Area Forecast Discussion
Issued by NWS Portland, ME

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254 FXUS61 KGYX 261114 AFDGYX Area Forecast Discussion National Weather Service Gray ME 714 AM EDT Wed Oct 26 2016 .SYNOPSIS... A trough of low pressure will linger over the area today. A narrow ridge of high pressure will build in from the west overnight and will slide off to the east on Thursday. Low pressure will approach from the west Thursday afternoon and will slowly move east through the region Thursday night and Friday. A ridge of high pressure will build in from the west Friday night and will be quickly followed by a cold front on Saturday. High pressure will build in from the west saturday night through Monday. && 11z update... Quick update to adjust temp/td/sky grids. Skies are fairly clear downwind of the mountains early this morning but expect clouds to fill in as heating gets going later this morning. Aside from a few stray sprinkles or flurries in the mountains...should see a dry day. No other changes planned attm. Previous discussion... .NEAR TERM /UNTIL 6 PM THIS EVENING/... One more day of cyclonic flow over the region as upper low gradually releases its grip on the area. Should see a day much like Tuesday with cloudy skies in the mountains with scattered rain and snow showers. Remainder of the forecast area will see a mix of sun and clouds along with much less wind. Highs will range from the mid to upper 30s north and will range through the 40s south. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... Narrow surface ridge will build in from the west overnight. Should see diminishing clouds during the evening downwind of the mountains and skies clearing in the north after midnight. Expect radiational cooling with lows ranging through the 20s in most locations. High pressure will quickly slide off to the east on Thursday as low pressure approaches from the west. High clouds will be edging into southwest zones by around daybreak and will quickly overspread the forecast area in the afternoon. Expect rain to push into southwest New Hampshire by mid afternoon and may see a brief period of sleet and and wet snow at the onset...especially over the higher terrain. Highs will top out in the lower to mid 40s. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... Upcoming hazard potential: Accumulating snows north Thursday night into Friday, in particular the higher terrain. Upper level low quickly deepens and becomes negatively tilted as it progresses eastward Thursday night. Main surface low will be situated over northern New York State Thursday night as cyclongenesis takes place in area of strong diffluence aloft and strong low level warm air advection along the Southern New England coastline. This favorable track for enhanced precipitation will move the surface low from the Mass-New Hampshire border and into the Gulf of Maine by Friday. Boundary layer temperatures will be warm, however thermal profiles suggest temperatures may be cold enough for accumulating snow over northern areas. Far northern areas may reach the snow advisory range and we are well coordinated with WPC and CAR at this time. There may be some enhanced snowfall across the highest peaks. In particular, the Mount Washington area and the Presidentials will need to be monitored for potential enhanced accumulating snows above 5000 feet. System slowly departs Friday night with another trough approaching from the west Saturday. This will mainly be an all rain event. High pressure will then build over the region from Canada late this weekend and early next week, however this surface ridge will not tap overly cold air. && .AVIATION /11Z WEDNESDAY THROUGH SUNDAY/... Short Term...areas of MVFR ceilings in the mountains this morning...otherwise VFR. VFR tonight through Thursday morning. MVFR/IFR ceilings developing Thursday afternoon. Long Term...Mainly IFR conditions Thursday night into Friday with locally LIFR conditions. There could be a period of LLWS. Conditions improving thereafter. && .MARINE... Short Term...Dropping SCA`s with the morning package. Long Term...Will be issuing a Gale Watch for the outer waters this forecast package for late Thursday night into Friday morning. Sufficient southeasterly gradient ahead of approaching low to briefly put the outer waters into a Gale, followed by backing winds Friday morning. && .GYX WATCHES/WARNINGS/ADVISORIES...
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ME...None. NH...None. MARINE...Gale Watch from late Thursday night through Friday morning for ANZ150>152-154.
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