Area Forecast Discussion
Issued by NWS Portland, ME

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KGYX 231301 AFDGYX Area Forecast Discussion National Weather Service Gray ME 901 AM EDT Wed Aug 23 2017 .SYNOPSIS...
-- Changed Discussion --
A cold front will slide well offshore today. High pressure and drier air follows the front late today through the weekend. High pressure will then continue to dominate through the midweek period as low pressure develops over the mid Atlantic region.
-- End Changed Discussion --
-- Changed Discussion --
900 AM...At 12z the surface cold front extended from the rooftop of Maine southward into Penobscot Bay. Dewpoints remain in the 60s to near 70 immediately behind the front. The mountains and Connecticut valley have dewpoints in the 50s...and that drier and less humid air will advect eastward all the way to the coast by afternoon on a strengthening post frontal westerly flow. For this ESTF...near terms grids were adjusted to reflect current satellite trends as well as the latest mesonet. Prev Disc... 650 AM Update... Just a few lingering showers now racing ENE through the mountains this morning behind the main activity. Low stratus is moving offshore rapidly with a few pockets of low stratus and fog that have formed recently in the breaks in the cloud decks. This should mix out as warming ensues this morning and as westerly winds increase. Made a few changes to PoPs and weather grids for this update. Previous discussion... Large convective system which brought damaging winds to the region last night as well as widely varying amounts of precipitations (less than two tenths in Laconia to over an inch at Jaffrey) is still moving east and south this morning. Cold front has slowed along the coast and will bring additional QPF there and just inland for the next few hours before the next short wave kicker moves it offshore. Sprawling closed upper low will keep spinning over eastern Canada today pushing lobes of vorticity through the northeastern states. Drier air will filter in on gusty WNW winds today bringing sunny skies downwind of the mountains and foothills where clouds may hang on a little longer. A rogue sprinkle may occur over the highest peaks through this morning. Highs will be warmest along the coast and inland where we should see lower to mid 80s. Over the north 70s will be more common.
-- End Changed Discussion --
&& .SHORT TERM /8 PM THIS EVENING THROUGH 6 PM THURSDAY/... Drier and cooler air will filter in tonight as high pressure pushes in from the west. Westerly winds will lighten and dew points will tumble into the 40s and 50s. This will allow for temperatures to follow suit, with mid to upper 40s across the north to lower to mid 50s south. Patchy fog will develop in valleys and low lying spots. High pressure builds in farther on Thursday. Light northerly winds will continue to keep things dry and bring some cooler air down from Canada. Still, highs will be seasonable and in the upper 60s to upper 70s. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... Models in fairly good agreement in keeping upper trough meandering over the northeast for the end of the week and for much of the weekend as a surface high gradually builds in from the west. Cold pool aloft settling into the northeast will result in partly cloudy and cool nights with a mix of sun and clouds during the day Thursday night through Sunday. Nightly lows will range from the mid 40s north to the mid 50s south. Highs will top out from the mid 60s to the mid 70s south. Upper trough will gradually break down and fill Monday through Tuesday as high pressure remains in control over the northeast. Will see a slight warming trend with much of the forecast area reaching the lower to mid 70s by Tuesday. Shortwave approaching from the west will bring the next chance of precip into the northeast by midweek but models diverge quite a bit at this point so have generally followed SB solution bringing low chance pops into southern zones by Wednesday. && .AVIATION /13Z WEDNESDAY THROUGH SUNDAY/... Short term /through Wednesday Night/...Plenty of low level moisture still kicking around this morning with conditions ranging from IFR to VFR. As drier air works in from the NW today fog and stratus will push offshore or mix out. Gusty westerly winds of around 12G20KTS are expected along with VFR ceilings which will give way to SKC eventually. Valley fog along with marine fog will return tonight as dew point depressions drop. Long Term...VFR conditions are expected to prevail Thursday through the weekend other than some early morning valley fog. && .MARINE... Short Term /through Wednesday Night/...Seas remain in the 4-7 ft range and winds are just barely above small craft criteria this morning. Winds will decrease sooner than seas which may remain up through around noon. The outer waters of Penobscot Bay may need to be replaced by a Small Craft for Hazardous Seas for a few more hours at that time. Long Term...Small craft conditions are not expected Thursday through the weekend. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...Small Craft Advisory until noon EDT today for ANZ150>154. && $$ ES is the U.S. government's official web portal to all federal, state and local government web resources and services.