Area Forecast Discussion
Issued by NWS Sterling, VA
Issued by NWS Sterling, VA
750 FXUS61 KLWX 250135 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 935 PM EDT Sun Aug 24 2025 .SYNOPSIS... Shower and thunderstorm chances continue as the cold front crosses the area tonight. A strong dome of Canadian high pressure builds thereafter with near to below normal temperatures for much of next week. && .NEAR TERM /THROUGH MONDAY/... Earlier convection has been rapidly weakening with loss of daytime heating and as it outruns higher instability. However, a new shower has formed in its wake near Charlottesville, so at least some isolated activity remains possible until the synoptic cold front arrives. Additional convection exists along the front from central Pennsylvania to central West Virginia. While some of this could spill across the mountains in the next few hours, most guidance indicates it should dissipate by the time it reaches the I-81 corridor. As the front passes, a light wind will shift from south to northwest by morning with low temperatures dropping into the 50s west of I-81 to the 60s elsewhere. Before that happens, some patchy fog may develop (and is already showing signs of doing so), especially in southwestern portions of the CWA where it rained earlier. && .SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/... The cold front will exit the area early Monday after 06Z with showers ending shortly thereafter. Expect a slight bump in winds Monday as the front exits east and high pressure builds from the Ohio River Valley. Gusts of 15 to 20 mph are possible out of the north and northwest. Temps Monday will be below average with 70s to near 80 for most. Areas AOA 3.5kft in the Alleghenies likely don`t make it out of the 50s Monday - a sign of what is to come later this week with a true Autumnal airmass setting in. Lows Monday night will be in the 50s for most (60s along the water and in the city centers). High elevation valleys and bogs likely see the first frost of the season. Broad H5 troughing will remain Tuesday across the eastern CONUS with an area of Canadian sfc high pressure centered west of the area. This will result in highs only making it into the 70s to low 80s for most (upper 50s to 60s in mtns). Lows Tuesday night will be the coldest since spring for most locales with temps dropping into the 50s areawide (near 60 along waters and inner cities). Another night of patchy frost is possible in the favored locales. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... A broad upper-level trough pattern will remain in place across the East supporting cooler than normal temperatures. At the surface, Canadian high pressure will build into the area Wed into Thu keeping a dry air mass. The high pressure center settles overhead by Thu morning with cool morning lows in the 50s and widespread 40s west of the Blue Ridge Mountains. A cold front associated with a reinforcing shortwave-trough will drop down from the Great Lks Fri and may support a few showers. High pressure builds again for next weekend. The main story will be the cooler than normal temperatures, especially at night. && .AVIATION /02Z MONDAY THROUGH FRIDAY/... Convective chances have largely dwindled, although an isolated shower recently popped up near CHO, and some weakening convection may cross the mountains over the next few hours but likely dissipates before it reaches any of the terminals. Before the cold front arrives, some patchy fog may develop, especially at CHO where it rained earlier. Winds will be out of the south this evening, becoming northwest by around daybreak (a little earlier for CHO/MRB); a few gusts of 15-20 kts are possible through the morning hours. Winds will be northwest through Wednesday in the wake of the cold front while conditions remain VFR. No sig weather expected Wednesday through Thursday. && .MARINE... Southerly winds remain elevated this evening, but are generally in the 10 to 15 kt range. Otherwise, any shower and thunderstorm activity approaching from the west looks to weaken, with a couple relatively benign showers possible overnight ahead of an approaching cold front. The front itself looks to cross Monday morning, immediately behind which may be another brief period of gusts 15-20 kts (this time out of the NW). A secondary surge pushes across Monday night, with yet another potential push of potential SCA conditions Tuesday night into Wednesday. SCA conditions are possible again Thu into Thu night. && .TIDES/COASTAL FLOODING... Water levels will be slow to recede until a cold front clears the area Monday and winds shift to the NW. Additional minor coastal flooding will mainly be threshold in nature at a few locations. Highest confidence is at Annapolis (where an advisory continues through the AM high tide), but Solomons, Havre de Grace, Dahlgren, and Alexandria will also be close. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...Coastal Flood Advisory until 11 AM EDT Monday for MDZ014. VA...Coastal Flood Advisory until midnight EDT tonight for VAZ054. WV...None. MARINE...None. && $$ SYNOPSIS...DHOF/CPB NEAR TERM...ADS/DHOF SHORT TERM...DHOF/CPB LONG TERM...LFR AVIATION...ADS/LFR/DHOF/CPB MARINE...LFR/DHOF/CPB TIDES/COASTAL FLOODING...LWX