281 FXUS61 KGYX 050246 AAA AFDGYX Area Forecast Discussion...UPDATED National Weather Service Gray ME 1046 PM EDT Wed Jun 4 2025 .SYNOPSIS... Heat and humidity builds Thursday ahead of a slow moving cold front that will bring scattered showers and storms Thursday afternoon and evening, a few of which could be strong to severe. The front will linger near New England Friday into the weekend with waves of low pressure bringing daily chances for showers and storms. High pressure briefly builds in early next week. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... Update...Minor changes to reflect latest observational trends. Previous discussion...The rest of the day is a basically a what you see is what you get forecast. Warm/hazy conditions will continue with filtered sunshine from the elevated wildfire smoke. For tonight, the increased dewpoints will keep temperatures mild and mostly in the 50s and low 60s in some places. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/... The outlook for Thursday continues to be a hot one. We`ll continue to see mostly sunny into early afternoon with dry air and the upper ridge more or less still in place. There could still be lingering elevated wildfire smoke, but it`s modeled to not be as pronounced as today. Good mixing and even warmer air aloft will allow temperatures to climb higher than those of today with 850mb temps of +16 to +19C, which supports highs reaching the upper 80s to low 90s away from the coast. With dewpoints climbing into the lower 60s over much of the area ahead of a slow-moving cold front, it will feel more humid out with heat index values forecast to reach the low-mid 90s. As the front continues its approach, the ridge still start losing its grip in the afternoon over the area, especially toward the foothills and mountains. With increasing lift from the front, we should start seeing showers and thunderstorms develop during the afternoon and into the early evening hours. Instability is favorable for a few strong to severe storms with hail and damaging winds as the main hazards with mean MUCAPE from the HREF coming in around 1000-1500 J/kg. Wind shear is a little more marginal at 25 to 30 kt in the 0-6km layer, and there are a couple of other potential limiting factors. Mid-level lapse rates don`t look particularly favorable, and dry air aloft may also limiting coverage...which is what a lot of the 12Z CAMs seem to hinting at. However, the trade off with the dry air is that it increases DCAPE and the potential for strong to damaging wind gusts in any robust updrafts that get going. Farther to the south and toward the coast, forecast soundings are showing quite a bit of dry air aloft as well as a small temperature inversion, which is expected to keep chances lower, especially near the coast where the seabreeze will probably add even more stability. Showers/storms will then taper off through the evening, but there will be a continued low chance of showers overnight (20%) along with patchy fog. Overnight lows remain very mild and in the 50s and 60s. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... Friday starts off unsettled and warm. Highs in the upper 70s and lower 80s are likely as ridging remains overhead. Upper-level divergence and a mid-level shortwave should allow for a surface low to develop and move northeast Friday night and into Saturday. A few thunderstorms are likely Friday afternoon, as warm temperatures help build instability. A band of MUCAPE in the range of 700-1200 J/kg, and a little bit of wind shear could help develop showers and storms, though the severe threat remains limited. However, PWATs exceeding 1.5 inches could allow for these storms to produce efficient rain rates, plus the lack of directional wind shear may allow for some storms to train, potentially bring prolonged heavy rain, and localized minor flash flooding to a few. In addition, the WPC has issued a day 3 marginal risk Excessive Rainfall Outlook for much of western New Hampshire. There is some uncertainty on a specific track, but the general model consensus has a rain axis pivoting over central NH and Maine by Saturday morning. Steadier rain may continue through the day Saturday. It should be a little cooler, with Saturday`s highs expected to be in the 60s and low 70s. By Sunday, some lingering showers are possible earlier on as the front progresses offshore. Any of these remaining showers should clear the area in the afternoon. A dry Monday looks likely as ridging quickly builds back into the region. Another shortwave arrives towards the middle of next week, with more widespread rain possible Tuesday and Wednesday. The end of next week looks drier, though a low may try to move in over next weekend. Next week`s temperatures look to be in the 70s through much of the week. && .AVIATION /03Z THURSDAY THROUGH MONDAY/... Short Term...Mainly VFR through Thursday, although there may be a bit of fog or low stratus late tonight into Thursday morning with potential looking too low for TAF inclusion. Otherwise, a cold front brings increasing chances for showers and storms Thursday afternoon and evening which could bring TEMPO IFR restrictions should they pass over a terminal. These should diminish through Thursday evening, but then there may be fog or low stratus to contend with Thursday night. Long Term... MVFR expected Friday morning, with LIFR likely with patchy fog along the coast. Restrictions lower Friday afternoon as thunderstorms develop across the northeast. Restrictions are expected to stay down through Saturday evening at least, as steady rain and thunderstorms move through the area. Restrictions may improve for Sunday and Monday, as showers and storms become increasingly more isolated. && .MARINE... Short Term...Southerly flow continues through Thursday with conditions remain below SCA levels but may brief switch to more westerly overnight and into early Thursday morning. A cold front approaches from the north and west late in the afternoon and evening on Thursday, and ahead of this front, fog may return over the waters along with a chance of showers and a couple of storms. Fog likely lingers into Thursday night. Long Term... Variable winds at near 10-15kts expected through the weekend and into early next week. 1-3ft seas expected Friday and Saturday. Seas gradually increase on Sunday, seas may reach SCA levels over the open waters along the Midcoast Sunday afternoon. Seas gradually diminish afterwards, through the first half of next week. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...Air Quality Alert until 11 PM EDT Thursday for MEZ023>028. NH...Air Quality Alert until midnight EDT tonight for NHZ013. Air Quality Alert until midnight EDT Thursday night for NHZ014. MARINE...None. && $$ NEAR TERM...Legro SHORT TERM...Combs LONG TERM...Palmer