585
FXUS61 KGYX 151808
AFDGYX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
208 PM EDT MON JUN 15 2026
WHAT HAS CHANGED
A COASTAL FLOOD STATEMENT HAS BEEN ISSUED FOR PORTLAND AND
POINTS SOUTH FOR TONIGHT'S HIGH TIDE CYCLE.
KEY MESSAGES
1. SEASONABLE TEMPERATURES WILL PERSIST INTO TUESDAY WITH
COMFORTABLE OVERNIGHT LOWS. HIGH ASTRONOMICAL TIDES WILL
CONTINUE INTO THE MIDDLE OF THE WEEK AND MINOR FLOODING REMAINS
POSSIBLE AROUND THE TIMES OF HIGH TIDE.
2. AN UNSETTLED SECOND HALF OF THE WEEK IS LIKELY WITH MULTIPLE
ROUNDS OF SHOWERS AND THUNDERSTORMS IN THE FORECAST.
DISCUSSION
KEY MESSAGE 1 DESCRIPTION...
DIURNALLY DRIVEN CUMULUS WILL DISSIPATE THIS EVENING WITH THE
LOSS OF DAYTIME HEATING. SKIES OVERNIGHT WILL BE CLEAR TO PARTLY
CLOUDY, WHICH COMBINED WITH WEAKENING WINDS WILL ALLOW FOR SOME
RADIATIONAL COOLING. OVERNIGHT LOWS WILL RANGE FROM THE 40S
ACROSS THE NORTH AND INTERIOR VALLEYS WITH 50S ELSEWHERE. SOME
VALLEY FOG IS POSSIBLE AFTER MIDNIGHT.
TUESDAY WILL FEATURE DRY CONDITIONS WITH MAINLY SUNNY SKIES AND
HIGH TEMPERATURES INTO THE 70S TO NEAR 80 DEGREES FROM NORTH TO
SOUTH. TUESDAY NIGHT WILL BE ANOTHER COMFORTABLE NIGHT WITH LOW
TEMPERATURES FALLING INTO THE 40S AND 50S.
HIGH ASTRONOMICAL TIDES WILL PERSIST THROUGH THE MIDDLE OF THIS
WEEK WITH MINOR COASTAL FLOODING POSSIBLE AROUND THE TIMES OF
HIGH TIDE EACH NIGHT, ESPECIALLY FROM PORTLAND AND POINTS SOUTH.
A COASTAL FLOOD STATEMENT HAS BEEN ISSUED FOR PORTLAND AND
POINTS SOUTH FOR TONIGHT.
KEY MESSAGE 2 DESCRIPTION...
SURFACE HIGH PRESSURE WILL MOVE EAST AND OUT TO SEA ON WEDNESDAY AS
A SHORTWAVE TROUGH STARTS TO APPROACH FROM THE WEST. WARM AIR
ADVECTION COULD LEAD TO SOME SHOWERS WITH A SLIGHT CHANCE OF
THUNDERSTORMS, ESPECIALLY OVER THE MOUNTAINS. THIS ACTIVITY SHOULD
BE VERY HIT OR MISS AND WILL LIKELY DIMINISH IN THE EVENING WITH THE
LOSS OF DAYTIME HEATING.
A STRONGER UPPER LOW THEN MOVES FROM ONTARIO INTO SOUTHERN QUEBEC ON
THURSDAY, WHICH SHOULD LEAD TO WIDESPREAD HIGH PRECIPITATION CHANCES
(GREATER THAN 70 PERCENT) ACROSS PRETTY MUCH ALL OF NEW HAMPSHIRE
AND WESTERN MAINE. ISOLATED TO SCATTERED THUNDERSTORMS WILL ALSO BE
LIKELY AS THIS SYSTEM MOVES INTO THE REGION AND A SURFACE LOW
DEEPENS OVER QUEBEC WITH A COLD FRONT TRAILING TO THE
SOUTH/SOUTHWEST. WHILE THE SYSTEM HAS TRENDED A BIT FASTER THAN IN
PREVIOUS DAYS, STRONG FORCING, VERY STRONG SHEAR, AND WEAK TO
MODERATE INSTABILITY COULD LEAD TO SOME EARLY TO LATE AFTERNOON
STRONG TO SEVERE STORMS. THE BEST ENVIRONMENT WILL LIKELY BE OVER
THE SOUTHERN HALF OF NEW HAMPSHIRE, WHERE NAM SOUNDINGS SUGGEST WE
COULD SEE DEWPOINTS INTO THE MID TO UPPER 60S, MLCAPE VALUES AROUND
500 J/KG, AND MUCAPE AROUND 1000 J/KG. ADDITIONALLY, SHEAR PROFILES
LOOK MORE LIKE SOMETHING WE WOULD USUALLY SEE FROM A COOL SEASON
SETUP WITH 0-1 KM VALUES UP TO 40 KNOTS AND 0-6 KM VALUES WELL OVER
60 KNOTS. AT FACE VALUE, THESE SHEAR VALUES WOULD BE VERY CONCERNING
FOR SEVERE WEATHER BUT PLENTY OF FLIES REMAIN IN THE OINTMENT THIS
FAR OUT. FOR ONE, WE WILL LIKELY SEE QUITE A BIT OF EARLY DAY
CONVECTION/RAIN/CLOUD COVER WHICH COULD LIMIT THE ALREADY MARGINAL
INSTABILITY THAT MODELS ARE FORECASTING. THE BEST KINEMATIC
ENVIRONMENT WILL BE IN THE POTENTIAL DRY SLOTTING BEHIND THIS EARLY
DAY CONVECTION WHICH MAY NOT CLEAR OUT IN TIME FOR ENOUGH
DESTABILIZATION. THE ECMWF AND IT'S ENSEMBLE KEEP TEMPERATURES MUCH
COOLER WITH LOWER DEWPOINTS THAN THE NBM WHICH WOULD ALSO REDUCE THE
THREAT SIGNIFICANTLY. SECONDLY, FORECAST MID-LEVEL LAPSE RATES ARE
UNIMPRESSIVE WHICH IS LIKELY A RESULT OF THE EARLY DAY
CONVECTION/CLOUDS. ALL THAT SAID, IT WILL BE INTERESTING TO SEE THE
FORECAST TRENDS AS WE MOVE INTO THE RANGE OF THE CAMS OVER THE NEXT
COUPLE OF DAYS AND GET A BETTER IDEA OF TIMING AND FINER MESOSCALE
FEATURES. A FEW FAST MOVING STRONG TO SEVERE THUNDERSTORMS WILL BE
POSSIBLE DEPENDING ON THE EVOLUTION OF SAID FEATURES. LOCALLY HEAVY
RAINFALL WILL ALSO BE POSSIBLE, BUT MODELED PRECIPITABLE WATER IS
FORECAST TO BE AROUND AVERAGE FOR THIS TIME OF YEAR AND THE SYSTEM
SHOULD QUICKLY MOVE OUT THURSDAY NIGHT.
ENSEMBLES FAVOR TROUGHING STICKING AROUND THROUGH THE WEEKEND SO THE
PATTERN MAY REMAIN UNSETTLED WITH NEAR DAILY CHANCES OF SHOWERS AND
STORMS, ESPECIALLY ACROSS THE HIGHER TERRAIN.
REGARDING TEMPERATURES, WEDNESDAY SHOULD BE A LITTLE BIT WARMER THAN
ON TUESDAY WITH HIGHS MAINLY IN THE LOWER 70S TO LOWER 80S.
TEMPERATURES WILL THEN BE FAIRLY SIMILAR THROUGH THE REST OF THE
WORK WEEK AND THROUGH THE WEEKEND, BUT MAYBE A LITTLE BIT COOLER IN
THE MOUNTAINS AND A TOUCH WARMER ALONG THE COAST AT TIMES.
AVIATION /18Z MONDAY THROUGH SATURDAY/
THROUGH 18Z TUESDAY: VFR CONDITIONS EXPECTED. THE EXCEPTION MAY
BE AT KHIE WHERE VALLEY FG IS POSSIBLE LATE TONIGHT INTO EARLY
TUESDAY MORNING, ALTHOUGH FORECAST CONFIDENCE IS LOW. NW WIND
GUSTS UP TO 25 KTS WILL REMAIN POSSIBLE THROUGH 00Z BEFORE
BECOMING LIGHT AND VARIABLE OVERNIGHT AND THEN NW AT 5-15 KTS ON
TUESDAY. NO LLWS IS ANTICIPATED.
TUESDAY NIGHT: VFR CONDITIONS WITH LIGHT AND VARIABLE WINDS.
OUTLOOK:
WEDNESDAY: VFR CONDITIONS GENERALLY EXPECTED. LOCAL MVFR OR
LOWER POSSIBLE IN THE AFTERNOON OR EARLY EVENING UNDER ISOLATED
SHOWERS AND THUNDERSTORMS.
THURSDAY - THURSDAY NIGHT: AREAS OF MVFR OR LOWER POSSIBLE UNDER
SHOWERS AND THUNDERSTORMS AND LOW CIGS.
FRIDAY: LOW CIGS MAY LINGER INTO FRI BEFORE CLEARING DURING THE
AFTERNOON.
FRIDAY NIGHT - SATURDAY: VFR CONDITIONS GENERALLY EXPECTED.
LOCAL MVFR OR LOWER POSSIBLE UNDER ISOLATED SHOWERS AND
THUNDERSTORMS.
MARINE
WINDS WILL REMAIN OFFSHORE THROUGH TUESDAY NIGHT WITH GUSTS
REMAINING LARGELY BELOW 20 KTS AND SEAS OF 1-3 FT.
WINDS AND SEAS REMAIN BELOW SCA THRESHOLDS UNTIL THE NEXT
SYSTEM ARRIVES THURSDAY. SOUTHEASTERLY WINDS TURNING
SOUTHWESTERLY MAY GUST UP TO 30 KT WITH SEAS BUILDING ABOVE 5 FT
OUTSIDE OF THE BAYS.
GYX WATCHES/WARNINGS/ADVISORIES
ME...NONE.
NH...NONE.
MARINE...NONE.
DISCUSSION...TUBBS/HARGROVE
AVIATION...TUBBS/HARGROVE
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