Area Forecast Discussion
Issued by NWS Portland, ME

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000 FXUS61 KGYX 310404 AFDGYX Area Forecast Discussion National Weather Service Gray ME 1204 AM EDT TUE MAY 31 2016 .SYNOPSIS... A weak cold front will move into the region tonight then dissipate. Another cold front will move through the region on Tuesday but not before temperatures warm into the 80s again. High pressure will build in from the northeast Tuesday night through at least Thursday night with cooler temperatures but fair weather. A front moves through the area on Friday with a chance of showers. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
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midnight update... shower activity has come to an end. stratus deck is moving through Massachusetts and will impact the coastal locations overnight. Inland expect fog to form in the river valleys early this morning. A weak cold front will approach from the northwest later this afternoon. This may be enough to trigger a few thunderstorms. With some CAPE in place along with modest deep layer shear, a few storms may produce gusty winds and small hail. At this time it appears as though the best chance of strong storms will be across the western ME mountains as well as near the MA/NH border. One or two severe storms are not out of the question. The activity should wane after sunset with loss of daytime heating. Thereafter, areas of fog are expected to develop overnight but it should remain dry.
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&& .SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/... Another cold front will approach from the northwest on Tuesday. Ahead of this front temperatures should climb well into the 80s. Dewpoints should mix out some and therefore limit instability. The best forcing for ascent will be across northernmost zones and that is where we have chance pops for showers and thunderstorms. Cooler and drier air moves in Tuesday night as high pressure builds in. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... High pressure builds into eastern Maine and the Canadian Maritimes on Wednesday with a cool easterly flow setting up over much of New England. This pattern continues for Thursday with the flow becoming a little more southeasterly as the high shifts east. Temperatures will be warmest to the west of the mountains (mid to upper 70s) and coolest near the coast (upper 60s to near 70). With drier air in place than we have seen recently, nighttime temperatures will cool into the 40s to low 50s most nights. On Friday an upper level trough moving through Quebec send a cold front toward our area. Ahead of it, warm/moist air will be sent northward into our area. There will be a chance of showers as the trough moves through Friday with the front making its way to the coast by Saturday morning. Temperatures should be a few degrees warmer behind the front Saturday due to less cloud cover and better mixing behind the front... generally in the 70s. A ridge briefly builds over the area on Sunday but low level winds will still be off the water, so temperatures stay relatively cool particularly in Maine. The next upper level trough crossing through the Great Lakes will bring rain chances late Sunday into Monday. GFS and ECMWF differ a bit on how to handle this system, with the GFS developing a deeper and slower-moving upper level wave and a more complex low pressure system while the ECMWF taking a more progressive approach with a weaker low and shorter duration of rainfall. Think the ECMWF probably has a little better handle on this system at the moment as the initial wave in the GFS tracking through the Northern Plains seems to be deepened too strongly by convection in the model. The overall conclusion is that there is a pretty decent chance for a wetting rain over all of the area early next week sometime from late Sunday into Tuesday. && .AVIATION /04Z TUESDAY THROUGH SATURDAY/... Short Term...VFR conditions may temporarily give way to local MVFR/IFR conditions in showers and possibly a thunderstorm late this afternoon and early evening. Areas of fog may develop overnight due to a moist boundary layer...especially on the midcoast of Maine. Otherwise, VFR conditions are expected Tuesday and Tuesday night. Long Term...Expect VFR conditions Wednesday through Thursday with the possibility of fog developing in the valleys at night. There will be a chance of showers on Friday and the low level southeasterly flow could transport some low clouds off the Gulf of Maine and into eastern New Hampshire and western Maine at some point with IFR conditions possible. Conditions improve to VFR again behind a cold front on Saturday. && .MARINE... Short Term...Seas may reach 5 ft on the ocean waters overnight tonight and into early Tuesday morning. However will hold off on SCA as it is marginal and confidence is not high at this time. Long Term...High pressure tracking through the Canadian Maritimes will bring a light easterly to southeasterly wind flow to the Gulf of Maine through the end of the week. With light winds expected, seas will also likely remain below 5 feet. && .FIRE WEATHER... RH values are expected to drop to between 25 and 35 percent during the afternoon hours on Tuesday along with some gusts around 20 mph. This may increase fire danger a bit but with recent rain and greenup it won`t require any sort of headline. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...None. && $$ SYNOPSIS... NEAR TERM...Curtis SHORT TERM... LONG TERM... AVIATION... MARINE... FIRE WEATHER... is the U.S. government's official web portal to all federal, state and local government web resources and services.