


Area Forecast Discussion
Issued by NWS Portland, ME
Issued by NWS Portland, ME
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095 FXUS61 KGYX 041352 AFDGYX Area Forecast Discussion National Weather Service Gray ME 952 AM EDT Fri Apr 4 2025 .SYNOPSIS... Today will be a pretty typical spring day across the forecast area. Temperatures will be warm but it will be breezy and drier. This will be short lived however, as the next storm will be approaching Saturday. Precipitation overspreads the area during the second half of the day. Some snow is possible, but most likely it will be a wintry mix followed by a transition to rain. The weather pattern will remain active into next week, with additional chances for wintry weather. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 950am Update...Upper cloud cast is quickly moving east across the forecast area at this hour. This should give way to a mostly sunny day along the coast and interior with clouds lingering in the mountains. Expect breeze to pick up as well as temps to jump w/ more direct sunlight. Will next focus on weekend event which will bring mixed precip to the area. Ensemble guidance has trended less confident in total amounts greater than half an inch through Sunday morning. Will be looking to perhaps include periods of drizzle between segments of QPF Saturday and Saturday night. 630am Update...Minor changes to reflect latest observational trends. Previous discussion...Lingering fog near the coast is gradually mixing out as a cold front slowly works thru the region. Once the fog clears...besides some high clouds...it will be mostly sunny and warm today. A steady northwesterly breeze may make it feel slightly cooler than what the thermometer will read...but highs in the 50s to near 60 in the far south are likely today. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/... Tonight will be a quiet one...with the breeze lingering thru the first half of the night before becoming light and variable. The next storm system will be approaching with a warm front heading for northern New England. Opted for a non-diurnal temp trend Sat...as it will be warmer prior to precip onset. Once precip starts falling temps will wetbulb down into the low to mid 30s. My confidence is pretty low on exactly how cold it will get during the day...but temps will be near freezing and there is a threat of mixed precip again. This could be another case of a brief period of snow followed by sleet/freezing rain before ending as rain. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... 04Z Long Term Update... Latest forecast guidance including the latest NBM is hinting at a potentially longer period of sleet for areas even south of the mountains on Saturday evening and therefore incorporated this into the forecast. Otherwise, no major changes were made at this time. Previously... 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 /14Z FRIDAY THROUGH TUESDAY/... Short Term...IFR or lower conditions have become much more localized this morning as a cold front works thru the region. Fog and low CIGs are largely confined to the coast at this time...and will mix out with the front over the next hour or two. VFR conditions are then expected thru around Sat morning. Precip moves in with another warm front crossing the region later Sat. IFR or lower conditions are expected once again...with some mixed precip possible. Right now any mix is most likely in the far interior and higher terrain. 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...Wind gusts have diminished but it will remain breezy today as a cold front crosses the waters. Seas also continue to diminish...but north of Cape Elizabeth they will remain above 5 ft for several more hours. I have dropped the SCA for the bays and outer waters south of Cape Elizabeth. Winds will gradually become onshore again by Sat, increasing thru the day but remaining below SCA thresholds. 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...None. && $$ NEAR TERM...Cornwell/Legro SHORT TERM...Palmer LONG TERM...Cornwell/Tubbs