Area Forecast Discussion
Issued by NWS Portland, ME
Issued by NWS Portland, ME
111 FXUS61 KGYX 191822 AFDGYX Area Forecast Discussion National Weather Service Gray ME 122 PM EST Wed Nov 19 2025 .SYNOPSIS... High pressure continues to build into the region this afternoon under a mostly sunny sky and near normal temperatures. However, tonight`s temperatures should drop quickly given a clear sky and light winds. By Thursday morning expect widespread temperatures in the teens and 20s with a few single digit readings even possible across the northern valleys. A cold front will cross the area to end the work week, bringing mostly rain showers but some mountain snows. && .NEAR TERM /THROUGH TONIGHT/... With most of New England under the influence of deamplifying northwest flow aloft and surface high pressure moving in from the west, the near term continues to look very quiet. Highs this afternoon will generally be around normal for this time of year, ranging from the 20s and 30s north and over the mountains, to the low to mid 40s elsewhere. Expect plenty of sunshine and generally light winds with the high pressure influence. Light winds continue tonight under a clear sky overhead. Conditions will be very favorable for radiational cooling and a cold night. For lows, the decision was made to blend in the NBM 10th percentile to the previous forecast to better capture this signal. Expect widespread readings in the lower teens to lower 20s with a few single digits possible over some of the northern valleys. Last night saw some Connecticut River Valley fog so formation is not out of the question again tonight and added some mention of patchy fog here. && .SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/... The short term also looks fairly quiet as we slowly transition to near zonal flow aloft on Thursday and then back into southwest flow aloft by Thursday night. Thursday`s highs should be similar to today, but we may be a touch warmer over the higher terrain. Winds will remain very light but should start to increase out of the southwest over the coastal waters by late Thursday night. Cloud cover will also start to increase Thursday night as the next longwave trough moves closer and we transition into southwest flow aloft. As of now, it looks like precipitation should hold off until after the short term period. Lows Thursday night will not be as cold but still pretty chilly, mainly in the upper teens to upper 20s. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... Key Messages: * Friday/Friday night system is struggling with lack of moisture needed for a more widespread wetting precip event. Details: Occluded low over Hudson Bay will push a frontal feature towards northern New England Friday. This will bring precipitation to the area, but timing has continued to trend slower. Would expect expanding and thickening clouds to bring precip to the higher elevations first, gradually filling into the mtn valleys into the afternoon. Downsloping will further erode what moisture accompanies the front, and QPF outside of the mtns and foothills is light, perhaps more showery. Southern moisture remains a non-factor as a train of zonal lows across the OH/TN Valley keeps much of this suppressed to the south. Where guidance earlier this week attempted to phase these two systems, this now looks to take place during or after the occluded front pushes through the forecast area. Thus thoughts yesterday still hold true with the most precip in the mountains and drying bringing less QPF to the coast and interior. There are some solutions that bring a second plume of rain into the Gulf of Maine by Saturday morning, clipping southern NH and the southern ME coast. However, still equal chances this occurs later and over the open Gulf waters. For precip types, model soundings point to a rain/snow event with rain in most locations and snow mixing in for the mountains. Brief high pressure works into the region Saturday night with clouds remaining mostly over the mountains. Drying in the column increases confidence that other locations see mostly clear skies. Did drop low temperatures for another cool night in the lower 20s and upper teens. This should be attainable in good radiational cooling conditions. Hesitant to go any lower with center of the high to the south and light NW breeze continuing in the evening. Will look for another weak disturbance to swing through northern New England Sunday night followed by another brief ridge of high pressure through early week. Next system to impact the region with measurable precip looks to be into mid-week next week. Early deterministic runs, and AI-GEFS, portray this as a overunning event with additional low development in the Gulf of Maine. This could lead to CAD and mixed precip, but duration and intensity will need to be refined as the date nears. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... Short Term...Largely VFR conditions are expected through Thursday. There could be some patchy fog tonight over the Connecticut River Valley which may impact LEB, but confidence is not high enough to include mention for the site specific TAF. Any fog that does form should lift by early to mid Thursday morning. Long Term...Clouds thicken and lower Friday morning with MVFR ceilings overtaking the area through the afternoon and evening. Its possible coastal terminals see only periods of MVFR, where greater confidence of these lower ceilings is further inland and into the mountains. Still could see period of IFR ceilings for mountain/western terminals overnight. SHRA is forecast for much of the area, most prominent to again where MVFR is likely. SHSN may reduce some vis in the mountains. Expect trend to VFR for Sat and Sun, with lowered ceilings holding on towards HIE and CAN/US border locations. && .MARINE... Short Term...Winds and seas will remain below SCA thresholds through Thursday. Long Term...Southerly flow preempts passage of a occluded front Friday night. These become NW Saturday with some gusts to 25 kt on the coastal waters. These slacken Sat night into Sunday as high pressure passes to the south. A weaker system passes to the north Sun night, with high pressure again building across the region Mon/Tues. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...None. && $$ NEAR TERM...Hargrove SHORT TERM...Hargrove LONG TERM...Cornwell AVIATION...Hargrove/Cornwell MARINE...Hargrove/Cornwell