


Area Forecast Discussion
Issued by NWS Portland, ME
Issued by NWS Portland, ME
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119 FXUS61 KGYX 162220 AFDGYX Area Forecast Discussion National Weather Service Gray ME 620 PM EDT Mon Jun 16 2025 .SYNOPSIS... Areas of fog along with some drizzle will make a repeat performance tonight, especially along the coast. Tuesday will be a much cooler and cloudier day with a few showers and drizzle at times. Conditions improve some Wednesday as the onshore flow turns more southerly. Warmer temperatures are expected along with a chance of late afternoon showers and thunderstorms. A cold front approaches on Thursday with higher chances for showers and thunderstorms. Friday and the weekend will be drier but a few showers or thunderstorms cannot be ruled out. && .NEAR TERM /THROUGH TONIGHT/... 620 PM Update...Just minor changes to temperatures and dewpoints to keep aligned with observations. The forecast remains on track with fog and drizzle expected to develop later tonight. Previous Discussion... Tonight will once again be cool and somewhat moist as easterly flow around offshore high pressure continues. This will likely mean the redevelopment of fog and perhaps some drizzle, especially on the coastal plain. Lows will mainly be in the 50s. && .SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/... Low level onshore flow and deep layer WAA continues on Tuesday. This should set the stage for a less than stellar day with plenty of clouds along with a few light showers and drizzle. Lowered high temperatures a good 5-10 degrees south and east of the mountains as clouds and low level easterly flow will cap temperatures. A few rounds of showers and possibly a few thunderstorms are expected Tuesday night as the WAA pattern strengthens. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... Wednesday morning will start out cloudy for much of the area with some fog/drizzle and a few showers mixed in. Fog should lift through mid-morning, except lasting a little longer along the coast, and then forecast soundings suggest mixing out the low clouds with partly sunny skies going into the afternoon. A low pressure passing to the north will leave a weak front draped across the area, which will aid in scattered showers developing in the afternoon, mostly in the mountains, along with a few storms. These will mostly fizzle out in the evening, and then based on the light southerly flow continuing, will probably see a return of fog and low stratus overnight that lingers into Thursday morning. A more potent cold front approaches on Thursday, and once the low clouds and fog lift in the morning, it looks to be a hot day with temperatures away from the coast reaching the mid 80s to low 90s based on sounding profiles, perhaps mid 90s in NH. This front will bring a chance of showers and storms to the area, with the highest chances being across western and northern locations at this time, and some storms have the potential to be strong to severe depending on the timing of the front. There are lesser chances of storms to the south and east of the I-95 corridor where the seabreeze is more likely to bring in the more stable marine layer. The cold front quickly passes Thursday night with it becoming breezy either late Thursday night or Friday morning and then continuing during the day Friday. At this point in time, I have trended the forecast higher than the NBM on wind gusts, but these may need to be bumped up more in the future. Forecast soundings suggest 30-40 mph, but there may be a window where gusts could top out in the 40-50 mph range, per the top of the mixed layer. High temperatures will come down from those of Thursday, but still expecting it to be warm with highs in the 70s to lower 80s. A 500mb high becomes centered over the southeast US with the ridge axis extending northward across the Great Lakes on Saturday and then across much of the eastern US by Sunday. While this will bring generally dry weather here, it doesn`t mean that the weekend will be completely dry as being on the eastern periphery of an upper ridge can sometimes bring waves in on the northwest flow. The operational GFS/ECMWF are latching onto a shortwave in what almost would resemble an MCS sometime over the weekend, but there is much disagreement on the timing and location of the wave this far out other than the possibility is there. Going into early next week, there is a growing signal in the global models for a strong ridge of high pressure to further expand over the eastern CONUS. Whether or not it extends far enough north into New England to keep any waves in the west to northwest flow and precip chances north of the area remains to be seen, but there is more confidence in bringing in very warm to hot conditions. With the 850mb temperatures being advertised, highs could get into the 80s to low 90s Monday and then possibly hotter just beyond the end of the forecast period. && .AVIATION /22Z MONDAY THROUGH SATURDAY/... Short Term...VFR is expected this evening but areas of IFR or lower are expected again tonight in marine fog and stratus. Some of this may burn off Tuesday but it will be tougher to do so with deeper low level moisture in place. Thinking IFR will be present most of the day on the coastal plain. IFR everywhere Tuesday night with showers and CHC thunder. Long Term...Quite a few opportunities for flight restrictions Wednesday through Friday. Wednesday morning could feature some lingering showers but more likely IFR to LIFR stratus as well as fog. Conditions improve through the afternoon, but there will be additional chances for showers and a few storms. A similar story is expected Wednesday night into Thursday morning with LIFR to IFR conditions with low stratus and fog possible with improvement during the day. A cold front does approach and brings another chance of showers and storms during the day Thursday evening and then diminishing in the evening. Behind the front, sites with any restrictions will return to VFR with west winds picking up Thursday night into Friday with some potential for gusts 30-35 kt. Mainly VFR Friday through Saturday with a few showers possible Friday afternoon. && .MARINE... Short Term...Fair conditions thru Tue night under high pressure. Areas of fog will be possible near the coastline this morning and again tonight. Small craft conditions are not expected in the short term but a few 20-23 kt gusts will be possible Tue night on the ocean waters. Long Term...Southerly flow continues Wednesday (below SCA levels) with high pressure to the east and low pressure passing to the north. A cold front then approaches Thursday and crosses later in the day or Thursday night and may reach SCA criteria that last through portions of Friday. Another weak front may cross on Friday before high pressure builds in south of the waters to start the weekend, offering improving conditions. Another weak low may approach the waters around Sunday. Also expect fog to continue at times over the waters through Thursday or Thursday night until the front passes. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...None. && $$ NEAR TERM...Baron/Ekster SHORT TERM...Ekster LONG TERM...Combs