Area Forecast Discussion
Issued by NWS Sterling, VA

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
919 FXUS61 KLWX 211908 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 308 PM EDT TUE JUN 21 2016 .SYNOPSIS...
-- Changed Discussion --
A cold front will cross the region this evening. High pressure will briefly build in from Canada on Wednesday. A warm front will lift north across the region Wednesday night. Another cold front will cross the region later Thursday and Thursday night. High pressure will build back across the area for the weekend.
-- End Changed Discussion --
&& .NEAR TERM /THROUGH WEDNESDAY/...
-- Changed Discussion --
Very active afternoon with plenty of showers and thunderstorms. Severe Thunderstorm Watch is in effect until 9PM but will probably be able to start shaving off portions of it as it becomes more clear where the first line has stabilized the atmosphere. Patchy fog possible overnight. Otherwise...high pressure from Canada will usher in drier air for the region on Wednesday. Temperatures will drop a bit but northwesterly downslope flow likely to prevent a big drop.
-- End Changed Discussion --
&& .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
-- Changed Discussion --
Front that moves through as a cold front tonight will push back north as a warm front on Wednesday night with rain and perhaps embedded thunder moving back across the region. Very warm and humid air mass moves in behind warm front for Thursday and we will have another potential round of severe weather later Thursday into Thursday evening. As front drops back south on Thursday night the showers and thunderstorms will move southeast away from the area. An upper trough of low pressure will swing across the region Friday. There is a chance for a lingering shower or thunderstorm, mainly across the west and south.
-- End Changed Discussion --
&& .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
-- Changed Discussion --
High pressure will build into the region Friday night through Sunday. Drier and cooler air will follow throughout the weekend. This same area of high pressure will move offshore and closer to southern New England Sunday night and Monday. A warm and more humid return flow will evolve Sunday night through Tuesday. This will help in fueling showers and thunderstorms each period. A few thunderstorms could contain gusty winds.
-- End Changed Discussion --
&& .AVIATION /19Z TUESDAY THROUGH SUNDAY/...
-- Changed Discussion --
Brief IFR with severe thunderstorms across the region at present. Hail and damaging winds main threat. This threat will rapidly diminish this evening as cold front sinks south with VFR later tonight thru Wednesday. Front moves back in as a warm front with more rain later Wednesday night into early Thursday. Another round of severe weather possible later Thursday into Thursday night. Ifr conditions possible near CHO with any showers or thunderstorms Friday. Vfr conditions all terminals Friday night. Winds northeast around 5 knots Friday becoming southeast around 5 knots Friday night.
-- End Changed Discussion --
&& .MARINE...
-- Changed Discussion --
Marginal SCA continues at present. Also have damaging thunderstorms with wind and hail moving across the waters thru early this evening. Conditions improve later tonight and continue dry thru Wednesday, though winds may be near SCA limits on Wednesday. Warm front moves in with more rain later Wednesday night then SCA looking likely ahead of next cold front on Thursday into Thursday night, along with another round of t-storms. No marine hazards expected Friday and Friday night.
-- End Changed Discussion --
&& .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...None. VA...None. WV...None. MARINE...Small Craft Advisory until 8 PM EDT this evening for ANZ530>543. && $$ SYNOPSIS...RCM NEAR TERM...RCM SHORT TERM...RCM LONG TERM...KLW AVIATION...RCM/KLW MARINE...RCM/KLW

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.