WITHOUT A DEFINITIVE TRIGGER TO FOCUS CONVECTION...ANY ACTIVITY THAT DOES DEVELOP WILL REMAIN WIDELY SCATTERED IN THE AFTERNOON AND THUS NOT MENTIONED IN THE TAFS. VFR WILL CONTINUE TONIGHT WITH GRADUALLY LOWERING CIGS AND STEADY SOUTHERLY WINDS AS A COLD FRONT APPROACHES FROM THE WEST. OUTLOOK... THURSDAY...SHOWERS AND THUNDERSTORMS LIKELY. FRIDAY THROUGH SUNDAY...VFR. && .MARINE... SHOWERS OVER THE EASTERN END OF LAKE ONTARIO WILL LIFT NORTH WITH MORE SCATTERED ACTIVITY CONTINUING TO BE POSSIBLE EARLY THIS MORNING. THE POTENTIAL FOR SHOWERS AND THUNDERSTORMS WILL AGAIN BECOME POSSIBLE LATER THIS AFTERNOON AND PARTICULARLY THURSDAY AS A COLD FRONT WILL APPROACH THE LOWER GREAT LAKES... HOWEVER WINDS AND WAVES ARE EXPECTED TO HOLD BELOW SMALL CRAFT ADVISORY LEVELS. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...FLASH FLOOD WATCH FROM THURSDAY AFTERNOON THROUGH LATE THURSDAY NIGHT FOR NYZ006>008. FLASH FLOOD WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR NYZ001>005-010>014-019>021-085. MARINE...NONE. && $$ SYNOPSIS...SMITH NEAR TERM...SMITH SHORT TERM...RSH LONG TERM...RSH AVIATION...SMITH MARINE...SMITH  FXUS61 KBUF 242344 AFDBUF AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BUFFALO NY 744 PM EDT MON AUG 24 2015 .SYNOPSIS... COOLER AIR WILL BUILD INTO THE REGION BEHIND A COLD FRONT WHICH WILL BRING A FALL-LIKE PATTERN WHICH WILL LAST THROUGH THE END OF THE WEEK. THIS WILL RESULT IN BELOW NORMAL TEMPERATURES...WITH QUITE A BIT OF CLOUD COVER AND PERIODIC RAIN SHOWERS. && .NEAR TERM /THROUGH TUESDAY/... A SURFACE COLD FRONT IS EXITING INTO WESTERN NEW ENGLAND THIS EVENING. THE LAST FEW VISIBLE SATELLITE SHOTS OF THE EVENING SHOW VARYING AMOUNTS OF CLOUD COVER ACROSS THE AREA...WITH EXTENSIVE STRATOCU MOVING INTO MUCH OF WESTERN NY AND PORTIONS OF CENTRAL NY. EXPECT THESE CLOUDS TO HANG ON THROUGH AT LEAST LATE EVENING BEFORE MOST OF THE CLOUD COVER FOCUSES NORTHEAST OF LAKES ERIE AND ONTARIO OVERNIGHT AS LAKE EFFECT PROCESSES BEGIN TO TAKE OVER. TEMPERATURES BEHIND THE COLD FRONT ARE NOT THAT COLD YET...HOWEVER 850MB TEMPERATURES WILL DROP DOWN TO AROUND +7C BY DAYBREAK TUESDAY MORNING. THE CAUSE WILL BE THE GRADUAL APPROACH OF AN UPPER LEVEL TROUGH WHICH WILL RESULT IN INCREASING LAKE INDUCED INSTABILITY ON LAKE ERIE AND EVENTUALLY LAKE ONTARIO. IN ADDITION...A CONSENSUS OF HIGH RESOLUTION GUIDANCE FORECASTS A WELL DEFINED SOUTHWESTERLY CONVERGENCE BOUNDARY DEVELOPING ON LAKE ERIE. THIS SHOULD INITIALLY FOCUS SOME RAIN SHOWERS ON BUFFALO AROUND OR SHORTLY AFTER MIDNIGHT...WITH THESE THEN EXPECTED TO DROP SOUTHWARD AS THE APPROACHING UPPER LEVEL SYSTEM PROMPTS A MORE WSW FLOW. FORECAST WILL CARRY A NARROW BAND OF LIKELY POPS WHICH WILL BE ALONG THIS CONVERGENCE BOUNDARY. THE SHOWERS ARE LIKELY TO REMAIN DISORGANIZED AND CELLULAR GIVEN THE TIME OF YEAR AND BACKGROUND BOUNDARY LAYER MIXING WITH THE APPROACH OF THE MID LEVEL TROUGH. THE LAKE EFFECT RAIN SHOWERS OFF LAKE ONTARIO SHOULD REMAIN MORE DISORGANIZED GIVEN THE WEAKER INSTABILITY AND LESS SYNOPTIC SCALE MOISTURE. EXPECT JUST A FEW SCATTERED SHOWERS LATE TONIGHT AND EARLY TUESDAY NORTHEAST OF THE LAKE NEAR THE THOUSAND ISLANDS REGION. LOWS SHOULD MAINLY BE IN THE 50S...WITH SOME UPPER 40S POSSIBLE ACROSS THE INTERIOR VALLEYS ACROSS THE SOUTHERN TIER WHERE THERE SHOULD BE AT LEAST A PARTIAL CLEARING TONIGHT. ON TUESDAY THE UPPER LEVEL TROUGH AXIS WILL GRADUALLY PUSH TOWARD THE REGION WHICH WILL SHIFT 850MB WINDS TO THE WEST AND DISRUPT THE CONVERGENT FLOW ON LAKE ERIE. AS A RESULT...SHOWERS WILL BREAK UP AND SPREAD INLAND WITH HIT OR MISS SHOWERS DURING THE DAY TUESDAY BOTH FROM LAKE EFFECT AND FROM DIURNAL INSTABILITY ENHANCED BY THE CYCLONIC FLOW ALOFT. THERE WILL ALSO BE MOSTLY CLOUDY SKIES WITH HIGHS IN THE UPPER 60S TO LOWER 70S...COOLEST ACROSS THE HIGHER TERRAIN EAST OF LAKE ERIE. && .SHORT TERM /TUESDAY NIGHT THROUGH FRIDAY NIGHT/... A DEEP CLOSED UPPER LOW WILL SLOWLY MEANDER ITS WAY EAST ACROSS NORTHERN ONTARIO AND NORTHERN QUEBEC WHICH WILL RESULT IN AN AUTUMN- LIKE AIRMASS ACROSS THE FORECAST AREA THROUGH THE MID WEEK PERIOD. ASSOCIATED COLD POOL ALOFT SHOULD ALLOW FOR AT LEAST SCATTERED COVERAGE OF INSTABILITY SHOWERS ACROSS THE AREA DURING THE PEAK HEATING CYCLE BOTH TUESDAY AND WEDNESDAY. THE COLDER AIR FILTERING IN WILL DROP 850 MB TEMPERATURES DOWN TO AROUND +6C...YIELDING LAKE DELTA-T VALUES AROUND 15C...MORE THAN SUFFICIENT FOR LAKE EFFECT SHOWERS DOWNWIND OF THE LAKES. ALONG WITH THE LAKE EFFECT RAIN SHOWERS... THE COOL TEMPS ALOFT AND THE LAKE INDUCED INSTABILITY WILL BE CAPABLE OF PRODUCING WATERSPOUTS WITH THE STRONGER CONVECTIVE CLOUDS WITH THE 15C SFC-850MB DELTA-T AND APPROX 20KFT CONVECTIVE CLOUD DEPTH. BY THURSDAY... THE UPPER LOW STARTS TO SHEAR OUT AND TAKE OFF TO THE EAST AS AN OPEN TROUGH. THE FLOW ACROSS THE FORECAST AREA TURNS MORE NORTHWESTERLY AS THE TROUGH EXITS TO OUR EAST. WITH THE COOLER AIR STICKING AROUND THROUGH THE DAY... LOCATIONS SOUTHEAST OF LAKE ONTARIO FROM ROCHESTER ACROSS TO SOUTHERN OSWEGO COUNTY COULD PICK UP SOME LAKE EFFECT SHOWERS THROUGH THE DAY THURSDAY. HIGH PRESSURE WILL NOSE INTO THE REGION THURSDAY NIGHT THROUGH THE END OF THE WEEK WITH A SHIFT IN THE PLACEMENT AND WEAKENING OF ANY REMAINING LAKE EFFECT SHOWERS. TEMPERATURES OVERALL THROUGH THIS PERIOD WILL RUN ABOUT 10 DEGREES BELOW NORMAL...WITH DAYTIME HIGHS IN THE 60S TO AROUND 70 AND NIGHTTIME LOWS MAINLY IN THE UPPER 40S TO LOWER 50S. THERE WILL BE A RETURN TO NEAR NORMAL TEMPS ON FRIDAY WITH HIGHS IN THE MID 70S AND LOWS IN THE LOWER TO MIDDLE 50S. && .LONG TERM /SATURDAY THROUGH MONDAY/... SURFACE HIGH PRESSURE FROM THE LOWER GREAT LAKES TO THE MID ATLANTIC STATES WILL BLOCK THE EASTWARD PROGRESSION OF A PACIFIC WAVE CROSSING THE MIDWESTERN STATES. THIS SHOULD BRING MOSTLY DRY AND WARMER WEATHER TO THE REGION FOR THE WEEKEND AND EARLY NEXT WEEK. THERE WILL BE A LOW CHANCE OF AFTERNOON SHOWERS ACROSS THE SOUTHERN TIER AND TUG HILL PLATEAU SUNDAY AND MONDAY BUT OTHERWISE DRY AND BACK TO SLIGHTLY ABOVE SEASONAL AVERAGE TEMPS. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... LOW PRESSURE WILL REMAIN IN PLACE JUST NORTH OF THE GREAT LAKES THROUGH TUESDAY WITH DEEPER MOISTURE SLOWLY CIRCULATING BACK INTO THE AREA. THIS WILL SET THE STAGE FOR LAKE EFFECT RAIN SHOWERS EAST AND NORTHEAST OF LAKE ERIE LATER TONIGHT THROUGH TUESDAY MORNING. THESE SHOWERS WILL INITIALLY DEVELOP NEAR KBUF BY AROUND 06Z TUE... THEN DRIFT SLOWLY SOUTH AND EAST THROUGH TUESDAY MORNING. LAKE EFFECT SHOWERS WILL BE LESS ORGANIZED NORTHEAST OF LAKE ONTARIO...WITH JUST A FEW SCATTERED SHOWERS ACROSS THE THOUSAND ISLANDS REGION MAINLY NORTH OF KART LATE TONIGHT AND TUESDAY MORNING. CONDITIONS WILL REMAIN MAINLY VFR OVERNIGHT INTO TUESDAY MORNING...WITH AREAS OF MVFR AND BRIEF IFR DEVELOPING IN THE LAKE ERIE LAKE EFFECT RAIN SHOWERS INITIALLY NEAR KBUF...THEN MOVING SOUTH AND EAST INTO THE SOUTHERN TIER BY TUESDAY MORNING. BY TUESDAY AFTERNOON THE LAKE EFFECT RAIN SHOWERS WILL PUSH INLAND AND TRANSITION INTO DIURNAL CONVECTION...ESPECIALLY ACROSS THE HIGHER TERRAIN OF THE SOUTHERN TIER AND FINGER LAKES. VFR CONDITIONS WILL PREVAIL...ALTHOUGH ANY HEAVIER SHOWERS MAY PRODUCE BRIEF MVFR CONDITIONS. OUTLOOK... WEDNESDAY THROUGH THURSDAY...MAINLY VFR WITH SOME LAKE EFFECT SHOWERS EAST OF LAKES ERIE AND ONTARIO PRODUCING LOCAL MVFR. FRIDAY AND SATURDAY...VFR. && .MARINE... SOUTHWESTERLY WINDS HAVE INCREASED TO 15 TO 20 KTS BEHIND THE COLD FRONT. THIS WILL CAUSE WAVES TO BUILD TO 3 TO 5 FEET ON EASTERN PORTIONS OF LAKE ERIE AND LAKE ONTARIO WITH SLIGHTLY LESSER WAVES ELSEWHERE. WINDS WILL MAINTAIN THE LONGEST ON LAKE ERIE WITH A CONVERGENCE BOUNDARY LIKELY TO ENHANCE THE SW FLOW SOUTH OF DUNKIRK TONIGHT. FOLLOWING A BRIEF DROP OFF ON TUESDAY MORNING WINDS WILL PICK UP AGAIN LATE TUESDAY SO BASED ON THIS...HAVE EXTENDED THE SMALL CRAFT ADVISORIES AS OUTLINED BELOW. COOLER CONDITIONS REMAIN IN PLACE THROUGH MID-WEEK...WITH A CHANCE FOR SOME LAKE EFFECT SHOWERS AND CONDITIONS MORE FAVORABLE FOR WATERSPOUT DEVELOPMENT. A CONVERGENCE BOUNDARY FORECAST TO DEVELOP TONIGHT ON LAKE ERIE WILL POTENTIAL PROVIDE A FOCUS FOR WATERSPOUTS TO FORM...BUT IN THIS ENVIRONMENT ANY SHOWER COULD POTENTIALLY PRODUCE A WATERSPOUT ON THE OPEN WATERS. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT TUESDAY FOR LEZ040-041. SMALL CRAFT ADVISORY UNTIL 8 PM EDT TUESDAY FOR LOZ045. SMALL CRAFT ADVISORY UNTIL 2 AM EDT TUESDAY FOR LOZ044. && $$ SYNOPSIS...APFFEL NEAR TERM...APFFEL/HITCHCOCK SHORT TERM...WCH LONG TERM...WCH AVIATION...HITCHCOCK MARINE...APFFEL  FXUS61 KBUF 091048 AFDBUF Area Forecast Discussion National Weather Service Buffalo NY 648 AM EDT Sun Apr 9 2017 .SYNOPSIS... High pressure along the east coast will move offshore through Monday and continue to provide a stretch of much needed dry weather. Temperatures will soar to well above normal from this afternoon through Monday as southwesterly breezes transport warm air into our region. Low pressure will then move through the Great Lakes Monday night and Tuesday with an associated cold front bringing the next chance of rain and possibly a few thunderstorms. && .NEAR TERM /THROUGH TONIGHT/... IR satellite imagery showing clear skies to start the day across the entire region, with high/thin cirrus poised just upstream across Southern Ontario. These high clouds will begin to move into the region this morning, but will remain thin enough to still allow for plenty of sunshine. High pressure will move off the east coast today, with developing southerly flow result in warming across the region. Subsidence under the large scale ridge will keep us dry. However a weak wave with mid- level warm advection will bring a thin layer of mid level cloud cover across the region, resulting in some filtered sunshine at times, and perhaps mostly cloudy by later this afternoon east of Lake Ontario. 850 mb temperatures really ramp up behind this surge of mid- level warm advection, with +8 to +10C at 850 mb by later this afternoon. Southerly to south-southwesterly will result in downslope flow into the lake plains, and combined with enough sunshine and mixing to 900-850 mb will support temperatures climbing rapidly through the 50s and 60s this morning. High temperatures will top out in the upper 60s to low 70s for much of the region. It will be much cooler along and northeast of Lake Erie including downtown Buffalo, and also northeast of Lake Ontario near the Jefferson County shore. The very mild airmass will remain in place tonight with continued downsloping southerly winds through the night helping to keep overnight low temperatures well above average. Locations along the lake plains in western NY will likely stay in the 50s overnight, while some of the higher terrain and north country locations will dip into the mid/upper 40s. Mid and high level clouds will slowly increase ahead of the next approach weather system. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... The warm weather is expected to continue Monday and into Tuesday. A broad area of surface high pressure will be centered just off the Mid-Atlantic coast directing a steady southwest flow across western and central New York ahead of an approaching cold front. Diurnal mixing Monday will help promote some gusty southwest winds while surface temperatures make another run into the 70s. This warmth is due to a mid level ridge of warm air over New York were 850 mb temperatures will be around +10C. The gusty southwest flow off Lake Erie and Ontario may limit the eastern lakeshores including downtown Buffalo and Watertown to the upper 60s with higher terrain locations also likely holding just shy of 70. Lingering mid-level ridging should keep dry conditions in place during the day. Monday night will run a touch milder with a decoupled southwesterly low level flow and surface dewpoints in the upper 40s to low 50s. This will keep temperatures only falling back into mid 50s overnight. Surface low pressure shifting over Michigan will push a cold front across Lake Huron and Lake Erie with a chance of some showers to the north and west of the Finger Lakes. Model consensus moves the cold front across western and central New York Tuesday morning. Frontal timing would limit surface instability, especially across western New York. Nonetheless, severe threat not out of the question given sufficient 40+ knot shear supportive of organization and dry air adequate for strong downdrafts. At this time, feel that any organized severe threat appears tied to the ability of convection to organize upstream prior to entering the area from the west. Ahead of the front, 70s will again be possible for at least the Finger Lakes with mid to upper 60s likely elsewhere. Gusty surface gradient winds will also be found through the middle of the day. The front will push east Tuesday night with any lingering showers or storms ending west to east. Cooler westerly flow behind the front will allow overnight temps to slip into the low to mid 40s. High temperature records at BUF/ROC/ART should not be challenged from this period of warmth but new High Low records could be possible Monday night ahead of the front. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... In the wake of Tuesday's cold front...high pressure and cooler/drier will build across the region Wednesday. This will translate into a return to fair and dry weather for our region...with highs on Wednesday mostly ranging through the 50s...except along the eastern shores of the lakes where an onshore flow will restrict temperatures to the 40s. Moving on into the latter portions of next week...the 12Z/08 medium range guidance suite continues to trend faster with the next mid level trough and attendant surface low. With the GFS remaining a fast (and somewhat weaker) outlier...have continued to lean toward a GEM/ECMWF consensus for this package...which suggests shower chances arriving later Thursday and then peaking Thursday evening...before winding down the remainder of Thursday night and early Friday. With the continuation of the overall faster trend to this system...Friday itself now looks to be mainly dry as strong surface-based ridging and drier air builds into the region in its wake...with the return to quiet weather then likely to persist through Friday night and Saturday as the high first crests across New York State...then drifts to the Atlantic coastline. Otherwise temperatures should continue to average out a bit above normal...with daytime highs generally ranging through the 50s...and nightly lows mostly running in the 30s. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... VFR conditions will dominate today and tonight as high pressure remains in control. A mid level deck around 10kft will move east across Lake Ontario to the eastern Lake Ontario region during the afternoon in association with a mid level warm front, otherwise the rest of the area will just see a modest increase in high/thin cirrus level cloudiness today. Winds will remain fairly light, although lake breeze development near KBUF/KIAG could allow for a gusty southwest breeze gusting to around 20 kts this afternoon. Periods of mid/high clouds will cross the region tonight with VFR continuing. Low level wind shear will develop as a 40-50 knot low level jet crosses the region. Outlook... Monday...Mainly VFR. Tuesday...Mainly VFR with a chance of showers and thunderstorms. Wednesday...VFR. Thursday...VFR/MVFR with a chance of showers. && .MARINE... A ridge of high pressure will drift off the east coast today, keeping fairly light winds in place today. Southwest winds will increase on Monday, but conditions should remain below Small Craft Advisory levels with stronger winds likely to impact land areas. A cold front will cross the area Tuesday with somewhat stronger southwest winds, and possibly a few thunderstorms as well. && .HYDROLOGY... There are a few flood warnings still in effect this morning. For more details, see the latest FLW and FLS products. The Black River at Watertown has leveled off near its likely crest overnight in minor flood stage, before slowly falling through today. There will continue to be minor flooding near the river and in agricultural lands in central Jefferson and north central Lewis counties. There is also flooding along the Seneca River and in Cross Lake in Cayuga County. Water levels seem to have leveled off overnight on the Seneca River at the Port Byron gauge. However this is a very slow responding river and could take some time before receding, with high flows likely continuing for a few more days. Water flows in the Seneca River are highly complex and difficult to forecast given the numerous inflows from the Finger Lakes and extensive control structures along the Erie Canal. Water levels will continue to run very high along the Oswego River over the next few days. It appears levels will remain just below 11 feet, which is the level where minor flooding begins along portions of the river, including the riverwalk in the City of Oswego. Flows on the Oswego River are also highly complex and difficult to forecast given the numerous inflows from the Finger Lakes, Oneida Lake, and extensive control structures along the Erie Canal. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...None. MARINE...None. && $$ SYNOPSIS...CHURCH/HITCHCOCK NEAR TERM...CHURCH/HITCHCOCK SHORT TERM...TMA LONG TERM...JJR AVIATION...CHURCH/HITCHCOCK MARINE...CHURCH/HITCHCOCK HYDROLOGY...HITCHCOCK