Area Forecast Discussion
Issued by NWS Portland, ME

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000 FXUS61 KGYX 272243 AAA AFDGYX Area Forecast Discussion...UPDATED National Weather Service Gray ME 643 PM EDT Tue Sep 27 2016 .SYNOPSIS... A cold front will move well offshore this evening. A strengthening northeast flow behind this frontal system will produce more clouds and patchy drizzle and fog overnight into the day on Wednesday. High pressure will gradually build into the region from the north late Wednesday and Wednesday night. The high will remain parked to our north while low pressure over the midwest drifts slowly north and east. Moisture from this system will gradually spread into the region Thursday and Friday. The best chance of rain will be this weekend when a large upper level low pressure system over the Great Lakes lifts to the north, spreading rain into New England. && .NEAR TERM /THROUGH WEDNESDAY/... Update...No major changes to the forecast for tonight. Will mostly be watching the low cloud deck forecast to return over much of the forecast area tonight. Background NE flow is already in place over parts of Wrn ME...and with time this should creep into NH as well. Low clouds should develop and push SW with time overnight. With WAA flow on top of this marine layer...I would not be surprised if areas of drizzle developed at some point tonight. For now will continue the mention of showers. Previous discussion...At 18z...a cold front was situated just offshore with a 1011 millibar low situated along it. Another weak boundary extended from the rooftop of Maine through the Saint Lawrence valley. Skies have broken out between these two features with partly sunny skies across the forecast area. NWS doppler radar mosaic showed scattered convection with this boundary over southeast Quebec. For tonight...the weak boundary over Quebec will settle south across the area with clouds and widely scattered showers. As the flow becomes more onshore overnight...we`ll see lower clouds and patchy drizzle and fog develop. Lows will range from the upper 40s to lower 50s. && .SHORT TERM /WEDNESDAY NIGHT/... On Wednesday...we`ll see slow improvement from Northeast to Southwest as High pressure centered near the Gaspe Peninsula gradually spreads drier air into the area. It should remain mostly cloudy over much of southern and western New Hampshire and extreme southwest Maine while the rest of the area sees partial clearing. It`ll be cooler then today in a strengthening Northeast breeze with highs only in the mid 50s to lower 60s. Clouds begin to spread back north on Wednesday night as the system over the midwest attempts to move into northern New England. && .LONG TERM /THURSDAY THROUGH TUESDAY/... Thursday morning begins with a large scale closed upper level low firmly entrenched over the nations mid-section. Southerly flow aloft over New England will keep temperatures at least near normal despite variable cloudiness and intermittent precipitation. The closed low looks like it will remain over the Ohio river valley through Friday and at least into Saturday before starting to migrate to the north and east. The low will begin to weaken a bit on Sunday and Sunday night before becoming an open wave late Monday night. The entire extended period will be dominated by this upper level low. While it may not produce a tremendous amount of rain... it will create mostly cloudy skies and rain showers throughout the period. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... Short Term/through Wednesday night/...VFR will lower to MVFR tonight with lcl IFR psb in drizzle and fog. Conditions improve to MVFR throughout aft 13z Wed, bcmg VFR by 17z over northern NH eastward into much of ME. Long Term...A slow moving closed upper level low will generate some flight restrictions at times over the weekend. Expect cloudy skies in the long term with scattered rain showers. Will likely see some MVFR/IFR cigs and vsbys associated with the showers. && .MARINE... Short Term /through Wednesday night/...Strengthening Northeast flow will bring SCA conditions outside the bays tonight and continuing through Wednesday. It`s likely the SCA will need to be extended. Long Term...Will likely need a small craft advisory for most of the weekend as a slow moving system will generate onshore flow. Seas are expected to remain above advisory criteria into at least Sunday. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...Small Craft Advisory from 2 AM to 8 PM EDT Wednesday for ANZ150-152-154. && $$ NEAR TERM...Legro

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