Area Forecast Discussion
Issued by NWS Sterling, VA

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000 FXUS61 KLWX 152004 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 304 PM EST Thu Feb 15 2018 .SYNOPSIS...
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A cold front will cross the area early on Friday. High pressure will build north of the area Friday night. Low pressure will then pass to the south Saturday night. High pressure will return for early next week before another frontal system affects the area mid next week.
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&& .NEAR TERM /THROUGH TONIGHT/...
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Deep moisture with PWs 1-1.25 inches will continue to advect ewd from the OH valley into our area tonight with showers expected to develop ahead/along an approaching sharp cold front. Rainfall amounts will range between 0.25 inches in the southeast to one inch in the far NW corner. The front will become fairly progressive which should limit rainfall totals. No flooding is anticipated anywhere. Cdfnt will cross the area around 09Z and push south of the area by 15Z.
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&& .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
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Showers will end gradually from north to south on Fri with gusty NW winds drying out things rapidly. Temps will begin to fall rapidly after 10AM from the upper 50s in the morning to the upper 40s by sunset. Cold Fri night under building high pressure to the north. Moisture will then begin to spread northeastward Sat morning as coastal low develops offshore the mid-Atlc coast. Snow is expected at onset late Sat morning in the southwest but with a quick transition to snow/sleet mix late Sat and Sat evening. This is a very quick moving system with precip duration only about 6 hrs. No freezing rain is anticipated due to sfc temps generally abv freezing. Snow to liquid ratios will be generally around 5 to 1 or less in where sleet mixes in and between 7 to 10 along the Mason Dixon line where precip remains as snow through the event. Snow amts of an inch or less are expected south of I-70 with 1-2 inches north of there and nothing south of I-64. Precip ends by midnight Sat night.
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&& .LONG TERM /SUNDAY THROUGH THURSDAY/...
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High pressure builds overhead on Sunday bringing dry conditions over our region into Sunday night as southerly flow settles in. A low pressure system moving towards the Great Lakes will push a warm front over or nearby on Monday that could bring unsettled weather over our area. A cold front will then stall to our northwest Tuesday into Wednesday and keeping southerly flow over us. Depending on how close it stalls, we could experience some precipitation. The front will then slowly move across on Thursday keeping the chance of precip over our CWA. A warming trend will be in place in the long term period as high temperatures will be gradually increasing from the 40s and 50s on Sunday into near the 70s Tuesday and Wednesday. High temperatures will drop around 10 degrees on Thursday due to the front.
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&& .AVIATION /19Z THURSDAY THROUGH TUESDAY/...
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Showers expected tonight as cdfnt crosses the area with brief cigs restrictions into MVFR category. Wind shift expected around 09Z with gusts around 20 kt expected. Snow expected late Sat at onset with a quick transition to snow/sleet mix Sat evening with precip ending by midnight Sat night. Flight restrictions are likely late Sat and Sat evening. VFR conditions are expected during on Sunday as high pressure builds overhead. Periods of sub-VFR conditions possible Monday into Tuesday as frontal boundaries affect our area, but it will depend on how close they move.
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&& .MARINE...
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Winds expected to strengthen late tonight into Fri with SCA conditions expected. Winds should drop off below SCA Sat and remain so through early next week. Winds are expected to remain below SCA criteria from Sunday into Monday night, therefore no small craft advisory expected these days. Winds will increase later on Tuesday, which will be monitored in case a SCA is required.
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&& .LWX WATCHES/WARNINGS/ADVISORIES...
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DC...None. MD...None. VA...None. WV...None. MARINE...Small Craft Advisory until 7 PM EST Friday for ANZ530>543.
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&& $$ SYNOPSIS...LFR NEAR TERM...LFR SHORT TERM...LFR LONG TERM...IMR AVIATION...IMR/LFR MARINE...IMR/LFR

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