Area Forecast Discussion
Issued by NWS Sterling, VA

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000 FXUS61 KLWX 291945 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 245 PM EST Tue Nov 29 2016 .SYNOPSIS...An area of low pressure will move across the area Wednesday with a cold frontal passage Wednesday night. High pressure will return to the region Friday and Saturday. Low pressure will approach the region Sunday. && .NEAR TERM /THROUGH TONIGHT/...Showers will end soon over southern MD with widespread low clouds and dense fog developing tonight as pressure gradient weakens and ground remains wet. A dense fog advzy may be needed later tonight. Showers begin to move in again into western areas by 09Z and spread northeastward during the morning hours as heights begin to fall as upper low over the upper midwest moves across the western Great Lks. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...Showers spread northeast across the northern half Wed morning while southern areas remain mostly dry but cloudy. Model soundings indicate sufficient elevated instability and high equilibrium temperatures during the morning hours suggesting there could be a few rumbles of thunder early in the day. Cold frontal bdry begins to enter western areas around 21Z with a narrow line of showers moving from Higland county east to southern MD during the late afternoon and early evening hours. Cdfnt clears the fcst area by 03Z Thu with showers ending. A half to an inch of rain is expected. Drying and turning colder on Thu under NW flow. && .LONG TERM /FRIDAY THROUGH TUESDAY/... High pressure centered to our southwest will keep dry conditions Friday into Saturday... it will then move overhead into early Sunday. High temperatures will be in the 40s and 50s in most place, could reach the low 30s at higher elevations. Sunday into Monday guidance diverges in the timing of a low pressure/upper level short wave that will move from the Gulf states to the northeast sometime between Sunday afternoon and Monday night. Precipitation associated to this system could be approaching the Mid- Atlantic region as early as Sunday evening -based on the Euro. Warm front moves through followed by a cold front. High pressure/dry conditions for Tuesday. GFS has a similar scenario but happening almost 24 hours later... with drier conditions Monday. Low temperatures Sunday and Monday nights could allow for some snow showers, mainly at higher elevations. && .AVIATION /19Z TUESDAY THROUGH SUNDAY/...LIFR/VLIFR conditions tonight under light winds. Cigs and vsbys improve somewhat tomorrow but remain mostly IFR through most of the day. Two rounds of showers are expected one in the morning and then in the late afternoon and evening. Cdfnt crosses the area by 06Z Thu with shifting winds and showers ending improving flying conditions. Dry conditions expected for Friday into part of Sunday with high pressure dominating weather conditions... there VFR conditions expected. On Sunday possible storm system could bring showers to the terminals, allowing for conditions to become sub-VFR... but there is still uncertainty on the timing of this system. && .MARINE...Will cancel gale warning as gale force winds never materialized. Gusty winds again tomorrow with gale force winds possible mainly during the evening with gusty showers. Dry conditions expected for Friday into part of Sunday with high pressure dominating weather conditions. Gusty winds possible Friday into Sunday... so a small craft advisory could be possible during this period. && .TIDES/COASTAL FLOODING...Coastal flood advzy issued for southeast Harford, southeast Baltimore and Anne Arundel counties where anomalies of 1.5 to 2.0 feet expected. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...Coastal Flood Advisory from 8 PM this evening to 1 AM EST Wednesday for MDZ508. Coastal Flood Advisory until 9 PM EST this evening for MDZ014. Coastal Flood Advisory from 5 PM this afternoon to 10 PM EST this evening for MDZ011. VA...None. WV...None. MARINE...Small Craft Advisory until 6 PM EST Wednesday for ANZ531-536- 539. Small Craft Advisory until 6 PM EST this evening for ANZ530- 535-538. Small Craft Advisory from 6 AM to 6 PM EST Wednesday for ANZ530-535-538. Small Craft Advisory from 6 PM this evening to 6 PM EST Wednesday for ANZ532>534-537-540>543. && $$ SYNOPSIS...LFR NEAR TERM...LFR SHORT TERM...LFR LONG TERM...IMR AVIATION...IMR/LFR MARINE...IMR/LFR TIDES/COASTAL FLOODING...LFR

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