FXUS63 KABR 121739 AAC AFDABR AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE ABERDEEN SD 1239 PM CDT FRI JUN 12 2015 .UPDATE... ISSUED AT 1100 AM CDT FRI JUN 12 2015 NO CHANGES TO THE FORECAST AT THIS TIME. && .SHORT TERM...(TODAY THROUGH SUNDAY AFTERNOON) ISSUED AT 335 AM CDT FRI JUN 12 2015 TIMING OF A SLOW MOVING FRONTAL BOUNDARY WILL BE THE MAIN FORECAST CONCERN. TODAY WILL FEATURE SEASONAL TEMPERATURES ALONG WITH DRY CONDITIONS THANKS TO WEAK UPPER LEVEL RIDGING. THE RIDGE WILL SHIFT EAST ON SATURDAY AS A BROAD UPPER LEVEL TROUGH CURRENTLY OVER THE PAC NW TRANSLATES EASTWARD. THIS TROUGH...ALONG WITH A SURFACE COLD FRONT WILL BE SLOW TO CROSS THE REGION THROUGH THE WEEKEND WITH SHOWERS AND THUNDERSTORMS POSSIBLE SATURDAY AFTERNOON THROUGH SUNDAY. CAPE VALUES CLIMB ABOVE 1500 K/JG ALONG THE FRONT ON SATURDAY AFTERNOON WHICH WOULD SUPPORT SOME STRONGER STORMS. HOWEVER 0-6 KM BULK SHEAR VALUES ARE FAIRLY WEAK...OR ABOUT 20 KNOTS...AND THERE IS LITTLE UPPER LEVEL FORCING AS WELL. ANY STRONG STORMS SHOULD BE REGULATED TO NORTH DAKOTA...OR CLOSER TO THE SURFACE LOW PRESSURE. SHOWERS AND PERHAPS A FEW THUNDERSTORMS WILL CONTINUE ON SUNDAY THANKS TO AN UPPER LEVEL SHORTWAVE. CONDITIONS MAY BEGIN DRYING OUT DURING THE LATE AFTERNOON HOURS AS A SURFACE HIGH PRESSURE BUILDS INTO THE REGION. .LONG TERM...(SUNDAY EVENING THROUGH THURSDAY) ISSUED AT 335 AM CDT FRI JUN 12 2015 THE LONG TERM MODELS REMAIN IN FAIR AGREEMENT THROUGH THE FORECAST. GENERALLY FLAT MID LEVEL FLOW IS EXPECTED DURING THE PERIOD. IT DOES APPEAR THAT THE BEST CHC FOR WIDESPREAD PCPN WILL BE LATE TUESDAY AND TUESDAY NIGHT. ALL MODELS INDICATE A DECENT WAVE BOTH SFC/ALOFT MOVING OVER THE REGION. ALTHOUGH THAT SAID THE ECMWF IS FURTHER NORTH VS GFS/GEM WITH HIGHEST QPF AMOUNTS. THE GFS DOES APPEAR TO SUFFER A LITTLE FROM LATENT HEAT FEEDBACK. LATE IN THE PERIOD A SFC BOUNDARY SETTLES OUT JUST SOUTH OF THE ABR CWA...THUS KEEPING US CLOSE TO ANY CONVECTIVE ACTIVITY THAT MAY FORM NEAR THIS BAROCLINIC ZONE. TEMPERATURES OVERALL SHOULD BE NEAR OR JUST SLIGHTLY UNDER CLIMO NORMS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1235 PM CDT FRI JUN 12 2015 CONDITIONS ARE CURRENTLY VFR AND SHOULD REMAIN SO FOR THE NEXT 24 HOURS AT ALL TERMINALS EXCEPT KATY. AFTER 06Z...IFR PROBABILITIES START INCREASING AT KATY...AS SOUTHERLY LOW LEVEL FLOW WILL DRAW HIGHER AMOUNTS OF SURFACE/NEAR SURFACE MOISTURE AND LOW CLOUDS NORTHWARD ONTO THE PRAIRIE COTEAU OVER NORTHEAST SOUTH DAKOTA. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ UPDATE...CONNELLY SHORT TERM...SD LONG TERM...TDK AVIATION...DORN  FXUS63 KABR 220924 AFDABR AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE ABERDEEN SD 424 AM CDT TUE SEP 22 2015 .SHORT TERM...(TODAY THROUGH THURSDAY AFTERNOON) ISSUED AT 424 AM CDT TUE SEP 22 2015 UPPER PATTERN FEATURES ZONAL FLOW ALONG THE CANADIAN BORDER...RESULTING IN HIGH PRESSURE MOVING TO OUR NORTH. THIS COOL/DRY AIRMASS WILL LAST FOR MUCH OF THE DAY...HOWEVER WE WILL SEE A WAVE OPEN AND LIFT NORTHWARDS OUT OF THE DESERT SOUTHWEST...BRINGING A PLUME OF TROPICAL MOISTURE INTO THE REGION. BEST FORCING WILL BE THIS EVENING AND OVERNIGHT AS A 30-40KT LOW LEVEL JET SETS UP OVER NEBRASKA/SOUTHERN SOUTH DAKOTA. PROFILES SUPPORT AROUND 1000-1500J/KG MUCAPE AND SOME DIRECTIONAL SHEAR BUT WINDS ALOFT ARE NOT PARTICULARLY STRONG. WITH MAINLY SKINNY CAPE BASED OFF LOW LEVEL WARM ADVECTION EVIDENT IN PROFILES TONIGHT...THE THREAT MAY NOT BE SO MUCH SEVERE STORMS AS IT WILL BE FOR HEAVY RAIN. SLOW STORM MOTION...PWATS AROUND 3 STANDARD DEVIATIONS ABOVE CLIMO...AND WARM CLOUD DEPTH WILL ALL AID IN PRECIPITATION EFFICIENCY. THE SREF PROBABILITIES FOR EXCEEDING 1/2 AND 1 INCH ARE BETWEEN 40 AND 20 PERCENT RESPECTIVELY...THOUGH THE SREF BULLSEYE FAVORS WESTERN MINNESOTA. POOR MODEL PERFORMANCE TYPICAL WITH THESE MAINLY QUASI-BAROTROPIC SYSTEMS HAS RESULTED IN TIMING DIFFERENCES BETWEEN THE GFS/NAM AND SEVERAL CAMS LEADING TO POOR FORECASTER CONFIDENCE. AS THE UPPER WAVE LINGERS OVERHEAD...WITH ANOTHER FAVORABLE LOW LEVEL JET SET UP FOR WEDNESDAY NIGHT...ANTICIPATE ANOTHER ROUND OF CONVECTION. THE FOCUS SHIFTS INTO WESTERN MINNESOTA EARLY ACCORDING TO THE GFS...HOWEVER IF THE SLOWER NAM VERIFIES...WE WILL SEE MORE WIDESPREAD PRECIPITATION EAST OF THE MISSOURI RIVER WEDNESDAY NIGHT. .LONG TERM...(THURSDAY EVENING THROUGH MONDAY) ISSUED AT 424 AM CDT TUE SEP 22 2015 THE MODELS SHOW GOOD AGREEMENT EARLY ON AND THEN DIVERGE LATER ON WITH THE UPPER LEVEL AND SURFACE FEATURES. UPPER LEVEL RIDGING OVER OUR REGION WILL SLOWLY BUILD EAST THROUGH THE LONG TERM WHILE TROUGHING OFF THE PACIFIC COAST SLOWLY MOVES IN. THE LARGE TROUGH OFF THE WEST COAST SENDS OFF ITS NORTHERN PORTION ACROSS SOUTHERN CANADA/NORTHERN US FROM SATURDAY NIGHT INTO MONDAY. THE EC WAS QUICKER THAN THE GFS WITH THIS TROUGH. AT THE SURFACE...HIGH PRESSURE RIDGING ON FRIDAY OVER THE CWA WILL BUILD EAST WITH WINDS TURNING SOUTHWEST AND INCREASING INTO SATURDAY. THUS...EXPECT SUNNY SKIES FOR BOTH FRIDAY AND SATURDAY WITH A WARM UP. SATURDAY WILL ALSO BE BREEZY/WINDY ACROSS THE CWA WITH A TIGHT SURFACE PRESSURE GRADIENT ALONG WITH STRONG LOW LEVEL MIXING WINDS. THE MODELS THEN SHOW A COOL FRONT PUSHING ACROSS THE REGION SUNDAY AND SUNDAY NIGHT. THE EC MODEL SHOWS STRONGER SURFACE HIGH PRESSURE BUILDING IN BEHIND THIS FRONT FOR MONDAY THAN THE GFS. HIGHS THROUGH THE PERIOD SHOULD REMAIN ABOVE NORMAL WITH HIGHS MAINLY IN THE 70S AND LOWER 80S WITH SOME MID 80S OUT WEST ON SATURDAY. THE PERIOD ALSO LOOKS TO BE DRY UNTIL MAYBE LATE WITH SOME SLIGHT CHANCES BEING INTRODUCED. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1224 AM CDT TUE SEP 22 2015 VFR CONDITIONS ARE EXPECTED FOR ALL LOCATIONS THROUGH TONIGHT AND TUESDAY. MID AND HIGH LEVEL CLOUDS WILL INCREASE OVER THE REGION AS LIFT FROM AN UPPER LEVEL LOW PRESSURE SYSTEM MOVES IN. ALSO...EXPECT SOME SHOWERS TO DEVELOP DURING THE EVENING HOURS TUESDAY. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ SHORT TERM...CONNELLY LONG TERM...MOHR AVIATION...MOHR  FXUS63 KABR 270907 AFDABR Area Forecast Discussion National Weather Service Aberdeen SD 307 AM CST Sun Nov 27 2016 .SHORT TERM...(Today through Tuesday Afternoon) Issued at 307 AM CST Sun Nov 27 2016 Two main items of concern for the forecast, the dense fog in the very near term and then the strong, potentially record breaking low for KABR, for tonight into early next week. First for the fog, this fog has been persistent over central MN and steadily shifted west into far northeast South Dakota this past evening. Have seen widespread 1/4mi visibility with the fog and the going dense fog looks to be in good shape for that area. GOES FLS IFR probs have a good handle on the westward extent in the current dense fog advisory and are hinting at some fog farther to the west. That shallow/patchy dense fog has been seen at times in Brown and farther southeast towards Clark/Hamlin counties. While webcams are sparse, not seeing too much for thick fog, so will continue to go with the SPS through 8am for the patchy fog. The main question is how long the fog will last. high resolution models show this fog sticking around through much of the morning for the far northeastern CWA before visibilities gradually lift into the afternoon (similar to yesterday in central MN). After discussion with surrounding offices, will hold on to current dense fog end time and monitor through the morning hours for extension. While temps remain in the 20s...do think there is the potential for light icing and slick spots on roads and will continue that mention in the statements. Outside of the fog, expect some high clouds to start the day before thicker clouds quickly move in during the late morning and afternoon associated with the low that will move into the area. This low will rapidly develop and move northeast today as a strong shortwave and pv anomaly (currently over the four corners region) moves into the region. Models are continuing to show an upper 970s low over far northeast SD by 12z Monday, which should produce a new November SLP record at KABR. Plenty of lift present with the shortwave and low, so expect rain to quickly move into the area late this afternoon and into the early evening hours. Behind the initial surge of precipitation, models are indicating a dry slot to slide just to the SE of the CWA but most of the CWA will be experiencing lighter precipitation associated with the surface and mid level low over the area, thus held on to higher end PoPs. The biggest uncertainty is the amount and location of precipitation on the back side of the low associated with the nose of the TROWAL. The location will be key, as colder air will be working into the area as that precipitation occurs and changing it over to snow. GFS/ECMWF are fairly consistent with surface/upper low track and have similar thermal fields, while the NAM is a little farther to the west and colder. Will trend towards the GFS/ECMWF idea for the tonight through Tuesday period. That will hold off the change over to snow over the far west until late evening and shortly after midnight towards KMBG. Expect that transition to continue eastward through the night, reaching the James River valley around 12z. Will continue Thunder mention with weak MUCAPE values and marginal 700-500mb lapse rates and showalter values. The low will slowly wobble and weaken around the SD/ND/MN border through Monday night before beginning to slide to the southeast across MN on Tuesday. With that location and abundant moisture in place, expect fairly steady light precipitation to be ongoing through much of the Mon-Tue period. While precip will start as snow aloft, there may be enough low level warming to mix the snow with or change it over to rain at times, especially over the southern and eastern portions of the CWA Monday afternoon. Do wonder if models are overdoing surface temps a touch and with wetbulb0 heights only above 700ft from the Coteau and eastward could see p-type being more snow than the forecast currently indicates for Monday afternoon. Will need to watch over the next couple of shifts. While the precip and snow will be persistent, not expecting too much of an impact or significant accumulations (generally an inch or two every 12 hours). In addition, with temperatures rising to around or just above freezing during the day on Monday/Tuesday, that should help keep the roads more on the wet side outside any of the stronger periods of snow. Finally, there will be breezy NW winds developing Mon afternoon and continuing into Tuesday. Going consensus looks pretty good with gusts to 30kts towards KMBG. With warm temps and generally more of a wet snow, don't expect too much blowing snow through Tuesday, although there could be some light drifting snow over the northwest CWA at night when temps cool slightly. That idea is supported by the Baggaley blowing snow model which struggles to give probabilities of blowing snow exceeding 20% on Tuesday when snow is occurring. .LONG TERM...(Tuesday Evening through Saturday) Issued at 307 AM CST Sun Nov 27 2016 A large upper level trough will be over much of the country when the extended period begins, with the main low center spinning over Minnesota. The amplitude of the trough begins to get dampened by mid week, with a brief return to ridging Friday and Friday night before another shortwave approaches Saturday. At the surface, a strong low pressure system will be centered over Minnesota Tuesday night, then remains there before drifting off toward the Great Lakes Wednesday night. Will still see decent chances of precipitation Tuesday night and Wednesday, with light snow likely lingering into Thursday night as well. Snow accumulations Tuesday night into Wednesday may be an additional 1 to 3 inches. The remainder of the period looks dry at this time as high pressure slides across the region Friday and Saturday. Daytime highs will be in the upper 20s to mid 30s through the period, with overnight lows in the upper teens to mid 20s. && .AVIATION...(For the 06Z TAFS through 06Z Sunday Night) Issued at 1137 PM CST Sat Nov 26 2016 Dense LIFR fog has spread over much of Minnesota and far northeast South Dakota and continues to very slowly move west. While a more shallow IFR fog extends from KATY to KABR. Expect IFR visibilities to continue through the night at KABR and KATY...perhaps dropping to LIFR at times. Conditions should gradually improve after 15Z Sunday. There will be a break where VFR conditions return Sunday afternoon. However, a low pressure system will move into the region later in the day Sunday. This system will initially bring rain to the region, with lowering ceilings and reduced visibility likely late in the TAF period. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...Dense Fog Advisory until 9 AM CST this morning for SDZ008-021. MN...Dense Fog Advisory until 9 AM CST this morning for MNZ039-046. && $$ SHORT TERM...SRF LONG TERM...Parkin AVIATION...Serr