Area Forecast Discussion
Issued by NWS Sterling, VA

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000 FXUS61 KLWX 270800 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 400 AM EDT FRI MAY 27 2016 .SYNOPSIS... High pressure will remain over the area through the end of the week. Low pressure may affect the region Memorial Day through Tuesday. Weak high pressure builds for the middle of next week. A cold front may push through the region at the end of next week. && .NEAR TERM /TODAY/... An upper level ridge is across the eastern conus with a warm core low just NE of the Bahamas. A light south wind will continue across the area into Sunday with the surface high out by Bermuda. Dewpoints are currently in the mid 60s and should increase to 70F today as moisture advection continues. Similar temperatures to yesterday expected...maxima upper 80s. The added moisture will result in higher peak heat indices...low 90s. Today should be the hottest day of the stretch with a slight dip in moisture expected Saturday. Diurnal convective thunderstorm pattern expected again today with highest pops (60) in the terrain west from the Blue Ridge and low chances east of the piedmont from bay breeze boundaries. Tried to avoid overpopping east of the Blue Ridge again with low chances 2pm to 8pm. Any activity should persist into the evening with isolated thunderstorms mainly west from the piedmont...minima upper 60s to 70F. && .SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/... Upper level ridge builds into the area from the east north of a developing low off the SC coast Saturday. Associated height rises create a subsidence inversion and greatly limit convective development. Exception is chance PoPs for thunderstorms that were maintained in the Allegheny Mountains where terrain and less influence from the high combine to allow scattered activity. Maxima mid 80s again with dewpoints down into the mid 60s with mid to upper 80s heat indices. The warm core low is expected to be near the SC coast Sunday. Associated inverted trough extends north into the area with likely showers and thunderstorms for north-central VA and southern MD. Maxima mid to upper 80s in northern and northwestern portions of the CWA where rain/clouds arrive last. Expect low to mid 80s south of there. && .LONG TERM /MONDAY THROUGH THURSDAY/...
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Low pressure slowly moving northward up the southeast coast Monday will provide extensive cloud cover and chances of rain for Memorial Day. Highs will be around 80. Euro is implying an upper level short wave will be tracking along the US-Canada border late Monday. Question is whether this will be able to lift the low pressure area across the Mid Atlantic away from the area - MEX/GFS is giving area clear skies Tuesday. I`m a bit skeptical of this happening and would prefer to keep a chance of showers/thunderstorms over the region. I`ve written for the past few nights that the Superblend are trending cold in the first part of next week. This still seems to be the case. GFS and Euro are forecasting mid 80s Tuesday-Wednesday while Sblend is going mid 70s. This may turn out to be cloud-dependent but believe the odds are higher towards at least reaching 80. The next thing to talk about is a possible cold frontal passage late next week. This would lead to a return to the western ridge/eastern trough that N America saw for a decent portion of the winter.
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&& .AVIATION /08Z FRIDAY THROUGH TUESDAY/...
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Light southerly flow and patchy valley fog through sunrise. Diurnal thunderstorms are expected to form again with first storms west of the DC metros in the terrain. IFR conditions expected in heaviest activity. Southerly flow continues through Saturday. However, upper level high pressure limits thunderstorms Saturday. Showers and thunderstorms spread north from a low along the South Carolina coast Sunday. Showers and thunderstorms spread north from a low along the South Carolina coast Sunday...continuing Monday.
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&& .MARINE... Light southerly flow persists through Saturday as high pressure lingers near Bermuda. SCA for southerly channeling late this afternoon through midnight for southern MD Bay waters. Isolated thunderstorms possible again across the waters. Southerly channeling possible again Saturday evening. Rain and thunderstorms spread north across the waters Sunday into Sunday night from low pressure along the South Carolina coast. && .LWX WATCHES/WARNINGS/ADVISORIES...
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DC...None. MD...None. VA...None. WV...None. MARINE...Small Craft Advisory from 5 PM this afternoon to 2 AM EDT Saturday for ANZ533-534-537-543.
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&& $$ PRODUCTS...BAJ/WOODY!

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