902
FXUS61 KGYX 092321
AFDGYX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
721 PM EDT TUE JUN 9 2026
WHAT HAS CHANGED
715 PM UPDATE...LITTLE CHANGE TO THE GOING FORECAST FOR THIS
EVENING AND OVERNIGHT HOURS OTHER THAN SOME MINOR ADJUSMENTS IN
TEMPERATURES.
PREVIOUSLY...
NO SIGNIFICANT UPDATES NEEDED WITH THIS FORECAST PACKAGE AS
TEMPERATURE AND DEWPOINT TRENDS FOR THIS WEEK REMAIN STEADY.
KEY MESSAGES
1. INCREASING HUMIDITY IS GOING TO POSE AT LEAST A MODERATE
HEAT RISK IN MOST LOCATIONS THROUGH FRIDAY.
2. AFTERNOON SHOWERS AND THUNDERSTORMS MAY POSE AN
EXCESSIVE RAINFALL RISK DUE TO THE ELEVATED MOISTURE AND WEAK UPPER
LEVEL FLOW.
3. OTHER THAN A MOSTLY DRY SUNDAY, DAILY CHANCES OF SHOWERS
RETURN INTO EARLY NEXT WEEK. TEMPERATURES TREND CLOSER TO
NORMAL, PERHAPS A FEW DEGREES ABOVE.
DISCUSSION
KEY MESSAGE 1 DESCRIPTION...
NOT MUCH HAS CHANGED IN REGARDS TO THE HEAT RISK THIS WEEK AS
MODEL TRENDS HAVE HELD STEADY IN REGARDS TO 850 MB TEMPERATURES
RISING TO +15 TO 17C WEDNESDAY AND THEN REMAINING THERE THROUGH
FRIDAY. THIS SHOULD BE GOOD FOR MOST AREAS TO SEE TEMPERATURES
RISING INTO THE UPPER 80S TO 90F EACH DAY. THE EXCEPTIONS ARE
GOING TO BE LOCATIONS IN THE HIGHER TERRAIN AND AT THE COAST
WHERE IT LIKELY ENDS UP A BIT COOLER. THE DEWPOINTS ARE GOING TO
BE MORE DYNAMIC, AND THAT IS WHERE THE DIFFERENCE WILL BE FELT.
MONDAY AND TODAY HAVE FELT QUITE PLEASANT THANKS TO DEWPOINTS
GENERALLY IN THE UPPER 40S AND 50S, BUT BY WEDNESDAY 60F DEGREE
DEWPOINTS BEGIN ENTERING THE PICTURE. WEDNESDAY SHOULDN'T FEEL
OVERLY OPPRESSIVE, BUT THERE IS GOING TO BE A NOTICEABLE
MUGGINESS TAKING HOLD. THURSDAY LOOKS LIKE THE PEAK OF THE
HUMIDITY AS DEWPOINTS CLIMB INTO THE MID TO UPPER 60S ACROSS
MUCH OF THE AREA. THIS MAKES THOSE UPPER 80S AND 90 DEGREE
TEMPERATURES FEEL MORE LIKE THE LOW TO MID 90S. AS HAS BEEN
PREVIOUSLY MENTIONED, THE WARMEST TEMPERATURES LOOK CONFINED TO
THE LOWER NEW HAMPSHIRE RIVER VALLEYS MAKING ANY MAJOR HEAT RISK
THREAT (APPARENT TEMPERATURES >=95F) QUITE ISOLATED.
UNCERTAINTY ALSO REMAINS IN JUST HOW WARM WE ARE ABLE TO GET ON
THURSDAY WITH CURRENT 12Z NBM 25-75TH PERCENTILE SPREAD A GOOD 5
TO 7 DEGREES ACROSS NEW HAMPSHIRE AND 5 TO 9 DEGREES ACROSS
WESTERN MAINE. THE FACTORS BEING THE POSSIBILITY OF CONVECTION
LEADING TO MORE CLOUD COVER FOR THE INTERIOR AND THEN STRENGTH
OF THE SEABREEZE FOR THE COAST. THIS IS A SIMILAR STORY FOR
FRIDAY WHERE SPREAD IS CURRENTLY 10-15 DEGREES ACROSS MOST OF
THE AREA. ALL THIS BEING SAID I DON'T HAVE THE CONFIDENCE TO
DEFINITIVELY SAY IF ANY HEAT ADVISORIES WILL BE NEEDED OR NOT ON
THESE DAYS AT THIS POINT, BUT THE BEST CHANCE CURRENTLY LOOKS
LIKE IT WOULD BE IN SOUTHERN NEW HAMPSHIRE.
KEY MESSAGE 2 DESCRIPTION...
INCREASING HEAT AND HUMIDITY IS GOING TO LEAD TO DAILY CHANCES
FOR AFTERNOON SHOWERS AND THUNDERSTORMS THROUGH AT LEAST FRIDAY.
THE RISK FOR STRONG TO SEVERE STORMS IS DIMINISHING AS THE BEST
UPPER LEVEL FORCING LOOKS TO REMAIN WELL TO OUR WEST. HOWEVER,
THESE SHOWERS AND THUNDERSTORMS ARE STILL GOING TO BE FORMING IN
A VERY MOIST ENVIRONMENT WITH WEAK FLOW ALOFT SO FOCUS MAY HAVE
TO SHIFT TO EXCESSIVE RAINFALL POTENTIAL. IN FACT, LATEST
ENSEMBLE MEANS SUGGEST PWATS RISING INTO THE 1.5 TO NEAR 2 INCH
RANGE DURING THE DAY WEDNESDAY WHICH ON ITS OWN SUGGESTS
DOWNPOURS ARE GOING TO BE LIKELY WITH ANYTHING THAT DEVELOPS.
WHEN COMBINED WITH THE FACT THAT FORECAST SOUNDINGS SHOW UPPER
LEVEL FLOW ONLY AROUND 10KTS, EXCESSIVE RAINFALL DUE TO SLOW
MOVING AND/OR TRAINING STORMS BECOMES SOMETHING THAT NEEDS TO BE
WATCHED. WPC IS CURRENTLY HIGHLIGHTING THE WHITE MOUNTAINS IN A
MARGINAL RISK LARGELY DUE TO THE TERRAIN ENHANCEMENT AND
RESULTING RUNOFF. LOCALLY 1 AND 3 HOUR FLASH FLOOD GUIDANCE IS
LOWEST HERE AS WELL, SUGGESTING THAT 1-2 INCHES IN THAT AMOUNT
OF TIME COULD CAUSE ISSUES. ELSEWHERE IN THE CWA 1 AND 3 HOUR
FLASH FLOOD GUIDANCE IS ON THE ORDER OF 2-3 INCHES, SO WHILE IT
WILL TAKE MORE, IT IS STILL A POSSIBILITY WITH PWATS BEING AS
HIGH AS THEY ARE GOING TO BE. PWATS SLOWLY DECREASE THURSDAY AND
FRIDAY, BUT STILL LOOK TO BE ON THE ORDER OF 1.25-1.5 INCHES
WITH FLOW STILL LIGHT ON THURSDAY, SO A CLOSE EYE IS GOING TO
HAVE TO BE KEPT ON THIS. FLOW INCREASES TO 20-30KTS ON FRIDAY
WHICH IS BETTER, BUT DEPENDING ON HOW THE PREVIOUS DAYS EVOLVE A
RISK COULD STILL EXIST.
KEY MESSAGE 3 DESCRIPTION...
A COLD FRONT WILL BE PASSING THROUGH THE REGION SATURDAY
MORNING WITH SHOWERS EXPECTED TO ACCOMPANY IT. EVEN THOUGH
SATURDAY IS BETTER REPRESENTED IN GUIDANCE, THERE IS SOME
UNCERTAINTY FOR EXPECTED HIGH TEMPERATURES. WITH SHOWERS AND
CLOUDS SPREAD ALONG THE PASSING FRONT, HOW QUICKLY THESE CLEAR
WITH SUNNY BREAKS WILL PLAY A ROLE IN TEMPERATURE RECOVERY. THIS
DIFFERENCE IS MAGNIFIED IN IQR SPREAD FROM POINTS SOUTH
(MORNING RAIN/CLOUD RECOVERY) VS. NORTH (EARLY/MID AFTERNOON
RAIN/CLOUD RECOVERY). FOR EXAMPLE, A MAX TEMPERATURES IQR IN
CONCORD, NH SEES A RANGE OF ABOUT 7 DEGREES VS. AUGUSTA, ME WITH
A RANGE OF AROUND 16 DEGREES.
THE COLD FRONT WILL KNOCK HEAT AND HUMIDITY DOWN INTO EARLY
NEXT WEEK, BUT STILL SEE GOOD REASON TO HAVE FORECAST HIGHS A
COUPLE DEGREES ABOVE NORMAL. THIS MEANS HIGHS IN THE MID TO
UPPER 70S, TO AROUND 80 IN SOUTHERN NH.
FOR PRECIPITATION, NBM DISPLAYS NEARLY A DAILY CHANCE OF
SHOWERS THROUGH MID-WEEK. THIS COULD BE MAGNIFIED BY A WIDE
RANGE OF SOLUTIONS AMONG THE ENSEMBLE, BUT FOR NOW THE
CONFIDENCE IN CALLING A RAIN FREE DAY FOR THE ENTIRE CWA IS LOW.
ONCE GUIDANCE COMES INTO BETTER ALIGNMENT, A DRY DAY COULD BE
IN THE CARDS FOR EITHER SUNDAY OR MONDAY AS HIGH PRESSURE TRIES
TO MAKE ITS WAY THROUGH THE NORTHEAST. ON THE FLIP SIDE, THERE
IS ALSO NOT A LOT OF CONFIDENCE IN A SINGLE DAY BEING A COMPLETE
WASHOUT.
AVIATION /00Z WEDNESDAY THROUGH SUNDAY/
THROUGH 18Z WEDNESDAY...VFR GENERALLY PREVAILS THROUGH
WEDNESDAY MORNING. HIE AND LEB MAY SEE SOME VALLEY FOG TONIGHT
BUT CONFIDENCE IS LOW SO KEPT ANY RESTRICTIONS OUT OF THE TAFS
WITH THIS PACKAGE.
OUTLOOK...
WEDNESDAY AFTERNOON/NIGHT: SCATTERED SHOWERS AND THUNDERSTORMS
BEGIN TO ENTER THE AREA WEDNESDAY AFTERNOON WHICH MAY BRING
ABOUT TEMPO MVFR CONDITIONS. TEMPO IFR IS ALSO POSSIBLE IF A
HEAVIER SHOWER MOVES OVER A TERMINAL. IN THE WAKE OF SHOWERS AND
STORMS, A MORE WIDESPREAD FOG IS POSSIBLE WEDNESDAY NIGHT WITH
IFR CONDITIONS POSSIBLE AT ALL TERMINALS.
THURSDAY-FRIDAY: GENERALLY VFR WITH TEMPO MVFR POSSIBLE IN
SCATTERED SHOWERS AND THUNDERSTORMS. FOG IS POSSIBLE AGAIN
THURSDAY NIGHT.
SATURDAY: SHRA MOVES ALONG A COLD FRONT PUSHING EAST THROUGH THE
DAY. THIS COULD BRING MVFR CIGS, IMPROVING TO VFR SOUTH TO
NORTH.
SATURDAY NIGHT: VFR LIKELY, BUT VALLEY FOG POSSIBLE LATE.
SUNDAY: UNCERTAINTY IN COVERAGE OF SHOWERS AND POSSIBLE
THUNDERSTORMS, OTHERWISE VFR TOWARDS THE COAST.
MARINE
GENERALLY QUIET WEATHER IS EXPECTED ON THE WATERS THROUGH
FRIDAY WITH AFTERNOON SEABREEZES AS HIGH PRESSURE REMAINS IN THE
VICINITY OF THE GULF OF MAINE. INCREASING MOISTURE WILL LIKELY
LEAD TO FOG DEVELOPMENT FROM MIDWEEK THROUGH FRIDAY.
A COLD FRONT WILL CROSS THE WATERS SATURDAY AFTERNOON, BUT
CURRENT FORECASTS CALL FOR WINDS AND SEAS REMAINING BELOW SCA
CRITERIA INTO EARLY NEXT WEEK.
GYX WATCHES/WARNINGS/ADVISORIES
ME...NONE.
NH...NONE.
MARINE...NONE.
DISCUSSION...BARON/CORNWELL/EKSTER
AVIATION...
MARINE...
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