Key MESSAGE 1, A shortwave will swing through the Mid Atlantic tonight and push a weak backdoor cool front through ENC. This may trigger some overnight showers tonight, and rain chances remain in the 20-40% range, highest across northern zones where better forcing is located.
KEY MESSAGE 2, Temperatures gradually warm through the weekend. Upper level trough that is currently overhead will gradually push offshore with more zonal flow, albeit above normal heights, setting up across the Eastern Seaboard Sunday into Monday. Dry conditions expected this weekend. Sunday and Monday are likely the warmest days, reaching well into the 80s interior zones (70s coast), although uncertainty has increased some on Monday as 20/12z guidance is a bit faster with the frontal passage which may lead to cooler high temps. Fire weather concerns should remain rather low, despite the mainly dry conditions, due to light winds forecast through the weekend with high pressure dominating.
KEY MESSAGE 3, Stronger shortwave and deeper upper troughing track across the Northeast and Mid-Atlantic Mon bringing a backdoor cold front quickly through the area. Several 20/12Z models are signaling a faster fropa with the front across the southern portions of the FA by 18z Monday. Pops have decreased with this update, as the front is moisture starved and GOM cut off. Instability is negligible due to lack of moisture and faster timing of the front keeping thunder chances low. The main sensible weather with this front will be a rapid increase of northerly winds behind it with temps dropping through the afternoon and into evening.
18z Friday through Wednesday VFR conditions expected through the period with clear and light southerly winds expected. Winds become westerly Saturday 5-10 kt with gusts to around 15 kt ahead of a weak backdoor cold front moving into the area from the north late Saturday afternoon. Isolated showers possible Saturday morning ahead of the weak front and will see lowering ceiling but should remain VFR. The front will push through the area late Saturday.
Outlook, A chance of lowering visibilities Sunday morning with clear skies, light to calm winds, and dewpoints in the low 50s. A frontal system Monday brings gustier winds, currently forecast to be around 20 knots out of the east/northeast along with isolated to widely scattered showers and thunderstorms with sub-VFR ceilings possible.
High pressure over the waters with light and variable winds around 10 kt or less with seas around 3-5 ft, although Diamond Buoy has occasionally reported seas up to 6 ft. High pressure shifts further offshore tonight with swrly gradient tightening as a cold front approaches from the north with winds increasing to 15-25 kt and seas building up to 4-7 ft, highest over the warm Gulf waters and Pamlico Sound. Have issued a short duration SCA tonight through mid day Monday for the Pamlico Sound and waters south of Oregon Inlet where winds will be strongest.
Outlook: Winds then turn swrly on Sunday once again as high pressure weakens over the area. On Monday, SW wind increase with 10-20 kt winds expected, with some 25+ kt possible on the Gulf Stream waters, ahead of approaching cold front. Front passes through Mon afternoon with stout 20-30 kt northerly winds developing in its wake through Mon night into Tue, with seas rapidly building to 6+ ft behind the front later Monday. Some gale force gusts not out of the question, particularly on the Gulf waters.
Nc, none. Marine, small craft advisory from 2 am to 10 am EDT Saturday for amz135. Small craft advisory until 2 pm EDT Saturday for amz152-154. Small craft advisory from 5 am to 2 pm EDT Saturday for amz156- 158.
