Area Forecast Discussion
Issued by NWS Portland, ME

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000 FXUS61 KGYX 161337 AFDGYX Area Forecast Discussion...UPDATED National Weather Service Gray ME 937 AM EDT Thu Mar 16 2017 .SYNOPSIS... Low pressure will continue to pull away to the northeast today through tonight. High pressure will build in from the west on Friday and will crest over the region Friday night. Low pressure will pass out to sea south of New England Saturday. High pressure will gradually build in from the west Sunday through Monday. A cold front will cross the region Monday night followed by a secondary cold front Tuesday night. && .NEAR TERM /UNTIL 6 PM THIS EVENING/...
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1337Z Update... Minor changes to decrease PoPs slightly over the foothills and keep them mostly confined to the mountains based on latest near and short term guidance. QPF, temperatures, dew points, and wave heights were also adjusted based on current observations. 11z update... Quick update to adjust temps/td/sky grids based on current obs. Mostly clear skies downwind of the mountains will gradually give way to clouds by late morning/early afternoon. Aside from a few flurries in the north...remainder of the day should be dry. No other changes planned attm. Previous discussion... Cyclonic flow will persist over the region today through tonight as low pressure over the maritimes continues to slowly drift of to the northeast. Will see a day much like Wednesday downwind of the mountains with mostly clear skies this morning giving way to clouds in the afternoon. In the north skies will remain cloudy with occasional snow showers. Temperatures across the region will range through the 20s to near 30 degrees.
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&& .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/... Clouds will persist in the mountains overnight along with a few stray flurries. Skies will gradually clear downwind of the mountains this evening. Low temps overnight will range from 5 to 10 north and will range through the teens south. A narrow ridge of high pressure will build in from the west on Friday. Lingering moisture from departing low pressure will produce a mix of sun and clouds during the morning before gradually clearing sets in during the afternoon. Highs on Friday will range from the mid 20s north to the mid 30s south. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... The extended begins with high pressure nosing into the region from Ontario Fri night. That should help see temps below guidance...especially over the fresh snow pack. I dropped the usual suspects 3 to 4 degrees below guidance. Then for the second half of Sat we will watch a s/wv trof dig thru the Great Lakes. Clouds should increase from the W in the evening as the upper trof approaches. That H5 low has continued to slip Swd with each successive model run...and 16.00z GFS is trending in the direction of the Srn ECMWF. Both models are a near miss for parts of the forecast area...as frontogenesis aloft clips parts of Srn NH and coastal Wrn ME. 15.12z ECMWF EPS continues to show a cluster of individual members NW and closer to Cape Cod...and as such I am not willing to totally write this system off yet. There is definitely some feature in the flow that is causing about 1 in 4 or 5 members to amplify closer to the coast of New England. I suspect that the s/wv trof moving into the Pacific Northwest is playing a role...and that should be fully sampled by regional raobs with the 12z soundings. If any appreciable N trend fails to materialize with the 12z runs...it will probably be time to trim the likely PoP out of the forecast. As that system pulls away early next week...brief surface ridging crosses the area ahead of the next trof. This one looks to usher in yet another blast of Arctic air midweek. While not as cold as previous cold snaps...H8 temps around -20C...or about 10 to 15 degrees below normal...are forecast. That should add to an already well below normal monthly average temp. && .AVIATION /14Z THURSDAY THROUGH MONDAY/... Short Term...VFR today through tonight with areas of MVFR ceilings in the mountains. VFR Friday. Long Term...VFR conditions prevail Sat under the influence of high pressure. Upper trof swings thru Sat evening...with SHSN in the mtns. Farther S...some -SN may make it as far N at CON during the overnight. A period of IFR conditions is possible across Srn NH terminals...but confidence is low. Any lingering -SN moves out Sun. && .MARINE...
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Short Term...Dropping gales for SCAs valid through this afternoon. Long Term...High pressure will nose over the waters to begin Sat. As an upper trof swings across the Northeast...low pressure will develop S of New England. It is forecast to deepen quickly...but just a hair too far E to bring widespread significant impacts to the waters. A period of near gale force gusts is possible on the outer waters however. Winds and seas diminish early next week...before a cold front crosses the waters midweek.
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&& .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...Small Craft Advisory until 6 PM EDT this evening for ANZ150>154. && $$ NEAR TERM...Hanes SHORT TERM...Sinsabaugh LONG TERM...Legro

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