


Area Forecast Discussion
Issued by NWS Caribou, ME
Issued by NWS Caribou, ME
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301 FXUS61 KCAR 010948 CCA AFDCAR Area Forecast Discussion National Weather Service Caribou ME 434 AM EDT Tue Jul 1 2025 .SYNOPSIS... A cold front crosses Maine today. 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/... 4:30AM Update....Dense fog begins to move into coastal and Downeast regions this morning, with visibility around a quarter miles or less in areas. Exercise caution if commuting or traveling this morning. Visibility should begin to improve later this morning. Also updated forecast to remove thunder potential along the coastline, due to southerly flow bringing a stable marine layer over the area. Previous Discussion... Today, low pressure system to the northwest moves northeast, as the associated warm front sweeps through New England. Maine will be in the warm sector during the morning hours, helping raise temperatures back up into the mid- to-upper 70s. Coastal Maine areas will be in the upper-60s due to the southerly seabreeze, which helps to stabilize the area. Low winds, increasing relatively humidities, clear skies and inversion cause some fog to move into coastal and portions of Downeast Maine early this morning. Immediate coast will see some reduced visibility, with areas of fog, that is expected to lift up to low stratus going into the afternoon period. Westerly flow helps to keep fog generally around and south of I-95. With this low pressure system, there is a potential for some severe weather if convection is able to fire off. Favorable CAPE, CIN, shear, and helicity for thunderstorm development, most of which is confined to western North Woods and Central Highland region. Sea breeze along the coast keeps a stable marine layer over Downeast, so really not expecting convection down there at this time. Working against convection in the north is some pretty lack-luster lapse rates. Since most of the instability is elevated, some lifting mechanism would be needed in order to support parcel lifting. This could depend then on the speed of the associated cold front, or if the surface trough that may develop between the two fronts will be strong enough to get things moving. Current trends continue to show a slower solution to front movement, and surface troughs do not look too impressive. Main threats could be some heavy rainfall, as PWAT values range from 1.5-2 inches for most of the area. DCAPE values are not too impressive, but elevated winds aloft could result in some gusty winds as well if thunderstorm does develop. Tonight, cold front passes over Maine. Another humid night with light winds, so fog development could occur in coastal areas and valleys. Overnight lows generally in the 60s. During the day tomorrow, brief period of ridging occurs. Low pressure system from Tuesday moves east in the Atlantic, keeping associated rain showers to the waters. Approaching low to the northwest could cause some shortwave kinks in low-levels, and with increasing moisture, could be a few rain showers in the north tomorrow. Convective parameters do not look favorable for convection associated with these, as mid-level lapse rates are just not impressive. CAPE, CIN, and helicity are there, but nothing really standing out at this point. Maybe a brief period of showers. Daytime highs in the mid-80s. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... Brief ridging will occur Wednesday night with partly cloudy/mostly clear skies. A surface/upper low, along with a cold front, approach from Quebec province Thursday. Expect increasing shower/thunderstorm chances Thursday, most extensive across northern/central areas. The upper low will approach Thursday night, while the cold front begins to cross the region. Could still have the chance of a thunderstorm early Thursday night. Otherwise, generally expect partly cloudy skies along with a chance of showers. The upper low will cross the region Friday with a chance of showers/thunderstorms, with the better chances across northern and central areas. Steep lapse rates with the cold pool aloft could help support the risk of hail with any stronger thunderstorms. Expect slightly above normal level temperatures Thursday. Expect near normal, to slightly below normal, level temperatures Friday. && .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... The upper low will begin to exit Friday night. Could still have a slight chance/chance of showers early Friday night, with partly cloudy/mostly clear skies overnight. The upper low will exit across the Maritimes Saturday, though how rapidly this occurs is still uncertain. With the cold pool aloft still in the vicinity, steep lapse rates could still support a slight chance of showers Saturday, mostly across the north and mountains. Otherwise, expect partly cloudy/mostly clear skies Saturday. Uncertainty still exists regarding another potential system which could impact the region Sunday into Monday. Have included a chance of showers/thunderstorms Sunday into Monday due to the uncertainty. Near normal, to slightly above normal, level temperatures are expected Saturday. Slightly above normal level temperatures are expected Sunday/Monday. && .AVIATION /09Z TUESDAY THROUGH SATURDAY/... NEAR TERM: KFVE/KCAR/KPQI/KHUL: Generally VFR this morning, becoming MVFR/IFR today due to lowering ceilings and some rain showers. Slight chance for some thunderstorms this afternoon, but not enough confidence to include in the TAF. Winds generally from the S, at 5- 10 kts this morning, before becoming SW by this evening. Periods of gusty winds expected this afternoon at all northern terminals. KBGR/KBHB: KBGR currently VFR, but expected to go down quickly to IFR as fog is expected to settle into the area this morning. Fog will lift during the morning hours, but LIFR ceilings will prevails until afternoon. KBHB is forecast to drop visibility pretty fast, with some more dense fog expected along the coast. Ceilings and LIFR conditions forecast this morning into evening. Potential for some brief rain showers at KBGR this afternoon, and at KBHB this evening. Slight chance for some thunderstorms this afternoon, but not enough confidence to include in the TAF. Winds generally from the S today, at 5-10 kts. KBGR might get some gusts up to 20 kt this afternoon. Winds shift to the SW by tonight, with ceilings beginning to lift to at least IFR/MVFR. SHORT TERM: Wednesday night...VFR. Variable winds 5 to 10 knots. Thursday...VFR early, then MVFR/IFR with a chance of showers and thunderstorms. Variable winds 5 to 10 knots. Thursday night...Occasional IFR early. Otherwise, VFR/MVFR. A chance of showers. Chance of a thunderstorm early. West/southwest winds 5 to 10 knots, becoming west/northwest. Friday...Variable conditions with any showers or thunderstorms, Otherwise, VFR/MVFR. West/northwest winds around 10 knots. Friday night...Occasional MVFR early with a chance of showers. Otherwise, VFR. West/northwest winds 5 to 10 knots. Saturday...VFR. Slight chance of a shower north. West/southwest winds 5 to 10 knots. && .MARINE... NEAR TERM: Winds and seas below Small Craft Advisory criteria today and tomorrow. Seas stay at or below 4 ft over the outer waters, and at or below 3ft for the inner waters. Southerly winds today at 10-20 kts. Gusts generally around 20kt, with a few gusts up 25 kt possible. Winds shift SW by tonight, into Wednesday. Fog expected this morning, and late tonight. Potential for rain showers this afternoon into tomorrow. SHORT TERM: Winds/seas below small craft advisory levels Wednesday night through Friday. Slight chance of a shower/thunderstorm Thursday afternoon. A chance of showers Thursday night. Slight chance of a shower/thunderstorm Friday afternoon. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...Dense Fog Advisory until 10 AM EDT this morning for MEZ015>017- 029-030. MARINE...None. && $$ Near Term...Brennan Short Term...Norcross Long Term...Norcross Aviation...Brennan/Norcross Marine...Brennan/Norcross