Area Forecast Discussion
Issued by NWS Portland, ME

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117 FXUS61 KGYX 021630 AFDGYX Area Forecast Discussion National Weather Service Gray ME 1130 AM EST Fri Dec 2 2016 .SYNOPSIS... Low pressure will gradually exit into the maritimes by tonight. In the wake of this disturbance, northwesterly flow will continue through the start of the weekend with snow showers in the northern mountains. A weak weather disturbance may bring a few snow showers to the region Monday. Otherwise, cold high pressure will settle in for the start of the new work week. A snow and rain mixture may enter the region late in the week. && .NEAR TERM /UNTIL 5 PM THIS AFTERNOON/... 1130 AM...For this ESTF update I adjusted near term grids to reflect current GOES visible imagery trends as well as to raise temperatures several degrees to mirror 16z mesonet. Added slight chance for --shra over lower Connecticut valley as well. Nil other changes. Prev Disc... 930 AM...For this ESTF made minor adjustments to near term grids to reflect current satellite trends and the 14z mesonet. Prev disc... 6am update... just minor adjustment to current temperatures. A steady pressure gradient has set up from southwest to northeast across the area in the wake of yesterdays low departing to the maritimes. This will keep west to northwesterly flow and through the day. Skies will be mostly clear in the coastal plain with clouds in the northern mountains. Upslope snow showers will continue through the day along the Canadian border. && .SHORT TERM /5 PM THIS AFTERNOON THROUGH 6 PM SATURDAY/... Overnight the flow will turn more northwesterly as the short wave moves through the region. This will increase the cross barrier flow with more upslope snow showers. The most favored locations will see another 2-3 inches overnight. The same shortwave will bring just enough moisture to spread clouds back across the entire region overnight keeping temperatures from dropping too far. Lows will remain in the low 30`s near the coast and low 20`s in the north. Saturday the short wave departs and cold air advection sets in under continued northwesterly flow. Temperatures will peak early in the morning and then drop through nightfall as the colder air moves in. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... A persistent northwesterly gradient continues Saturday night into Sunday morning as low pressure is slow to exit east of the Canadian Maritimes. This may trigger a few upslope flurries in the north and mountains as the last of the upsloping conditions end. A weak upper level disturbance will pass through the region on Monday, mostly bringing a few scattered snow showers to the region. Precipitation will be limited as the lower portion of atmosphere will remain relatively dry. Cold, high pressure becomes situated over New England for Tuesday. This will be accompanied by light winds. Models then diverge by Wednesday, with confidence levels not overly high at this point. The 00Z GFS splits two systems, one to our north and one to our south through Wednesday night before rapid cyclogenesis occurs over upstate New York on Thursday. In contrast, the Euro keeps most of the energy associated with a coastal system well to our south on Wednesday before low pressure tracks over Ohio Thursday. In this scenario, strong southernly winds would allow for moisture to rapidly move north from the Mid Atlantic region as the deep surface and upper level trough remains well to our west, over the Great Lakes region. In either event, there may be a mixture of rain and snow over the region. By the weekend, a large area of very cold air may sweep across the region as low pressure continues to rapidly develop over Canada. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... Short Term...MVFR conditions for HIE through Saturday as upslope flow continues. LEB will also see MVFR through this morning but scatter out as the winds shift to more northerly. Long Term...MVFR conditions are expected in the mountains into Sunday morning with VFR conditions expected downwind from the higher terrain. A period of MVFR conditions is possible Monday in a little light snow - but probability is pretty low. VFR returns Tuesday. && .MARINE... Short Term...Have extended the SCA through tonight. Wave height around 5-6 feet for the outer waters will continue through today before decreasing tonight as the northwesterly wind wave dominates over the swell from the departing system. Winds will continue to gust 25-30kts with an increase expected Saturday as cold air advection develops. SCA will likely need to be extended through the weekend. Due to the offshore flow... have not included the bays for this SCA. Long Term...A period of SCA conditions are possible on the ocean waters Saturday night - possibly into early Sunday. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...Small Craft Advisory until 7 PM EST this evening for ANZ150- 152-154. && $$ ES is the U.S. government's official web portal to all federal, state and local government web resources and services.