Area Forecast Discussion
Issued by NWS Sterling, VA

Current Version | Previous Version | Graphics & Text | 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
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
419 FXUS61 KLWX 210131 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 931 PM EDT Tue Jun 20 2017 .SYNOPSIS...
-- Changed Discussion --
High pressure will be perched west of the area through Thursday. A cold front will cross the area Friday into Saturday, with tropical moisture streaming into the Mid Atlantic.
-- End Changed Discussion --
&& .NEAR TERM /THROUGH WEDNESDAY/...
-- Changed Discussion --
Had to keep an eye on showers that popped up near Baltimore that produced some brief heavy downpours but these weakened with sunset. Summer solstice occurs at 12:24 am. Drier air slowly infiltrating the forecast area. Broad, diffuse high pressure will remain west of the area through the night. Dewpoints now in the 50s areawide, which should make for a comfortable evening. Some mid level clouds likely will preclude optimal cooling. Lows ranging from the mid 50s far west to near 70 along the Bay.
-- End Changed Discussion --
&& .SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/... Weather will be benign for the next couple of days. A shortwave crossing from the Great Lakes to the northeast Wednesday could provide a little moisture. Have limited chance PoPs (mostly showers, perhaps a rumble of thunder) to northern Maryland and the Potomac Highlands. The lingering baroclinic zone from yesterdays cold front could also yield a thunderstorm to the tip of southern Maryland. Thursday we will be in the subsidence in the wake of the trough axis. Temperatures at 850 mb do rise slightly, so will bump high temps up to near 90. Dewpoints increase a pinch as well, into the 60s. Eyes will then turn to the Gulf of Mexico to see what the pace of that precip will be. Given the range of possibilities will take a tempered approach...20-30 PoP after midnight. && .LONG TERM /FRIDAY THROUGH TUESDAY/... Moisture and perhaps circulation from the remnants of Tropical Storm Cindy look to be drawn toward the Mid-Atlantic ahead of a cold front that is expected to cross the area Friday night into Saturday. This could produce enhanced rainfall Friday until the cold frontal passage over the Mid-Atlantic. Once the cold front passes, 12Z GFS/ECMWF suggest weak surface high pressure over the area for the rest of the outlook period. && .AVIATION /02Z WEDNESDAY THROUGH SUNDAY/... VFR conditions for the valid TAF period and beyond. Winds west or southwest at 10 kt or less through Wednesday. There could be a few sprinkles or a light shower Wednesday afternoon, especially MRB. Do not believe that there will be an operational impact. Flow turns more southerly Thursday; again, no impacts. Remnants from Cindy look to be drawn to the Mid-Atlantic Friday into Saturday ahead of a cold front that crosses on Saturday. This may lead to enhanced rainfall and limited aviation conditions. && .MARINE...
-- Changed Discussion --
Winds have diminished over much of the waters but may linger tonight for the Drum Point to Smith Point/Tangier Sound area, where the pressure gradient would be greater. Winds will be southerly, or have a primary south component, through Thursday. From this vantage point, it appears as though gusts shouldn`t exceed 10-15 kt. Remnants from Cindy look to be drawn to the Mid-Atlantic Friday into Saturday ahead of a cold front that crosses on Saturday. This may lead to enhanced rainfall and SCA level winds over the Chesapeake Bay.
-- End Changed Discussion --
&& .LWX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
DC...None. MD...None. VA...None. WV...None. MARINE...Small Craft Advisory until 6 AM EDT Wednesday for ANZ534-537- 543.
-- End Changed Discussion --
&& $$ .UPDATE...WOODY! .PREVIOUS...HTS/BJL

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