


Area Forecast Discussion
Issued by NWS Portland, ME
Issued by NWS Portland, ME
376 FXUS61 KGYX 151756 AFDGYX Area Forecast Discussion National Weather Service Gray ME 156 PM EDT Wed Oct 15 2025 .SYNOPSIS... High pressure over the Great Lakes will slowly move east through the end of the week while an upper low over the Canadian Maritimes may spread some showers into the area Thursday. High pressure moves closer to overhead Friday before settling south of New England this weekend starting a warming trend. A frontal system approaches early next week bringing the next chance for rain early next week. An upper low looks to hang around through the middle of next week, keeping the weather unsettled. && .NEAR TERM /THROUGH TONIGHT/... CAA continues overnight and will keep the boundary layer mixed enough for some northwest breeze to linger thru the night. With wind stirring the low levels I have neither frost nor fog in the forecast. But the CAA will allow temps to fall into the 30s and maybe even some upper 20s in the northern valleys anyway. More interesting for some will be the forecast in the western ME mtns late tonight into early Thu. As temps continue to fall an area of low level moisture will spill into the North Woods down to the upper Kennebec River Valley. Lift will be primarily driven by upslope...but forecast soundings are mostly saturated below freezing and thru the snow growth zone. So do not be surprised to see a few flakes falling from the sky in the early morning darkness. && .SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/... Thu will be another gusty day with northwest CAA continuing. Bufkit forecast soundings show mixing heights reaching into the low level wind max around 30 to 35 kt...especially south of the mtns. I feel pretty comfortable that frequent gusts in the upper 20s to low 30s kt will be observed Thu so I bumped up the NBM forecast with some of the 90th percentile guidance and the 15.12z HRRR. It will also feel rather chilly in those winds...with highs staying the 40s and 50s. With high pressure exerting more control over the region winds will drop soon after sunset Thu. Temps will again be in the 30s with pockets of upper 20s...so I expect some patchy frost but not enough confidence for an advisory for zones that are still active. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... Pattern Overview: A ridge builds in behind a departing upper low bringing a stretch of dry weather for the end of the work week and through the weekend. The next feature of note, will be vertically stacked low pressure moving through the area early next week. Models suggest this low may cutoff and hang around, keeping the pattern unsettled through the middle of next week. Impacts and Key Messages: * Temperatures trend above normal through the weekend * While too early to resolve specific details, a notable disturbance looks to arrive early next week. Details: Friday: Vertically stacked low pressure departs to the east Friday and with high pressure on its heels a tight gradient will remain through the morning hours, particularly on the coast where gusts 25-30 mph likely continue. The pressure gradient will be easing through the day with noticeably calmer conditions by the evening. A ridge building in at 500mb clears the sky and allows temperatures to warm into the upper 50s to low 60s south of the mountains, and into the low to mid-50s to the north. Winds eventually calm overnight, allowing temperatures to fall into the mid-to upper 20s north of the mountains, and into the low to mid 30s through the foothills. Closer to the coast a breeze may hang on keeping those locations in the upper 30s to low 40s. Saturday and Sunday: A ridge looks to be firmly in place over the region through the weekend. This continues the mostly clear skies and also the warming trend. Southwesterly flow at 850mb warms the airmass to around +6-8C Saturday, peaking on Sunday at around 10C. This should equate to surface temperatures in the low to mid-60s south of the mountains, and in the upper 50s to low 60s to the north on Saturday, with Sunday featuring temperatures in the mid- to upper 60s south and in the low to mid-60s north. This warmer airmass keeps low temperatures in the mid- to upper 30s Saturday night, with low 40s hanging on at the coastline. Clouds begin to build in Sunday evening as a potent trough approaches the region. This likely results in low temperatures only falling into the low to mid 40s areawide, with some upper 40s in portions of the coastal plain. Monday-Wednesday: Taking an early look at next weeks system, there are a couple things to note. The spread in the location of the low pressure center is large in the ensembles and this is resulting in about a 24-hr difference in precipitation arrival in the deterministics. The GFS breaks up the event racing a front through on Monday, with the secondary coastal low developing much later toward midweek. This would be an initially drier solution, with the slug coming later and overall with more QPF. The Euro has more support for the initial trough cutting off and becoming a vertically stacked low over the Delmarva Peninsula, as well as a secondary inside running low. This would be the slower solution with precipitation holding off until Tuesday. The two lows phase, but the Euro favors a weaker system overall and is drier. However, the second thing to note here is that we are not exactly talking about a soaker. Ensemble probabilities for greater than an inch are quite low in the GFS and Euro suite (30-50%), with LREF 25th-75th percentile differences around 0.75-1". Long story short, we will have to wait for better agreement to sort out the details, but with all signs pointing toward some form of an upper low hanging over the region, we are looking at a dreary start to next week. && .AVIATION /17Z WEDNESDAY THROUGH SUNDAY/... Short Term...Largely VFR conditions expected from here on out. Surface wind gusts around 25 to 30 kt will continue into the evening before diminishing to a steady northwest breeze overnight. Gusts pick up again Thu and will once again be near 30 kt at times. Will have to watch for some MVFR CIGs backing into the Midcoast region...but at this moment I keep the forecast VFR. Winds diminish again Thu night. Long Term...VFR looks to be the dominant condition Friday through the weekend as high pressure settles over the region. Wind gusts remain breezy with coastal terminals around 20-25kts and inland terminals around 15-20kts. Wind gusts should relax around 00Z Saturday. Ceilings thicken and lower Sunday night as a disturbance approaches the region. && .MARINE... Short Term...Gusty winds have arrived behind the cold front and will continue thru Thu night. A period of marginal gale force wind gusts is anticipated beginning Thu afternoon into Thu night...so gale watches have been converted to gale warnings. The SCA in the bays has also been extended thru Thu night. Long Term...SCA conditions last through at least the day Saturday. Wind gusts fall below 25kts Friday afternoon, but wave heights continue to hover around 5ft. We may get a brief period of sub-SCA conditions Sunday, but seas will quickly build back to around 5ft during the day Monday. These wave heights along with wind gusts 20- 25kts, look to stick around through the middle of next week as low pressure passes over the waters. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...Gale Warning from 2 PM Thursday to 8 AM EDT Friday for ANZ150- 152-154. Small Craft Advisory until 8 AM EDT Friday for ANZ151-153. && $$ NEAR/SHORT TERM...Legro LONG TERM...Baron