Area Forecast Discussion
Issued by NWS Sterling, VA

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473 FXUS61 KLWX 142117 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 417 PM EST Sat Jan 14 2017 .SYNOPSIS... High pressure will build over the area again through Sunday night. A stationary front over the southern mid-Atlantic states will return north as a warm front Tuesday and Tuesday night. A weak cold front will push through the area Wednesday. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... Freezing rain advisory was canceled along portions of the Allegheny Front. Temperatures have warmed above freezing. Winter weather advisory has been extended through tonight. Temperatures across northern MD are at or below freezing. Another round of rain will cross the Mid- Atlantic this evening. Freezing rain is expected in these locations. Rain is expected elsewhere. Some mesonets are hovering freezing between DC and Baltimore this evening however pavement temperatures are in the mid 30s. Will monitor temperatures closely this evening. Prev discussion... Sfc temperatures along the Mason-Dixon line remain around freezing and will hold steady through the night or perhaps rise a bit, so -fzra/-fzdz will remain possible mainly over elevated surfaces and any untreated surfaces. Over the Appalachians, sfc temps are expected to drop below freezing again, so -fzdz and fzfg are possible. For those areas, the winter wx/fzra advzy may need to be extended for a few more hours, but will let next shift decide. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/... Clouds will scatter out quickly during the morning becoming clear by afternoon under strengthening NNW flow. Temperatures will rise into the mid 40s. There could be enough lift and saturation over the central Shenandoah valley for some light rain or drizzle Sunday afternoon. Deeper moisture will start spreading back again into the area Sun night and Mon as a storm system begins to organize over the mid section of the country. Any precip looks to be light and in the form of rain. && .LONG TERM /TUESDAY THROUGH SATURDAY/... High pressure offshore the eastern U.S. Coast will interact with a low pressure system over the Great Lakes region Tuesday and Tuesday night to produce a mild southerly flow. Along with milder temperatures will be the threat for rain, moderate at times, later on Tuesday into Tuesday night. An associated cold front will move across the region as the low pressure system pushes across northern New England Wednesday into Wednesday night. The chance for rain may linger Wednesday, but then should taper to partial clearing skies, cooler temperatures, and perhaps some upslope snow showers in the higher elevations of the Appalachians. High pressure should build across the region Thursday and Thursday night before moving offshore the eastern U.S. Coast by Friday. Drier conditions with seasonable to mild temperatures are anticipated each period. A warm front should work its way northward up the Appalachian Front later Friday into Friday night, bringing a chance for a few rain showers. During the day Saturday, a second, more stronger warm front could work its way northward across the central and eastern parts of our region. Even milder air and the chance for rain showers exist with this warm front as well. && .AVIATION /21Z SATURDAY THROUGH THURSDAY/... Ifr/lifr cigs and vsbys expected through this evening with occasional drizzle. Conditions improve rapidly after 12Z Sun if not sooner under strengthening NNW flow. Mvfr or ifr conditions Tuesday. Ifr to lifr conditions Tuesday night with rain showers increasing in coverage. Winds south around 5 knots Tuesday, becoming southwest 5 to 10 knots Tuesday night. && .MARINE... Light and variable winds tonight. Possible SCA conditions Sun afternoon middle and lower Chesapeake Bay. No marine hazards Tuesday and Tuesday night. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...Winter Weather Advisory until 11 PM EST this evening for MDZ003>006-501-502-507. VA...None. WV...Winter Weather Advisory until 11 PM EST this evening for WVZ051-503-504. MARINE...None. && $$ Update...HSK SYNOPSIS...LFR NEAR TERM...LFR SHORT TERM...LFR LONG TERM...KLW AVIATION...LFR/KLW MARINE...LFR/KLW is the U.S. government's official web portal to all federal, state and local government web resources and services.