341
FXUS61 KGYX 051848
AFDGYX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
248 PM EDT WED AUG 5 2026
WHAT HAS CHANGED
A HEAT ADVISORY HAS BEEN ISSUED FOR PORTIONS OF SOUTHEAST NEW
HAMPSHIRE ON THURSDAY.
KEY MESSAGES
1. HEAT AND HUMIDITY BUILD THROUGH LATE WEEK AND PERSIST THROUGH THE
WEEKEND AS A SUBTROPICAL RIDGE OF HIGH PRESSURE DRIVES THE WEATHER
PATTERN FOR NEW ENGLAND.
2. THERE WILL BE DAILY CHANCES FOR STORMS THURSDAY THROUGH
SATURDAY. COVERAGE WILL BE LIMITED WHILE THERE IS POTENTIAL FOR
A FEW STRONG STORMS AND LOCALIZED TORRENTIAL RAINFALL.
DISCUSSION
KEY MESSAGE 1 DESCRIPTION...
THE BERMUDA HIGH BUILDS INTO THE EASTERN SEABOARD THROUGH THE
WEEKEND, BRINGING BUILDING HEAT AND HUMIDITY POSSIBLY EXTENDING INTO
EARLY NEXT WEEK. THIS BRINGS AN EXTENDED PERIOD OF SEASONABLY WARM
TEMPERATURES, COMBINED WITH ANOMALOUSLY HIGH DEW POINTS.
TEMPERATURES THEMSELVES WON'T BE ANYTHING REMARKABLE, WITH
WIDESPREAD HIGHS IN THE UPPER 80S TO LOW 90S ACROSS MUCH OF THE
AREA. ADDITIONALLY, AN AFTERNOON SEA BREEZE IS LIKELY ALONG THE
COASTLINE BOTH THURSDAY AND FRIDAY, BUT THEN LOOKS CONFINED TO THE
MIDCOAST FOR THE WEEKEND.
THE DEW POINTS THEMSELVES WILL BE THE BIGGER STORY, WITH DEW POINTS
PUSHING INTO THE LOW 70S STARTING ON THURSDAY ACROSS SOUTHERN NEW
HAMPSHIRE. THESE DEW POINTS CONTINUE TO EXPAND, AND PUSH INTO THE
LOW TO MID 70S FOR MUCH OF THE AREA FROM FRIDAY THROUGH AT LEAST
SUNDAY.
INCREASINGLY, IT LOOKS LIKE A STRONGER FRONT THAT BRINGS A RETURN TO
COOLER CONDITIONS TAKES LONGER TO ARRIVE, WITH NEXT TUESDAY TO
WEDNESDAY LOOKING LIKE THE MORE LIKELY TIMEFRAME FOR A MORE
SUBSTANTIAL COOL DOWN. BEFORE THIS, A COUPLE OF FRONTS MAKE SOME
PROGRESS INTO NEW ENGLAND, BUT GRADUALLY WASH OUT WITHOUT BRINGING A
NOTICEABLE COOL DOWN. ONE SUCH FRONT IS LIKELY ON SATURDAY, AND
THE CLOUDS, SHOWERS AND STORMS ASSOCIATED WITH IT MAY SERVE AS
A SPOILER FOR THE HIGHER TEMPERATURES EXPECTED ON THE OTHER DAYS
AROUND IT.
WITH THE HEAT AND HUMIDITY BUILDING, A HEAT ADVISORY HAS BEEN
ISSUED FOR PARTS OF SOUTHERN NEW HAMPSHIRE ON THURSDAY AS HEAT
INDICES PUSH INTO THE MID TO UPPER 90S. IT LIKELY TAKES UNTIL
FRIDAY TO SEE MORE WIDESPREAD HEAT INDICES IN THE MID 90S PUSH
INTO THE REST OF THE INTERIOR FORECAST AREA JUST BACK FROM THE
COASTLINE.
KEY MESSAGE 2 DESCRIPTION...
NEW ENGLAND WILL BE POSITIONED ON THE NORTHWEST FLANK OF A SUB
TROPICAL RIDGE THURSDAY THROUGH FRIDAY WITH A LONG WAVE TROUGH
TO THE WEST OVER THE CENTRAL US. SHORT WAVES MOVING THROUGH THE
TROUGH WILL HELP SUPPRESS THE RIDGE BY SATURDAY WITH SATURDAY
HAVING THE HIGHEST CHANCES FOR SHOWERS AND STORMS THROUGH THE
PERIOD.
DEEP SOUTHWEST FLOW WILL ADVECT ANOMALOUS MOISTURE INTO THE
REGION THURSDAY WITH THIS MOISTURE PERSISTING INTO SATURDAY. DEW
POINTS WILL CLIMB INTO THE UPPER 60S ACROSS MUCH OF THE AREA BY
THURSDAY AFTERNOON WITH SOUTHERN NH AND SW MAINE SEEING DEW
POINTS INTO THE LOW 70S. PWATS WILL ALSO CLIMB ABOVE 1.75 INCHES
ACROSS MUCH OF THE AREA WITH POCKETS OF PWATS GREATER THAN 2
INCHES. SURFACE HEATING COMBINED WITH AREAS OF DEW POINTS IN THE
70S WILL YIELD UPWARDS OF 2000 J/KG OF SB CAPE AMID 25-30 KTS OF
DEEP LAYER SHEAR THURSDAY AFTERNOON. THE PROXIMITY TO THE RIDGE
AND LACK OF SURFACE FORCING WILL LIMIT CHANCES FOR AN ISOLATED
STORM ACROSS NEW HAMPSHIRE THURSDAY AFTERNOON. GIVEN THE CAPE
AND SHEAR A STRONG STORM CANNOT BE RULED OUT AND HIGH PWATS
COMBINED WITH DEEP WARM CLOUD DEPTHS WOULD ALLOW FOR TORRENTIAL
RAINFALL. FRIDAY WILL BE SIMILAR WITH THE RIDGE CLOSE BY AND
LACK OF SURFACE FORCING WHILE EXPANDING HIGH DEW POINTS WILL
ALLOW FOR SUFFICIENT INSTABILITY FOR STORMS ACROSS MUCH OF THE
AREA. SHEAR WILL BE SOMEWHAT WEAKER AROUND 25 KTS OR LESS AND
CAMS SHOW LITTLE IN THE WAY OF STORM COVERAGE. GIVEN SUFFICIENT
SB CAPE WITH NO CIN HAVE LARGELY STUCK WITH NBM POPS FRIDAY
AFTERNOON WHICH ARE AROUND 20-30 PERCENT. HIGH PWATS AND DEEP
WARM CLOUD DEPTHS WILL AGAIN ALLOW FOR ANY THUNDERSTORM THAT
DOES DEVELOP BE PROLIFIC RAIN PRODUCERS.
THE 12Z MODEL SUITE IS IN GENERAL AGREEMENT THAT SHORT WAVES
WILL START TO SUPPRESS THE RIDGE FRIDAY NIGHT INTO SATURDAY.
THESE WAVES WILL CONTINUE CHANCES FOR SHOWERS AND STORMS FRIDAY
NIGHT INTO SATURDAY MORNING. FORCING FOR ASCENT REMAINS
FAVORABLE THROUGH SATURDAY EVENING WHILE CLOUD COVER BRINGS INTO
QUESTION HOW MUCH THE ATMOSPHERE CAN DESTABILIZE FOR STORMS.
MODELS GENERALLY SUGGEST THERE WILL BE SUFFICIENT CAPE AND SHEAR
FOR STORMS WITH THE CONTINUED THEME OF HIGH PWATS AND DEEP WARM
CLOUD DEPTHS ALLOWING FOR STORMS TO PRODUCE TORRENTIAL
RAINFALL. SHEAR WILL ALSO BE A BIT STRONGER SO INSTABILITY
TRENDS WILL NEED TO BE WATCHED FOR POTENTIAL STRONG TO SEVERE
STORMS. DAILY CHANCES FOR SHOWERS AND STORMS DIMINISH SUNDAY
INTO MONDAY AS FLOW ALOFT TURNS MORE ZONAL.
AVIATION /18Z WEDNESDAY THROUGH MONDAY/
THROUGH THURSDAY NIGHT: MAINLY VFR TONIGHT WITH VALLEY FOG
LIKELY BRINGING RESTRICTIONS AT LEB AND HIE AND POTENTIAL FOR
RESTRICTIONS AT CON. LIGHT AND VARIABLE FLOW TONIGHT WILL BECOME
S AT 5-15 KTS ON THURSDAY. VFR LIKELY PREVAILS THROUGH THURSDAY
WHILE ISOLATED TSRA CANNOT BE RULED OUT ACROSS NH. INCREASING
MOISTURE WILL BRING POTENTIAL FOR PATCHY FOG ACROSS MUCH OF THE
AREA THURSDAY NIGHT.
OUTLOOK...
FRIDAY: MAINLY VFR, ALTHOUGH AN ISOLATED AFTERNOON TSRA CANNOT
BE RULED OUT. PATCHY FOG IS POSSIBLE FRIDAY NIGHT ALONG WITH LOW
CIGS AND SHRA.
SATURDAY: SCATTERED SHRA/TSRA WILL BRING POTENTIAL FOR
LOCALIZED RESTRICTIONS. CIGS MAY ALSO BE AROUND MVFR THRESHOLDS.
SUNDAY-MONDAY: MAINLY VFR OUTSIDE OF ISOLATED SHRA/TSRA.
MARINE
HIGH PRESSURE DOMINATES OVER THE WATERS THURSDAY AND SLOWLY
SHIFTS SOUTHEAST INTO SATURDAY. INCREASING MOISTURE WILL BRING
POTENTIAL FOR FOG OVER THE WATERS TONIGHT INTO SATURDAY. A FRONT
APPROACHES THE WATERS LATE FRIDAY INTO SATURDAY BRINGING CHANCES
FOR SHOWERS AND STORMS. SOUTH TO SW FLOW GENERALLY PREVAILS
THROUGH THE PERIOD WITH WINDS AND SEAS REMAINING BELOW SCA
THRESHOLDS.
GYX WATCHES/WARNINGS/ADVISORIES
ME...NONE.
NH...HEAT ADVISORY FROM 11 AM TO 8 PM EDT THURSDAY FOR NHZ012-013.
MARINE...NONE.
DISCUSSION...CLAIR/SCHROETER
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