Area Forecast Discussion
Issued by NWS Portland, ME

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000 FXUS61 KGYX 011409 AFDGYX Area Forecast Discussion National Weather Service Gray ME 909 AM EST Thu Dec 1 2016 .SYNOPSIS... Low pressure will move out of the region this morning with rain and snow coming to an end. Northwesterly flow will continue through the start of the weekend with snow showers in the northern mountains. Cold high pressure will settle in for the start of next week before another storm moves in mid week. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 905 AM...For this ESTF I adjusted near term grids to reflect satellite and radar trends as well as the current mesonet. Winter weather headlines have been dropped as well as the steadier precipitation exits the area. Prev Disc... 545 am...have dropped the southern part of the advisory, as reports from this area say mainly heavy rain at this point, with very little snow accumulations. Elevations above 2K ft may still be snowing and could see addl accums, but these areas are limited. Otherwise previous forecast unchanged other than T/Td/pops based on current obs. WArning snow may be hard to reach in central Somerset except over the higher terrain, but will hold for now, as there`s still half an inch or so of QPF, even at lower ratios will bring things close to warning, and snow will be wet and heavy. Previously...Rain will end from SW-NE this morning across all but the NE zones, where snow will mix with or change to rain during the morning hours, at all but the higher elevations. Should see enough for warning criteria in central Somerset, particular from Jackman N. Still uncertain about surrounding zones particular S FRanklin/Somerset, where some reports came in last night of mainly rain. Temps from mesonet sites still hovering just above freezing and radar Correlation coefficient shows melting band lifting NE over the last couple of hours. Have trimmed back to advisory until 9 AM, and could even end it sooner once some reports come in. Otherwise, look for some clearing this afternoon in southern NH and SW ME with mild highs of 50-55 in these areas, otherwise mostly in the 40s except far NE will be limited to mid-upper 30s. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/... W-NW flow will diminish somewhat overnight, but should stay dry and mainly clear outstay of the mountains. In the mountains will see upslope SHSN, and maybe even SHRA at lower elevations in the evening. Overall air mass is not that cold, but cyclonic flow aloft will help keep the upslope going, although for the most part it will stay light. On Friday, some weak ridging aloft will keep the morning mainly sunny on the coastal plain, and provide a bit of break of showers in the mtns, but next approaching low will begin to head SE out of the ST lawrence valley toward the crown of ME and clouds will be on the increase across the CWA, with SHRASN increasing again in the mountains and foothills. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... A long wave trough moves into the eastern portion of North American for the start of the weekend. This will keep temperatures cold with persistent northwesterly flow through the weekend. Upslope snow showers will continue through the weekend... with minor accumulation expected through Saturday in northern Coos and northern Oxford counties. Surface high pressure builds into the region on Monday as the trough moves overhead dropping 850mb temperatures to -10C. Expect mostly clear skies to allow for good radiational cooling and have dropped temperatures slightly below most guidance to account for this. Isolated mountain valleys may see temperatures near zero on Sunday night. The trough aloft begins to progress eastward at the start of next week. As it does the spread in timing of its departure results in increasing uncertainty in the forecast. By midweek /anywhere from Tuesday to Thursday/ the warmer air ties to push northward with an accompanying surface low and precipitation. After a cold weekend the tendency is for cold air to linger with the departing high pressure creating cold air damming in through coastal Maine which is being hinted at even in the global models at this far time frame. Cold air at the surface and warmer air coming in aloft sets us up for potentially messy mixed precipitation... however the uncertain timing of the arrival and northward extend of the warm air leaves ptype very much up for grabs. Due to the uncertainty have kept rain or snow only for ptype at this point. && .AVIATION /14Z THURSDAY THROUGH MONDAY/... Short Term...MAinly IFR or lower through sunrise, with improvement toVFR this afternoon. VFR will persist tonight and Friday, with the exception KHIE which will be subject to upslope showers and tempo flight restrictions tonight. Long Term... VFR conditions will prevail at all but HIE where upslope snow showers will yield periods of MVFR through Saturday. Then VFR returns through the start of next week. && .MARINE... Short Term...Gales and SCA will hold as they are, as strongest E winds are beginning to take shape and will continue through 12-14Z or so before diminishing. Will see a brief break today as low moves through and winds shift to W, but SCA will likely be needed for at least the open waters tonight. Long Term... Northwesterly flow and cold advection will keep SCA for the outer waters from Friday into Saturday. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...Small Craft Advisory until 11 AM EST this morning for ANZ153- 154. Gale Warning until 11 AM EST this morning for ANZ150>152. && $$ ES is the U.S. government's official web portal to all federal, state and local government web resources and services.