Area Forecast Discussion
Issued by NWS Sterling, VA
Issued by NWS Sterling, VA
185 FXUS61 KLWX 030751 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 351 AM EDT Sun Aug 3 2025 .SYNOPSIS... Dry conditions, low humidity, and seasonably cool temperatures are expected through Monday as broad high pressure drifts across the Northeast. The high will begin to weaken as it moves offshore Tuesday into Wednesday allowing humidity and storm chances to return by mid week. An area of low pressure may develop and track up the East Coast as a frontal boundary approaches from the west during the second half of the week. && .NEAR TERM /TODAY THROUGH TUESDAY MORNING/... High pressure center over Pennsylvania will remain wedged down into the area through Tuesday morning keeping tranquil conditions with light winds and few-sct stratocumulus during the day. Temperatures today will be a little warmer than Saturday due to less clouds and slightly modifying air mass. Temperatures continue to rise Monday into Tuesday as heights rise. Cool at night with 50s west of Route 15 and low to mid 60s east of there. && .SHORT TERM /TUESDAY AFTERNOON THROUGH TUESDAY NIGHT/... High level moisture will begin to increase across the area Monday night as a cutoff upper level trough approaches from the west. Uncertainty in the fcst begins to show up as early as Tuesday afternoon when some EPS members show light rain arriving across southwest areas. Given the slow nature of the cutoff upper level trough and the strong high pressure center settling over Quebec, the slower solutions are more likely to verify. This means rain is not likely to arrive across our area until the day Wednesday. Even if rain arrives later than fcst or fails to materialize at all as some guidance suggest, expect increasingly cloudy skies Wed into the second half of the week as onshore flow strengthens. Some light rain or drizzle is possible Tue night into Wed across southwest areas as a low overcast develops and easterly upslope flow develops. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... The forecast for the second half of the upcoming week is mired with uncertainty. A slow-moving, nearly cutoff upper-level trough will slowly approach from the west. Meanwhile, high pressure off the Northeast coast will result in a baroclinic zone which may spawn an area of low pressure off the Southeast by mid week. Subtleties in the evolution and interaction between the trough approaching from the west and the low offshore are the source of the uncertainty in the forecast. What is certain is onshore flow and increased cloud cover and humidity, but the specifics surrounding rain chances and amounts or the strength of the wind are highly uncertain. && .AVIATION /07Z SUNDAY THROUGH THURSDAY/... Tranquil conditions expected through Tue night. Light winds and P6SM SKC. Low clouds may develop Tue night into Wed morning with some CIG restrictions possible. Lower CIGs are possible Wed-Thu in onshore flow, but the degree of any restrictions is uncertain given large model spread. && .MARINE... Given lack of sfc gusts above 15 kt and neutral trend on winds, have canceled the SCA for the southern waters. Winds are expected to increase Wed afternoon into the second half of the week. Onshore flow may increase during the second half of the week as low pressure develops off the Southeast coast. && .TIDES/COASTAL FLOODING... Onshore flow will linger much of the week. The strength of the wind becomes increasingly uncertain the second half of the week, but multiple rounds of at least minor tidal flooding are possible along vulnerable shoreline over the next several days. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...Coastal Flood Advisory until 8 AM EDT this morning for MDZ014. VA...None. WV...None. MARINE...None. && $$ SYNOPSIS...DHOF NEAR TERM...LFR SHORT TERM...LFR/EST LONG TERM...DHOF AVIATION...LFR/DHOF MARINE...LFR/DHOF TIDES/COASTAL FLOODING...DHOF