FXUS61 KLWX 041010 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 610 AM EDT Tue Oct 4 2016 .SYNOPSIS... High pressure will build southward into the region through early Friday. Hurricane Matthew may track along or offshore the southeast U.S. and mid-Atlantic coasts over the weekend. && .NEAR TERM /THROUGH WEDNESDAY/... Dense fog advisory issued for western MD and the Shenandoah valley in eastern WV. Obs and an AVHRR pass at 0856 UTC show widespread fog now with 0SM at some locations. A few clouds are evident across the area early this morning while patchy dense fog is being reported at Luray. Sfc dewpoints are significantly lower attm than 24 hrs ago. As a result, widespread dense fog is not anticipated attm but will continue to monitor. High pressure will build swd into the region from northern New England today. Sfc flow becomes onshore later today with low clouds expected to move in from the east during the day. A few showers can't be ruled out over the Chesapeake Bay and adjacent MD counties. Marine layer deepens tonight with bkn-ovc low clouds expected. Patchy light drizzle will be possible along the Appalachians and Blue Ridge mtns where model soundings show a saturated layer from sfc up to 850 mb. Low cigs Wed morning will be slow to lift out Wed beneath a strong subsidence inversion. && .SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/... Partial clearing takes place early Wed evening with model soundings showing potential for dense fog. Fog dissipates Thu yielding a nice autumn day under high pressure. Fair weather expected Thu night. Attm, model soundings do not show potential for fog. && .LONG TERM /FRIDAY THROUGH MONDAY/... High pressure across the Mid-Atlantic region will be retreating to New England Friday- Friday night as Hurricane Matthew moves north of the Bahamas. Over the past 24 hours there has been a westward shift in the forecast track for Hurricane Matthew. This brings Matthew closer to the FL/SC/NC coastline Thursday-Saturday. An upper level trough will move across the Great Lakes this weekend. The speed and amplitude of the trough will play a major role in the track of Matthew as it moves towards the Mid-Atlantic region. Details of tropical storm or hurricane impacts from Matthew are unknown at this time across the Mid-Atlantic region. The cloud shield from Matthew will result in dense cloud cover across the region this weekend. Easterly flow is also expected across the Mid-Atlantic region this weekend. Please consult the National Hurricane Center for the most up to date forecasts regarding Hurricane Matthew. && .AVIATION /10Z TUESDAY THROUGH SATURDAY/... Mainly VFR early this morning except at KMRB where IFR vsbys are being reported. Onshore flow today will result in bkn/ovc 030-040 cigs. MVFR/IFR cigs likely tonight then are slow to lift Wed. Better fog potential Wed night. VFR conditions Thu. Flight restrictions possible this weekend as onshore flow persists. Will have to watch Matthew for potential impacts to the terminals this weekend. && .MARINE... Winds expected to strengthen later today with SCA conditions likely persisting into early next week. Will be adjusting SCA into Wed. A Small Craft Advisory may be needed for portions of the waters late this week. Will have to watch Matthew for potential impacts to the waters this weekend. Refer to the National Hurricane Center for the latest on Matthew. && .TIDES/COASTAL FLOODING... Tidal anomalies will increase Tuesday through the end of the week due to a developing onshore flow. Minor flooding is likely during this time. Will also have to watch the track of Matthew because that has the potential to add to the flood threat this weekend. Please refer to the National Hurricane Center for the latest information on Matthew. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...Dense Fog Advisory until 9 AM EDT this morning for MDZ003-502. VA...Dense Fog Advisory until 9 AM EDT this morning for VAZ027>031. WV...Dense Fog Advisory until 9 AM EDT this morning for WVZ050>053- 055-502-504. MARINE...Small Craft Advisory from 2 PM this afternoon to 11 AM EDT Wednesday for ANZ530>532-538>540. Small Craft Advisory from 2 PM this afternoon to 6 PM EDT Wednesday for ANZ533-534-537-541>543. && $$ SYNOPSIS...LFR NEAR TERM...LFR SHORT TERM...LFR LONG TERM...HSK AVIATION...HSK/LFR MARINE...HSK/LFR TIDES/COASTAL FLOODING...LFR