Area Forecast Discussion
Issued by NWS Sterling, VA

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000 FXUS61 KLWX 020234 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 934 PM EST Mon Mar 1 2021 .SYNOPSIS... One cold front has just cleared the region while a second cold front will cross the region later this evening. High pressure will then build in for Tuesday. Low pressure will pass to the south Wednesday. Another cold front will pass through Wednesday night and Canadian high pressure will build toward the area for late this week into the weekend. && .NEAR TERM /THROUGH TUESDAY/... The main pressure surge has passed, and with nightfall, winds are generally subsiding. Secondary surges seem unlikely to reach advisory criteria on a widescale basis, so the advisory has been cancelled for most areas. One exception is the Blue Ridge and peaks of the Alleghenies, where high elevation obs show strong winds continuing. There could still be some sporadic 30-45 mph gusts elsewhere, however. Flurries have been observed at times near the Pennsylvania border, but these should subside around/after midnight as a vort max moves to the east. Scattered stratocumulus should do likewise. Cold/dry advection continues through the night, so lows will be dropping below freezing across the entire area. High pressure builds slowly into the area Tuesday, but it will be considerably colder. Winds should slowly but surely relax, however, and there should also be more sunshine. Highs mostly in the 40s. && .SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/... Dry period continues through mid-week with high pressure. Lighter winds and not quite as cold Tuesday night as clouds increase a bit while low pressure passes to our south. Milder temperatures Wednesday will prevail thanks to warm advection aloft. Highs should rebound into the 50s. Dry cold front then pushes south across the region Wednesday night, but best cold advection will wait til Thursday, so lows Wednesday night won`t be any colder... in fact. likely slightly milder than tonight and Tuesday night, with many areas staying above freezing. && .LONG TERM /THURSDAY THROUGH MONDAY/... A breezy northwest flow will prevail Thursday into Friday and keep temperatures below average as the region sits between an upper-level low over eastern Canada and high pressure over the Great Lakes region. Dry and seasonably cool conditions continue Saturday into Sunday as Canadian high pressure moves overhead. This likely keeps an area of coastal low pressure to the south before heading out to sea. As the broad trough moves east early next week, temperatures will moderate towards seasonal levels. && .AVIATION /02Z TUESDAY THROUGH SATURDAY/... VFR conditions expected for the next several days. Main concern is northwest winds through Tuesday morning. Likely to see quite a bit of variability, especially this evening, as winds may subside for a bit, but then increase with sporadic gusts. Peak gust potential is probably in the 30-35 kt range. Overall the trend will be down, with winds becoming less than 10 kt by Tuesday evening. VFR conditions under northwest winds Thursday into Friday afternoon. Winds could gust to 30 knots behind the cold front Thursday into Friday. && .MARINE... Wind gusts have been quite variable, as the various boundaries/pressure rises have been non-uniform...not to mention slight nocturnal stability and warm air over cold waters. However, winds likely increase once again later this evening as secondary front moves through and air temperatures fall, especially over the wider waters of the Bay. After that, winds should gradually start to relax later tonight and Tuesday as gradient relaxes and high pressure builds in. The Gale Warning may be cancelled early. Another front approaching Wednesday with a low passing by to the south could also cause SCA conditions. A SCA is likely Thursday into Friday as a pressure gradient builds over the region and strong northwest flow prevails. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...None. VA...Wind Advisory until 4 AM EST Tuesday for VAZ507-508. WV...Wind Advisory until 4 AM EST Tuesday for WVZ501-505. MARINE...Small Craft Advisory from 11 AM to 6 PM EST Tuesday for ANZ530>543. Gale Warning until 11 AM EST Tuesday for ANZ530>543. && $$ SYNOPSIS...RCM NEAR TERM...ADS/RCM SHORT TERM...RCM LONG TERM...CPB AVIATION...ADS/RCM/CPB MARINE...ADS/RCM/CPB

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