


Area Forecast Discussion
Issued by NWS Caribou, ME
Issued by NWS Caribou, ME
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260 FXUS61 KCAR 160135 AFDCAR Area Forecast Discussion National Weather Service Caribou ME 935 PM EDT Sun Jun 15 2025 .SYNOPSIS... High pressure will slide east of the area Monday into Tuesday. Low pressure will then pass northwest of the area Wednesday dragging a warm front northward by Thursday morning. A cold front will cross the area Thursday night. A large area of high pressure will set up across the Eastern Seaboard on Friday. && .NEAR TERM /THROUGH MONDAY/... 930pm Update... Just small tweaks to account for current conditions. Otherwise, forecast is on track. Main item of uncertainty is how quickly and to what extent fog will form. Kept with the idea of patchy fog developing toward midnight Downeast and the coast, and toward sunrise in some inland valleys. Previous Discussion... A weak disturbance could touch off some isolated showers this afternoon from the Central Highlands into eastern Aroostook and northern Washington counties. Otherwise, high pressure will dominate the weather through tonight. Any convective cumulus clouds will dissipate this evening with the loss of daytime heating. Mostly clear skies and nearly calm winds will provide favorable conditions for radiational cooling from the Central Highlands northward. Thus, went below NBM guidance for low temperatures tonight in these areas, particularly in colder valleys. This will result mostly in lows in the lower to mid 40s, but some 30s will be possible in the coldest spots. Not expecting frost development, but could see some patchy river valley fog towards daybreak. Weak onshore flow tonight will provide some more clouds and patchy fog for the Bangor region and Downeast. Lows there tonight will be in the mid to upper 40s. Surface high begins to slide east on Monday, setting up return flow from the south and southwest. Ample sunshine in the morning will give way to some clouds in the afternoon. Winds will be more southwesterly from the Central Highlands northward Monday. This is downslope direction there, so went a bit above NBM guidance there. Expect highs in the mid to upper 70s in these areas. The wind direction near Bangor and Downeast will be more southerly. This will bring in some cooler air from the Gulf of Maine. Highs will be in the lower 70s for Bangor and Interior Downeast, with 60s for Coastal Downeast. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... Mon night expect the high to continue to drift S of Nova Scotia with return flow over Maine and increasing boundary layer moisture. Expecting areas of fog to push in from the Gulf of Maine waters into the Downeast coast up to Bangor. Otherwise valley fog is possible from much of the rest of the area. Generally less than 5mph S winds. Expecting lows to fall back into the low 50s for most locations by Tue AM. Tue features increasing S flow over the area which will make for a strong seabreeze Downeast pushing N of the Route 9 corridor. Expect highs to top out there in the 50s and 60s with around 70F along Route 9. Warmest temperatures will be from the Central Highlands, Upper Penobscot Valley northward to the St. John Valley with upper 70s to near 80F. Breezy S winds 10-20mph. A weak open shortwave at 500mb may kick off a few afternoon showers mainly in western zones from Moosehead northward and cannot rule out a few lightning strikes along the Quebec border. Tue night as the shortwave pivots northward over Maine expecting a chance of showers going all night. Moist boundary layer means fog will be possible as well especially Downeast where it could be dense again. Temperatures remain mild in the upper 50s except low 50s near the Washington County coast where the wind is off the colder near Bay of Fundy waters. A weak surface trof will shift winds more SSW-SW by daybreak Wed. Wed looking slightly warmer under partly sunny skies and warmer 925mb temps working in. Solid agreement in the latest suite of global models showing +17C to +19C over the area. Highs 1-3 degrees warmer than Tue with widespread upper 70s to low 80s. Coolest spots will be from Ellsworth eastward thanks to the seabreeze. A weak shortwave will provide a kick for afternoon showers and potentially a few thunderstorms. Latest GFS, ECMWF, and Canadian keep the MUCAPE 500-1000j/kg in the Central Highlands to S. Aroostook northward. Will continue the mention of a slight chance of thunder with these showers and just a few showers south of these locations. Potential exists for some heavy rain in any showers and storms that develop with PWATs approaching 1.5 inch which is 1.5-2 sigma. Will need to continue to monitor trends in operational runs and ensembles as sometimes these global models struggle with producing more robust CAPE values in New England. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... Wed night into Thu AM a warm front will lift north through Maine with a surface low tracking from NY state into Quebec. A lot of clouds and fog with a nearly saturated boundary layer expected and light and variable winds. Warm night with lows in the 58-62F range by Thu AM. Thurs fog will mix out in the morning as S winds increase with winds slowly shifting SSW to SW in the afternoon as a cold front approaches from the NW. The GFS and GEM are generally producing 500-1200j/kg of CAPE with ECMWF up 1000-2000j/kg of CAPE. PArtly sunny skies will quickly allow heating to reach convective temperatures by late morning to midday ahead of the cold front. Several ensemble members suggesting a prefrontal trof will be the kicker to develop storms but timing vary on this which means instability is in question. Confidence is high enough to go likely POPs for northern 1/2-2/3 of the CWA with chance thunder at this point. Shearing looks decent at 30-40kt, if instability builds to ECMWF levels we may be looking at a severe weather day since the ingredient will be there. Need to monitor the trends. Cold front pushes through Thu night but upper level energy remains overhead to keep shower chances going. A ton of uncertainty in the long term from Fri onward with numerous solutions keeping the pattern progressive while the GFS operational cuts off a low overhead and keep high probability of showers going into next weekend. The latest NBM is closer in line with the ECMWF and keep chance of showers with a more progressive pattern and not a total washout from Fri into next weekend. Temperatures generally remain seasonable to slightly above normal but no widespread heat and humidity expected at this point. && .AVIATION /02Z MONDAY THROUGH FRIDAY/... NEAR TERM: Tonight... From HUL North...Vast majority of places will be VFR, but can`t totally rule brief IFR fog at HUL and PQI late tonight. Not nearly enough confidence in this to put into TAF. Slight breeze late this afternoon will slacken quickly as the sun sets. BGR/BHB...IFR/lower possible later tonight after about 6z. That said, not totally convinced the low ceilings and fog will develop, especially for BGR. Give BGR about a 50 percent possibility of IFR and 75 percent possibility of MVFR. Give BHB about a 75 possibility of IFR or lower. S breeze around 10 kts late this afternoon with dissipate this evening. Monday... Morning fog should quickly go away, leaving way for a VFR day. SW wind around 10 kts in the afternoon. Can`t rule out an isolated shower in the afternoon N of BGR, but even if any showers does impact a TAF site, not anticipating anything less than VFR. SHORT TERM: Tue...AM IFR/LIFR possible due to BR/FG at southern terms. BCFG/BR may reduce vsby at northern terms. VFR for the day. S-SSW winds 5-15kt with gusts up to 20kt. PM VCSH at FVE, CAR and PQI possible. SHORT TERM: Wed...AM IFR/LIFR possible due to BR/FG at southern terms. BCFG/BR may reduce vsby at northern terms. VFR with building cigs midday. CB likely afternoon. Afternoon VCSH/VCTS at BGR and all northern terms. VCSH at BHB. S-SW winds 5-15kt. Thu...AM IFR/LIFR possible due to BR/FG at southern terms. BCFG/BR may reduce vsby at northern terms. CB likely afternoon. Afternoon -SHRA/TS likely at BGR and all northern terms. VCSH/-SHRA possible at BHB. S winds 5-15kt. LLWS possible. Fri...VFR. Brief vsby/cig reduced with VCSH/VCTS in the afternoon all terms. NW winds 5-15kt. && .MARINE... NEAR TERM: Winds and seas will remain well below Small Craft Advisory criteria through tonight and through Monday. Fog will reduce visibility on the waters at times late tonight into Monday. SHORT TERM: Winds/seas expected to remain below SCA conditions throughout this week. Seas 1-3ft Tue-Thu then 2-5ft on Fri. Winds generally less than 22kt this week. S winds Tue, SW on Wed, S on Thu and W-NW on Fri. Fog will reduce vsby less than 1NM at times from Tue-Thu and potentially again Fri. Showers possible Wed-Fri. Sea surface water temperatures from the Hancock County coast out 25nm including Penobscot Bay ranges from 48-51F this week. Water temperatures from the Washington County coast out 25nm and east to the Hague Line including Passamaquoddy Bay range from 45-49F this week. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...None. MARINE...None. && $$ Near Term...Foisy/Clark Short Term...Sinko Long Term...Sinko Aviation...Foisy/Clark/Sinko Marine...Foisy/Clark/Sinko