


Area Forecast Discussion
Issued by NWS Caribou, ME
Issued by NWS Caribou, ME
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994 FXUS61 KCAR 302332 AFDCAR Area Forecast Discussion National Weather Service Caribou ME 732 PM EDT Mon Jun 30 2025 .SYNOPSIS... A cold front will approach tonight and cross the area Tuesday. A disturbance will cross the region Wednesday. Another disturbance and cold front will cross the region Thursday. An upper level low will cross the region Friday. High pressure returns Saturday. && .NEAR TERM /THROUGH WEDNESDAY/... 730 pm update... Areas of fog moving north over the waters with Nantucket down to 1/4 mile at this time. Expect this will head onto the Downeast coast by 06z and have changed patchy fog to areas of fog over the waters and along the coast late tonight, and have spread fog inland toward Bangor right around sunrise. Will be monitoring for Dense Fog Advisory late tonight. Otherwise no major changes needed to forecast this evening. Prev discussion blo... The mid level and surface ridge will move off to the east tonight as the vertically stacked trof moves east across the Great Lakes. For this evening and tonight, clear skies and cooler S flow will bring temps into the 60s across the region with 50s along the coast. Clouds will begin to increase as the cold front moves closer to the area. As RH increases throughout the night. Patchy fog is expected to develop in low terrain. For Tuesday, the warm from to the north will continue to influence the S flow and the cold front will approach from the west. High res models indicate that the initial rain showers will move into the region in the late morning to early afternoon starting in the west and progressing E. Upper air model soundings show some instability with the higher CAPE values in the North Woods. Lapse rates continue to be weak across the region. As of this update, the bulk wind shear is in a favorable set up, thus thunderstorms are expected to develop with better chances in the North Woods. The PWATS are showing higher amounts across the models, so heavy downpours are a concern with any of these pulse thunderstorms. For Tuesday night, the NBM does well with keeping the showers around across the south as the cold front exits to the E. Though the SREF does not show the strongest signature for possible low level moisture, the slowly clearing skies and cooling temps indicate possible patchy to areas of fog. && .SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY/... A narrow ridge of high pressure will build in behind the frontal passage, leading to mostly drier weather on Wednesday. Southerly return flow on the backside of this ridge will help feed mid level moisture into the area that could support some diurnally driven showers and thunderstorms Wednesday afternoon, mostly across the north. Warm weather continues with temperatures lifting into the low to mid 80s. The next low pressure system will approach the area from the west on Thursday. A deepening low across Quebec will be the parent low to a cold front sweeping through northern New England. There is increasing confidence that the FROPA timing for our forecast area will be sometime mid to late Thursday afternoon, which will coincide with peak diurnal heating. With this forcing and lift in place, along with the instability that the front will bring, there exists a chance for thunderstorms across nearly the entire forecast area. The exception will be along the immediate coast, where the stable marine layer will neutralize any convective potential due to the onshore flow. With deepening cold pool aloft and inverted V presentation on forecast soundings, there could be a threat for stronger wind gusts in any thunderstorms that do develop. Bulk shear is also forecast to be at least 30 kts through this time, further supporting the potential for possibly some more organized thunderstorms. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... The main vort max of the synoptic low pressure system will likely move over the state Thursday night into Friday. The 12z GFS suggests that the vort max may cross northern Maine with peak vorticity along the eastern Maine border. The 12z CMC agrees with this outlook, with the 00z ECMWF in line as well, though resolving a deeper trough aloft. With the center of this low crossing the forecast area, a cold pool aloft will act to further destabilize the environment and could lead to another round of thunderstorms which accompany the precip that moves in with the low. Lapse rates will steepen, and enough CAPE and shear could be present to support some storm organization. With colder air moving in aloft and the potential for moderate bulk shear, these storms may even support hail development into Friday afternoon and evening, and this setup will continue to be closely monitored over the next several days. High pressure will follow behind this system, leading to drier weather into the weekend, while temperatures rebound towards average behind the recent low pressure. Another shortwave could make its way through the area Sunday into Monday, though guidance is more uncertain this far out. && .AVIATION /23Z MONDAY THROUGH SATURDAY/... NEAR TERM: Downeast terminals starting off VFR this evening before BHB drops quickly to IFR after 04z and eventually VLIFR between 06 and 15z with 1/4SM in FG and VV001 cigs expected. BGR looks to diminish to 3/4SM and BKN002 between 09 and 15z. Both terminals very slowly improve after late morning with VCSH expected. Aroostook terminals VFR through morning into the early afternoon before dropping to MVFR cigs after 17z. FVE and CAR may diminish to IFR cigs after 18z with all terminals seeing hit and miss showers. TSTMS may be possible but confidence is extremely low and have not included mention in forecast at this time. SHORT TERM: Wed...Generally VFR across all terminals. A chance of showers and thunderstorms in the afternoon, mostly at northern terminals. WSW winds 5 to 10 kts with gusts up to 20 kts in the afternoon. Wed night...VFR with SKC. Winds light and variable. Thursday...VFR cigs in the morning, becoming MVFR/IFR as rain moves in from NW to SE. Chance for afternoon/evening thunderstorms at all terminals aside from the immediate coast. SW winds 5 to 10 kts. Thurs night...Occasional IFR early. Otherwise, mostly VFR. Rain showers quickly diminishing through the night. Light W winds. Fri - Fri night...Mainly VFR across all terminals, trending towards MVFR/IFR in any rain showers or thunderstorms. NW winds 5 to 10 kts. Sat...VFR across all terminals. W winds 5 to 10 kts. && .MARINE... NEAR TERM: Winds and seas will remain below SCA conditions tonight. A few gusts up to 25 kts possible on Tuesday afternoon. Seas 2-3 ft. Areas of fog expected to reduce visibilities late tonight. SHORT TERM: Winds and seas will likely remain below small craft advisory criteria Wednesday through the end of the week. Rain showers and a few thunderstorms possible by the end of the week. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...None. MARINE...None. && $$ Near Term...LaFlash Short Term...AStrauser Long Term...AStrauser Aviation...LaFlash/AStrauser Marine...LaFlash/AStrauser