Area Forecast Discussion
Issued by NWS Sterling, VA

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000 FXUS61 KLWX 291403 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 1003 AM EDT Mon Aug 29 2016 .SYNOPSIS...
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High pressure will remain over the Mid Atlantic today before moving offshore. A cold front will move through the area Wednesday night. High pressure returns for late in the week.
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&& .NEAR TERM /THROUGH TONIGHT/...
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High pressure centered to the northeast extending back across the DELMARVA region, sandwiched between a weak frontal boundary off the Carolina coast and an approaching cold front currently progged over central PA up into New England. This will keep dry yet warm conditions in place heading into the afternoon hours. By this afternoon, increasing instability with diurnal heating. Models are pegging the aforementioned cold front to weaken/dissipate generally south of the Mason-Dixon, while holding a bit more composure to the north. However, cannot rule out a stray shower/thunderstorm late this afternoon right along the PA/MD border. Over the western area of the CWA, terrain with the increased instability will aid in producing scattered showers and thunderstorms. Loss of heating tonight will lead to decreasing coverage of showers and thunderstorms. Dry weather the second half of the night.
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&& .SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
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Warmth will continue Tuesday with highs in the upper 80s/90. Again there could be a chance for afternoon convection...primarily over the mountains. Upper wind field will be weak which will keep severe chances low. Convection chances will drop off overnight leaving the final night of August with lows in the mid 60s...except warmer in the normal locations.
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&& .LONG TERM /WEDNESDAY THROUGH SUNDAY/...
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Cold front will be approaching from the northwest late Wednesday. Out ahead of the front will see another hot day with temperatures up around the 90 degree mark. Instability expected to be relatively limited with dew points holding in the 60s and presence of warm mid level air. However should still be enough to initiate some showers/thunderstorms in the higher terrain and along the front as it propagates eastward Wednesday evening and Wednesday night. Upper trough and associated energy will move overhead on Thursday, which will keep the chances for showers and a couple of thunderstorms around. But with cooler air behind the front and presence of cloud cover, instability should once again remain fairly limited. Highs mainly in the 80s. Will continue to monitor tropical activity in the Gulf of Mexico for late in the week but upper trough overhead and surface high gradually building towards and into the region are currently expected to suppress any system to the south and east. Please refer to the NHC products for official tropical forecasts. May see a lingering isolated shower/storm Friday with upper trough overhead, with dry weather currently forecast for the weekend. Highs in the 70s/80s Friday and over the weekend. Lows drop off into the 50s/60s.
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&& .AVIATION /14Z MONDAY THROUGH FRIDAY/... VFR conditions expected today through Tuesday. Thunderstorm development possible over the mountains both days but probability of storms being near airports is low. Predominantly VFR expected Wednesday through Friday. Only restrictions would come in some patchy fog at night/early morning and any scattered showers/thunderstorms late Wednesday and Thursday. && .MARINE... Winds expected to remain below SCA values today through Tuesday. Cold frontal system will cross the waters Wednesday night and into Thursday with potential for some scattered showers and thunderstorms. Small Craft Advisory may be needed Thursday night and Friday with increasing northerly winds behind front. && .CLIMATE... Ranking of summer 2016 in terms of average temperature (JUN 1 - AUG 28) Site Rank Average Temperature DC 3 80.5 Balt 15* 77.3 IAD 3 77.3 * tied with 1937, 1994, and 2002 && .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...None. VA...None. WV...None. MARINE...None. && $$ Update...SEARS Previous Discussion...Woody!/MJM

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