Area Forecast Discussion
Issued by NWS Portland, ME

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000 FXUS61 KGYX 202038 AFDGYX Area Forecast Discussion National Weather Service Gray ME 338 PM EST Mon Feb 20 2017 .SYNOPSIS...
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High pressure will crest over the area tonight before gradually shifting on Tuesday. A warm front approaches from the west Tuesday night and early Wednesday bringing some light precipitation to the region. Temperatures will be on the increase for the remainder of the week with a few chances for showers mainly over the mountains. A more substantial system arrives for the weekend.
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&& .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
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Downsloping winds have cleared out cloud cover and allowed for another nice day despite being much cooler than we were yesterday. We are still above normal with a somewhat gusty NW flow in place. Tonight`s temperatures were a mix of short term meso guidance taking into account some weak cold air advection, clear skies, and winds going nearly calm overnight in many spots as high pressure crosses to the Atlantic. The valleys and other drainage areas will cool off quickly and we will see spots below 10 degrees in the mountains by morning. Elsewhere teens are expected.
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&& .SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
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High pressure will shift east on Tuesday as a warm front approaches from the west. In a very dry air mass we will have another quick warm up tomorrow with highs in the mid 30s to mid 40s...a pretty large diurnal jump with the sun angle increasing each day. After a mostly sunny start to the day high clouds will overspread the region during the afternoon. Warmer air arrives Tuesday night/Wednesday morning as temperatures drop below freezing at the surface. This weak overrunning pattern will create some areas of light wintry precipitation. The main concern will be a few hundredths of freezing rain which may fall towards morning mainly in the mountains and perhaps downstream over the coastal plain. Again this looks like a rather low impact event but may bring some impacts as far as slick driving surfaces.
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&& .LONG TERM /WEDNESDAY THROUGH MONDAY/...
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A warm zonal flow develops midweek. Models move a strong short wave through the midwest Thursday and into the Great Lakes by Saturday. In advance of this trof ridging and even warmer temps are expected for Thursday and Thursday night. By Friday a warm front will move north across the region as an increasing southerly flow develops to the east of the approaching trof. Some light precipitation is possible as this warm front moves north across the region. Friday night and Saturday will remain mild and went a little above guidance temps. The approaching upper trof will move east across southeast Canada late Saturday with a trailing cold front and associated showers that will continue into Saturday night. A return to a colder northwest flow will develop by Sunday.
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&& .AVIATION /20Z MONDAY THROUGH SATURDAY/...
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Short Term...VFR today through Tuesday with increasing cloud cover and possibly some MVFR decks very late Tuesday. Long Term...VFR conditions generally expected through the end of the week. A low pressure system cutting thru the Great Lakes will push a warm front thru the area Fri. This will likely bring an extended period of MVFR or lower. MVFR conditions in scattered showers will continue Saturday due to an approaching cold front.
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&& .MARINE...
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Short Term...Continuing Small Craft Advisories for low end conditions over the outer waters. Winds will decrease from west to east overnight as high pressure shifts towards the coast. Long Term...Winds and seas expected to remain below SCA thresholds thru the end of the week.
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&& .GYX WATCHES/WARNINGS/ADVISORIES...
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ME...None. NH...None. MARINE...Small Craft Advisory until 4 AM EST Tuesday for ANZ150-152-154.
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&& $$ NEAR TERM...Hanes SHORT TERM...Hanes LONG TERM...Marine

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