170
FXUS61 KCAR 180757
AFDCAR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CARIBOU ME
357 AM EDT MON MAY 18 2026
WHAT HAS CHANGED
-CONTINUED TO LOWER DEWPOINTS FOR TODAY
-MADE A GENERAL AREA OF THUNDER ON TUESDAY. CONFIDENCE IN SOME
STORM DEVELOPMENT ON TUESDAY INCREASES.
-ADDED THUNDERSTORM POTENTIAL FOR DOWNEAST AREAS WEDNESDAY
-ADDED KEY MESSAGE FOR FROST/FREEZE POTENTIAL EARLY FRIDAY
MORNING AND BELOW AVERAGE TEMPERATURES
-REMOVED KEY MESSAGE FOR RAIN SUNDAY AS CHANCES HAVE DECREASED
AND THE OVERALL IMPACT IS LOW IF IT OCCURS
KEY MESSAGES
1) DRY AND BREEZY CONDITIONS TODAY, POTENTIALLY LEADING TO SOME
FIRE WEATHER CONCERNS.
2) CHANCE FOR THUNDERSTORMS AND WARM TEMPERATURES TUESDAY AND
WEDNESDAY AFTERNOON. A FEW STRONGER STORMS ARE POSSIBLE.
3) BELOW AVERAGE TEMPERATURES ARE EXPECTED THURSDAY AND THURSDAY
NIGHT. NEAR FREEZING TEMPERATURES ARE POSSIBLE EARLY FRIDAY
MORNING ACROSS THE NORTH, WHICH MAY REQUIRE ACTIONS TO PROTECT
VULNERABLE PLANTS.
DISCUSSION
KEY MESSAGE 1...DRY AND BREEZY CONDITIONS TODAY, POTENTIALLY
LEADING TO SOME FIRE CONCERNS.
KEY MESSAGE 1 DESCRIPTION...
PERIOD OF HIGH PRESSURE TODAY, AS A WARM FRONT SLOWLY BEGINS TO
APPROACH FROM THE SOUTHWEST. FRONT TO THE SOUTHWEST BRINGS IN A
FEW CLOUDS, HELPING TO KEEP DAYTIME HIGH TEMPERATURES AROUND
THE MID-60S IN NORTHERN AND EASTERN MAINE. VERY DRY MID-LEVEL
MOISTURE BASED ON SOUNDING ANALYSIS, WITH DAYTIME MINIMUM RHS
EXPECTED TO BE UPPER 20S/LOW 30S IN THE NORTHWEST, AND LOW 20S
IN NORTHERN AND EASTERN MAINE. WINDS SHIFT TO THE SOUTHWEST,
WITH SOME BREEZY CONDITIONS DURING THE EARLY EVENING,
PREDOMINANTLY DOWNEAST.
KEY MESSAGE 2...CHANCE FOR THUNDERSTORMS AND WARM TEMPERATURES
TUESDAY AND WEDNESDAY AFTERNOON. A FEW STRONGER STORMS ARE
POSSIBLE.
KEY MESSAGE 2 DESCRIPTION...
RIDGING OVER THE CENTRAL ATLANTIC MOVES EAST MONDAY NIGHT, AS A
LOW PRESSURE SYSTEM AND ASSOCIATED WARM FRONT MOVES INTO THE
REGION BY TUESDAY MORNING. A MID-LEVEL SHORTWAVE MOVES THROUGH
DURING THE AFTERNOON INTO THE EVENING. THE REGION WARMS UP AS A
WARM FRONT PASSES, RAISING DAYTIME HIGHS TO ROUGHLY LOW-70S UP
NORTH, LOW-80S IN THE CENTRAL HIGHLANDS, AND MID-80S IN THE
BANGOR AND DOWNEAST REGION. CURRENT UNCERTAINTY RESIDES IN THE
TIMING OF THE FRONTAL SYSTEM, AS THIS WILL HEAVILY IMPACT
DAYTIME TEMPERATURES AND PRECIPITATION TIMING.
INSTABILITY RISES DURING THE AFTERNOON, BRINGING WITH IT THE
CHANCE FOR SOME THUNDERSTORMS ACROSS THE CENTRAL HIGHLANDS,
BANGOR TO DOWNEAST REGION. ON TUESDAY, POTENTIAL FOR ROUGHLY
1500 J/KG OF CAPE, DECENT SHEAR PARAMETERS, AND PWATS ROUGHLY
AROUND 1.25 - 1.75 INCHES. THE MAIN THREAT WITH THESE STORMS
SEEMS TO BE SEVERE WIND GUSTS, AS LOW-LEVEL LAPSE RATES ARE
CLOSE TO 7 - 7.5C/KM, AND DCAPE IS AROUND 600-800 J/KG. THERE
IS ALSO A CHANCE FOR SOME HAIL TO FALL FROM SOME OF THESE
STORMS. MAKE SURE TO HAVE ACCESS TO WAYS FOR RECEIVING WARNING
ALERTS IF A STORM DEVELOPS IN YOUR AREA. THUNDERSTORM POTENTIAL
WILL BEGIN TO DISSIPATE BY NIGHTTIME.
BY WEDNESDAY A STRONG COLD FRONT WILL APPROACH THE AREA,
ACCOMPANIED BY MUCH DRIER AIR AT ALL LEVELS BEHIND IT. MODELS
DIFFER SIGNIFICANTLY WITH THE TIMING OF THE FRONT, WITH THE NAM
AND GFS ON THE FASTER AND THE CMC/ICON/ECMWF ON THE SLOWER END.
A FASTER SOLUTION WOULD RESULT IN LITTLE TO NO CONVECTION AS
DEEPER MOISTURE IS FORCED OVER THE OCEAN WHERE CONDITIONS ARE
EXTREMELY STABLE. SLOWER SOLUTIONS WOULD RESULT IN A NARROW BAND
OF 500-1000 J/KG OF MLCAPE ACROSS BANGOR INTO DOWNEAST MAINE,
WHICH COMBINED WITH STRONGER WINDS ALOFT PROVIDING 30-40 KTS OF
0-3KM EFFECTIVE WIND SHEAR, COULD LEAD TO AN ISOLATED
THUNDERSTORM CAPABLE OF STRONG TO DAMAGING WINDS FOR COASTAL AND
DOWNEAST AREAS. A MAJORITY OF THE TIME, SLOWER SOLUTIONS FOR
FRONTAL PASSAGES VERIFY THIS TIME OF YEAR, SO ADJUSTMENTS WERE
MADE TO EXPAND POPS AND INTRODUCE THUNDER CHANCES MAINLY
DOWNEAST AND OVER THE NEAR COASTAL WATERS. THE SPEED OF THE
FRONT WILL ALSO IMPACT TEMPERATURES, WITH SLOWER SOLUTIONS
POTENTIALLY ALLOWING 80S TO REACH FARTHER TO THE NORTH. MAX
TEMPERATURES MAINLY IN THE 70S ARE FORECAST FOR NORTHWESTERN
WITH 80S MOST LIKELY NEAR AND SOUTHEAST OF INTERSTATE 95. DEW
POINTS IN THE 60S EARLY WILL MAKE IT FEEL A SOMEWHAT HUMID, BUT
DRIER AIR AND MUCH LOWER DEW POINTS WILL QUICKLY MOVE IN BEHIND
THE FRONT IN THE AFTERNOON FROM NORTHWEST TO SOUTHEAST.
KEY MESSAGE 3...BELOW AVERAGE TEMPERATURES ARE EXPECTED THURSDAY
AND THURSDAY NIGHT. NEAR FREEZING TEMPERATURES ARE POSSIBLE
EARLY FRIDAY MORNING ACROSS THE NORTH, WHICH MAY REQUIRE ACTIONS
TO PROTECT VULNERABLE PLANTS.
KEY MESSAGE 3 DESCRIPTION...
THE FROST/FREEZE PROGRAM, MARKING THE APPROXIMATE BEGINNING OF
THE GROWING SEASON, WILL EXPAND NORTH ON THURSDAY TO INCLUDE
MOST OF THE REMAINDER OF NORTHERN AND EASTERN MAINE ASIDE FROM
THE FAR NORTHWESTERN FORECAST ZONES. STRONG COLD AIR ADVECTION
IS EXPECTED ON THURSDAY WITH 1000-500MB THICKNESSES DECREASING
BELOW 540DAM ACROSS MUCH OF NORTHERN MAINE BY THURSDAY EVENING.
WHILE WINDS WILL BE LIGHTER THURSDAY NIGHT, THE CENTER OF THE
RIDGE OF HIGH PRESSURE IS EXPECTED TO BE WELL TO THE SOUTHWEST
ACROSS NORTHERN NY, VT, AND WESTERN MA, HELPING TO MAINTAIN A
MODEST NW WIND OUTSIDE OF SHELTERED VALLEYS. A STRONG JET STREAK
OVERHEAD WILL ALSO MAINTAIN THE RISK FOR PASSING CLOUDS. THESE
FACTORS MAKE THE ACTUAL DEGREE OF DECOUPLING UNCERTAIN.
TEMPERATURES AT OR BELOW FREEZING ARE MOST LIKELY OVER THE NORTH
WOODS WHERE THE GROWING SEASON DOES NOT START UNTIL JUNE 1. LOWS
RANGING FROM THE MID 30S TO LOWER 40S ARE FAVORED ELSEWHERE
EARLY FRIDAY MORNING.
AVIATION /07Z MONDAY THROUGH FRIDAY/
TODAY...VFR. WINDS SHIFT FROM NW TO W BY LATER IN THE MORNING.
GUSTS UP TO 20 KTS POSSIBLE AROUND KBGR.
TONIGHT...VFR/MVFR, WITH SOME RAIN SHOWERS AT NORTHERN
TERMINALS. S WINDS AT 5 - 10 MPH. LLWS POSSIBLE.
TUESDAY...MVFR, POTENTIALLY LOWER IN TERMINALS WITH SEVERE
THUNDERSTORMS. BEST CHANCE FOR THUNDERSTORMS IS DURING THE
AFTERNOON INTO EVENING. WSW WINDS G15-20KT POSSIBLE TUESDAY
AFTERNOON. LLWS POSSIBLE.
TUESDAY NIGHT: MVFR POSSIBLE AT NORTHERN TERMINALS, IFR
POSSIBLE AT KFVE. VFR ELSEWHERE. SW WINDS 5 TO 10 KTS GUSTING TO
20 KTS.
WEDNESDAY: MVFR EARLY AT NORTHERN TERMINALS, OTHERWISE VFR.
TEMPO MVFR/IFR IS POSSIBLE AT BGR AND DOWNEAST TERMINALS WITH A
CHANCE OF A TSRA. WINDY WITH WSW WINDS TURNING WNW AT 15 TO 20
KTS WITH GUSTS TO 30 TO 35 KTS.
WEDNESDAY NIGHT TO THURSDAY: VFR. NW WINDS 10 TO 15 KTS WITH
GUSTS TO 25 TO 30 KTS.
THURSDAY NIGHT: VFR. NW WINDS 5 TO 10 KTS.
FRIDAY: VFR. NW WINDS 10 TO 15 KTS GUSTING TO 20 TO 30 KTS.
MARINE
WINDS STAY BELOW SCA MONDAY NIGHT, BEFORE CREEPING
NEAR MARGINAL SMALL CRAFT CRITERIA FOR THE OUTER WATERS
TUESDAY. CHANCE FOR RAIN MONDAY NIGHT AND TUESDAY. S WINDS,
BECOMING SW ON TUESDAY.
MARGINAL SMALL CRAFT ADVISORY SEAS AROUND 4 TO 6 FEET ARE
POSSIBLE OVER THE OUTER WATERS OUT TO 25NM TUESDAY NIGHT THROUGH
WEDNESDAY EVENING. WAVE HEIGHTS TO AROUND 5 TO 7 FEET ARE
POSSIBLE ACROSS THE OUTERMOST WATERS FROM 25 TO 60NM. WINDS
BELOW ADVISORY LEVELS ARE EXPECTED THROUGH THE FORECAST PERIOD,
ALTHOUGH SOME 25 KT GUSTS ARE POSSIBLE ACROSS THE OUTERMOST
WATERS FROM 25 TO 60NM OFFSHORE TUESDAY NIGHT INTO WEDNESDAY.
AN ISOLATED THUNDERSTORM IS POSSIBLE WEDNESDAY AFTERNOON,
MAINLY CLOSER TO THE COAST. THESE THUNDERSTORMS MAY PRODUCE
LOCALLY STRONGER WIND GUSTS.
SEA SURFACE TEMPERATURES REMAIN VERY COLD, BUT ARE BEGINNING TO
MODERATE INTO THE MID 40S.
CAR WATCHES/WARNINGS/ADVISORIES
ME...NONE.
MARINE...NONE.
DISCUSSION...ASB/MWS
AVIATION...ASB/MWS
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