Area Forecast Discussion
Issued by NWS Portland, ME

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498 FXUS61 KGYX 251411 AFDGYX Area Forecast Discussion National Weather Service Gray ME 1011 AM EDT WED MAY 25 2016 .SYNOPSIS... Sunshine and warmer weather will return today ahead of a cold front. The front will bring clouds and a few showers and thunderstorms to the area this afternoon and early evening. A ridge of high pressure will build over the area tonight... then hold over the region on Thursday as a warm front approaches from the west. The warm front will stall over the region Thursday night and Friday and will finally push east of the region on Saturday. A cold front will cross the region Saturday night then stall just to our south on Sunday. The front will return north as a warm front on Memorial Day. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... UPDATE... Threat for some hail and gusty winds continues this afternoon and evening for Northern NH and adjacent western Maine. Coordination has occurred with Caribou for some enhanced wording for hail and gusty winds. Have updated the grids based on latest observations and mesoscale model data. Low level moisture continues to increase over the region while the atmosphere remains capped. Fog has mixed out in many inland areas and destabilization has begun. Northwest front aloft, favorable for strong thunderstorms will accompany a cold pool aloft and surface cold front as it passes through the region. Steep low level lapse rates will develop with the afternoon surface heating. CAPE values will continue increase while the cap is breaking. However, highest CAPE values, AOA 1000 J/KG may remain north of the border. Will continue to highlight the threat for storms over the afforementioned area in our products and social media. May have to nudge temperatures upward along the coast, depending on whether there will be a significant onshore flow or not. In the meantime, portions of southernmost NH may nudge 90 degrees this afternoon. PREV DISC... At o6z...weakening low pressure surface and aloft was over the gulf of Maine. While showers had ended...clouds and areas of drizzle and fog were lingering across the forecast area. Conditions will improve later this morning as the system slides well east of the area. The clouds and fog will break by shortly after sunrise with southerly flow and 850 millibar temperatures near plus 14C boosting temperatures into the 80s away from the coast where onshore trajectory will temper the heat today. shortwave impulse on GOES Water Vapor imagery north of the Great Lakes will race eastward with associated cold front over Quebec approaching international border region late today. While moisture and wind fields aren`t overly impressive...the modified BUFKIT forecast soundings for late today suggest gusty winds and small hail are a possibility with the stronger cells. I`ve included enhanced wording in the grids for that area. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... convection will quickly end this evening with loss of heating and as upper support exits the coast. Clearing and cool tonight behind the front with some late night valley stratus and fog as a ridge of high pressure noses in from the north. Lows tonight will range from upper 40s near the international border to around 60 at the New Hampshire seacoast. The ridge will crest across the area on Thursday with sunshine and warm temperatures. Highs will range from the mid 70s to lower 80s...before turning cooler by afternoon along the coast in a developing seabreeze. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... Model guidance is in good agreement on overall extended pattern into next week. Ridging will build into the region from the Wrn Atlantic...with the axis running thru New England. It will be a good potential pattern. Potential for some above normal temps...perhaps even work into parts of Nrn New England. But also the potential for a passing s/wv trof to knock the ridge down and backdoor some of the area. As things stand this morning...there is some consistency and consensus that a hotter day is possible Sat...while a backdoor cold front is possible Sun especially for Ern zones. With that boundary separating hot and cold air lingering nearby...a focus for showers or tstms will also be present into early next week. Cannot completely rule out rnfl in the extended...but there is not enough confidence for likely PoP either. && .AVIATION /14Z WEDNESDAY THROUGH SUNDAY/... Short Term /through Thursday/...Sct MVFR across the mtns this PM and evening with brief lcl ifr psb in -shra/tsra. Areas of mvfr and lcl ifr dvlpg btw 08-12z Thu in valley stratus and fog...bcmg vfr throughout aft 13z Thu. Long Term...In general high pressure looks to be in control of the forecast area thru early next week. VFR conditions should prevail as a result. However...there will be a risk for scattered shra or maybe even tstms and MVFR or local IFR that go with them. && .MARINE... Short Term /through Thursday/...No flags expected. Long Term...With ridging generally in place over the waters thru the extended...SCA conditions are not expected. && .FIRE WEATHER... Warm temperatures today but with scattered showers and thunderstorms later today. Good relative humidity recovery follows for tonight. Thursday will be one of the only dry days of the week. Afternoon relative humidity values on Thursday may hover near 30%...but winds will be light. We are forecasting all areas to receive rainfall this week albeit light. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...None. && $$ is the U.S. government's official web portal to all federal, state and local government web resources and services.