


Area Forecast Discussion
Issued by NWS Portland, ME
Issued by NWS Portland, ME
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875 FXUS61 KGYX 032255 AFDGYX Area Forecast Discussion National Weather Service Gray ME 655 PM EDT Thu Apr 3 2025 .SYNOPSIS... Fair weather returns tomorrow as high pressure builds into the region. Yet another chance of a wintry mix arrives this weekend as a storm heads through the St. Lawrence River Valley. The pattern will remain unsettled into early next week with near to below average temperatures. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... 700 PM update... Minor changes to reflect latest observational trends. It will continue to be a damp evening with cool temperatures, except over extreme southern NH where some readings are near 60 degrees at this hour. Previously... With the front passed, most precipitation moves out of the region. Winds will gradually shift from southwesterlies to northwesterlies tonight. Residual moisture in the mountains will allow for a few more showers to develop there this evening. Fog is likely to develop over the Gulf of Maine, as warm air moves over cold open waters. Dense, overcast skies overnight will allow for warmer low temperatures tonight, with temperatures in the 40s. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/... Tomorrow morning, high pressure arrives and will allow for clearing skies through the day. Clearing skies will allow southern New Hampshire and coastal Maine to break into the 50s tomorrow, with some 60s possible in southern New Hampshire. Northwesterly flow should allow for cooler high temperatures in the mountains, with high temperatures in the lower 40s. A system will arrive from the west, bringing increasing cloudiness over the area tomorrow night. && .LONG TERM /SATURDAY THROUGH THURSDAY/... Overview: A wave of low pressure will follow exiting high pres into the Northeast this weekend, bringing another round of rain and wintry precipitation to the area. This lingers through Sunday night before high pressure quickly moves through northern New England into Monday. Another disturbance will move through the region through early to mid week. Details: Main focus is on this weekend`s event which appears likely to include another round of mixed precipitation. Low pressure will initially glide along a stationary front well to the south, with overunning precipitation spreading throughout the forecast area Saturday afternoon. Surface temps and profile temps will play a role in precip types for the area. CAD appears to be weak as onshore flow moves over the coast and interior for a couple hours ahead of precip onset. This will at least allow surface temps to rise above freezing for all but the mountains of northern NH and western ME. Warm layer above the surface will bring the chance for wintry mix across northern areas. NBM probs are high for both a period of sleet but also freezing rain where sfc temps stay cooler in the mountains. Confidence in values and area should improve here on out, but a lot of current uncertainty revolves around how far north warm front gets this weekend. With warm sfc temps leading into the event, would need greater CAA to make ice accretion greater. Will need to watch QPF Saturday evening and overnight as accretion rates may be greater then vs. Saturday evening. Should the warm front successfully push north Sunday, remaining precip falls as rain. This exiting system will flush the region as a cold front arrives. Guidance keeps its movement slow, and this could result in additional precip w/ another wave traveling northeast. EPS has been fairly locked on positioning for a number of runs, with GEFS wavering a bit more. The passage is close enough to include some inland mention of showers lingering into Monday, perhaps as light snow. The active pattern continues as a compact low exits the eastern Great Lakes into Tuesday. This has slowed somewhat, and phasing with the complex pushing off the East Coast isn`t as complete. Precip may be snow on the heels of the exiting cold front, and may need to watch for the chance of snow squalls Tues afternoon should lapse rates increase. && .AVIATION /00Z FRIDAY THROUGH TUESDAY/... Short Term...IFR is expected this afternoon as low stratus and fog lingers over most of the region. Conditions should improve tonight, as fog and low level clouds mix out. Mostly cloudy skies are expected tomorrow morning, though VFR is expected through the day, as skies gradually clear. Clouds increase tomorrow night as a storm system arrives from the west. Long Term...Waves of low pressure brings a period of a wintry mix late Saturday into Saturday night with rain continuing through Sunday. Periods of IFR to LIFR will be possible late Saturday through Sunday. Some improvement is possible Sunday afternoon before the next system crosses New England Sunday night into Monday. && .MARINE... Short Term...SCA winds and seas will continue this afternoon. Winds will be out of the southwest at 15-30kts, slowly shifting to westerlies tomorrow morning. Winds will slacken to 8-14kts tomorrow, with seas around 3-6ft. Tomorrow night, winds shift to southerlies, with seas lowering to 2-4ft by Saturday morning. Long Term...Waves of low pressure will track across New England this weekend with winds and seas approaching SCA thresholds Saturday night into Sunday. Winds will drop below 25 kts Sunday night while seas remain elevated into Monday. A cold front will pass the waters Monday, with a compact area of low pressure advancing towards the waters from the west Tuesday. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...Small Craft Advisory until 8 AM EDT Friday for ANZ150>154. && $$ NEAR TERM...Tubbs SHORT TERM...Palmer LONG TERM...Cornwell