068
FXUS61 KGYX 131832
AFDGYX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
232 PM EDT MON JUL 13 2026
WHAT HAS CHANGED
THE HEAT ADVISORY FOR TUESDAY HAS BEEN EXPANDED TO INCLUDE
COASTAL CUMBERLAND COUNTY. CONFIDENCE CONTINUES TO INCREASE WITH
THE THREAT FOR SEVERE WEATHER TUESDAY EVENING INTO TUESDAY
NIGHT.
KEY MESSAGES
1. HOT AND HUMID TUESDAY WITH A HEAT ADVISORY IN EFFECT FOR MUCH OF
NORTHERN NEW ENGLAND.
2. SEVERE WEATHER, POTENTIALLY SIGNIFICANT, IS LIKELY FROM LATE
AFTERNOON INTO THE EARLY OVERNIGHT HOURS ON TUESDAY. THE
HIGHEST THREAT FOR SEVERE WEATHER IS EXPECTED TO BE FROM 6PM
THURSDAY EVENING TO 2 AM TUESDAY NIGHT. DAMAGING WINDS, LARGE
HAIL, TORNADOES, AND FREQUENT LIGHTNING ARE ALL POSSIBLE.
3. HUMIDITY ABATES WEDNESDAY WHILE HOT CONDITIONS CONTINUE WITH
BREEZY WINDS.
4. COLD FRONT CROSSES THURSDAY BRINGING CHANCES FOR SHOWERS AND
STORMS ALONG WITH A SLIGHT COOLING TREND INTO THE WEEKEND.
DISCUSSION
KEY MESSAGE 1 DESCRIPTION...
LATEST RAP ANALYSIS INDICATES A 500MB SHORTWAVE MOVING ACROSS
QUEBEC THIS AFTERNOON WITH SATELLITE AND RADAR MOSAIC AN AREA OF
INCREASED CLOUD COVER AND SHOWERS. THIS WAVE WILL CROSS
NORTHERN NEW ENGLAND LATER TODAY BRINGING A ROUND OF MOSTLY
LIGHT SHOWERS, MAINLY OVER THE NORTHERN HALF OF NH AND INTO
PORTIONS WESTERN ME LATER THIS AFTERNOON AND EVENING. CAN'T
COMPLETELY RULE OUT A RUMBLE OF THUNDER, BUT BASED ON FORECAST
SOUNDINGS THE POTENTIAL LOOKS VERY LOW. THESE SHOWERS SHOULD
PUSH OFF TO THE EAST AND OUT OF THE AREA BY AROUND MIDNIGHT OR
SO WITH DRY AND MILD CONDITIONS OVERNIGHT. HOWEVER, WILL HAVE TO
WATCH FOR SHOWER OR STORMS DROPPING SOUTH OUT OF CANADA LATE
AND INTO THE EARLY PART OF TUESDAY MORNING. THERE IS GOOD
AGREEMENT THAT THESE WILL BE ON A WEAKENING TREND AS THEY
APPROACH THE INTERNATIONAL BORDER, BUT VARIOUS RUNS/SOLUTIONS
INDICATE THE POSSIBILITY OF HOLDING TOGETHER LONG ENOUGH TO
CROSS INTO NORTHERN NH OR NORTHWESTERN ME.
FOR TUESDAY, WARMER AND MORE HUMID AIR CONTINUE TO ADVECT INTO THE
AREA AHEAD OF A COLD, RESULTING IN A HOT AND HUMID DAY. 850MB
TEMPERATURES OF +19C TO +22C SUPPORT HIGH TEMPERATURES IN THE 90S
FOR MOST OF NORTHERN NEW ENGLAND, AND DEWPOINTS ARE EXPECTED TO
INCREASE TO THE MID-UPPER 60S, BRINGING HEAT INDICES IN THE MID 90S
TO LOW 100S, WHICH IS A SOLID HEAT ADVISORY. THE ONLY CHANGE MADE TO
THE EXISTING HEAT ADVISORY WAS EXPANDING IT TO INCLUDE COASTAL
CUMBERLAND COUNTY.
KEY MESSAGE 2 DESCRIPTION...
NOW TO THE INCREASING THREAT FOR SEVERE WEATHER, WHICH AGAIN
COULD BE POTENTIALLY SIGNIFICANT. AN ENHANCED RISK (LEVEL 3/5)
OF SEVERE WEATHER IS IN PLACE FOR NORTHERN NH AND THE WESTERN ME
MOUNTAINS,A SLIGHT RISK (LEVEL 2/5) FOR CENTRAL NH AND THE
MAINE INTERIOR, AND A MARGINAL RISK (LEVEL 1/5) FOR COASTAL ME
AND APPROACHING SOUTHERN NH.
A POTENT 500MB SHORTWAVE WILL CROSS QUEBEC IN THE AFTERNOON AND
EVENING, WITH ITS ASSOCIATED COLD FRONT APPROACHING THE
INTERNATIONAL BORDER FROM THE NORTHWEST EARLY TUESDAY EVENING.
INCREASING FORCED ASCENT, SIGNIFICANT HEIGHT FALLS, AND
STRENGTHENING WIND FIELDS ALOFT WILL SET THE STAGE FOR SEVERE
THUNDERSTORMS TO DEVELOP WITH THE HOT AND HUMID AIR MASS IN PLACE,
FURTHER ENHANCED BY AN ELEVATED MIXED LAYER THAT WILL STEEPEN LAPSE
RATES ALOFT.
TODAY'S 12Z MODEL SUITE, INCLUDING CAMS, CONTINUE TO SHOW DEEP
LAYER SHEAR OF 50-60 KT, MUCAPE IN THE 2000-2500 J/KG RANGE, AND
HIGH VALUES OF DCAPE (800-1000 J/KG) BROUGHT ON BY SOME DRY
AIR/HIGH DEWPOINT DEPRESSIONS IN THE LOW LEVELS. THIS SUPPORTS
DAMAGING WIND GUSTS, AND GIVEN THE PARAMETERS, THERE'S CERTAINLY
POTENTIAL FOR THESE TO BE SIGNIFICANT ON THE ORDER OF 75+ MPH.
IN ADDITION, THE INSTABILITY PROFILES AND STEEP MID-LEVEL LAPSE
RATES ON FORECAST SOUNDINGS DEPICT LARGE HAIL COULD BE TO THE
SIZE OF GOLF BALLS OR EVEN LARGER. THERE IS ALSO ENOUGH
DIRECTIONAL SHEAR TO SUPPORT A TORNADO THREAT WITH MEAN 0-1KM
SRH OF 100-200 M^2/S^2. THESE HAZARDS ARE ALL POSSIBLE WITHIN
DISCRETE OR SEMI-DISCRETE STORM MODE, BUT THE PRIMARY HAZARD
WILL BECOME DAMAGING WINDS WHEN THE DOMINANT MODE BECOMES MORE
LINEAR, ALTHOUGH A TORNADO WITHIN THE LINE(S) WILL REMAIN
POSSIBLE.
FOR TIMING: THERE'S STRONG CONSENSUS AMONG THE CAMS WITH
MULTIPLE CLUSTERS OR SEMI-DISCRETE DEVELOPING ACROSS SOUTHERN
QUEBEC IN THE LATE AFTERNOON TO EARLY EVENING WITH RAPID UPSCALE
GROWTH IN COVERAGE AND INTENSITY AS STORMS APPROACH NORTHERN NH
AND NORTHWESTERN ME IN THE 6PM TO 8PM TIME FRAME. STORMS ARE
EXPECTED TO QUICKLY PROGRESS TO THE SOUTH THE REST OF THE
EVENING INTO THE EARLY OVERNIGHT HOURS. HOWEVER, IT SHOULD BE
NOTED THERE ARE HINTS OF ISOLATED DISCRETE CELLS DEVELOPING IN
THE 4PM TO 6PM TIMEFRAME THAT MAY APPROACH FROM THE NORTH. BASED
ON CAM SOLUTIONS, THE THREAT FOR SEVERE WEATHER SHOULD DIMINISH
AFTER 2 AM, BUT SOME DEVELOPMENT OF SHOWERS AND A FEW STORMS IS
POSSIBLE OVERNIGHT.
THIS IS NOT A YEARLY, TYPICAL THREAT OF SEVERE STORMS, AND IT
BECOMES EVEN MORE DANGEROUS AS THE THREAT CONTINUES AFTER DARK. IT
IS HIGHLY ADVISED TO HAVE MULTIPLE WAYS TO RECEIVE WARNINGS,
ESPECIALLY ONES THAT WILL WAKE YOU UP WITH THE THREAT CONTINUING
INTO THE LATE EVENING AND EARLY OVERNIGHT HOURS. THE HIGHEST RISK
AREAS ALSO INCLUDE MANY POPULAR CAMPING AND RECREATION AREAS,
WHICH MAKE THOSE WHO ARE OUTDOORS EXTREMELY VULNERABLE TO
FALLING TREES.
KEY MESSAGE 3 DESCRIPTION...
THE COLD FRONT RESPONSIBLE FOR SEVERE STORMS WILL BE PUSHING
OFFSHORE WEDNESDAY MORNING. DRIER AIR MOVING INTO THE REGION
ALONG WITH DEEP MIXING WILL ALLOW FOR DEW POINTS TO DROP INTO
THE 50S. TEMPERATURES ALOFT WILL REMAIN WARM AND WITH DEEP
MIXING HIGHS WILL CLIMB INTO THE UPPER 80S TO LOW 90S. WINDS AT
THE TOP OF THE MIXED LAYER WILL BE AROUND 30 KTS WHICH WILL
RESULT IN SURFACE GUSTS 25 TO 30 MPH FROM LATE MORNING THROUGH
THE AFTERNOON.
KEY MESSAGE 4 DESCRIPTION...
A TROUGHING PATTERN WILL LINGER OVER THE NORTHEAST THROUGH THE END
OF THE WEEK. A SHORT WAVE EMBEDDED WITHIN THE TROUGH WILL SEND
ANOTHER COLD FRONT THROUGH THE REGION THURSDAY EVENING. DEW POINTS
IN THE 50S WILL LIMIT INSTABILITY AHEAD OF THE FRONT WHILE MU CAPE
MAY STILL BUILD TO AROUND 1000 J/KG. THE 12Z MODEL SUITE IS IN
DECENT AGREEMENT THAT THE FRONT WILL BRING CHANCES FOR SHOWERS AND
STORMS THURSDAY AFTERNOON AND EVENING, WITH THE BEST CHANCES ALONG
AND NORTH OF THE MOUNTAINS. PRIOR TO THE ARRIVAL OF THE FRONT BREEZY
WEST WINDS WILL CONTINUE HOT AND DRY CONDITIONS SOUTH OF THE
MOUNTAINS WITH HIGHS IN THE UPPER 80S AND LOW 90S. A COOLER AIR MASS
MOVES IN BEHIND THE FRONT THAT WILL HELP KEEP HIGH TEMPERATURES IN
THE 70S AND 80S FRIDAY INTO THE WEEKEND. ADDITIONAL DISTURBANCES
ROTATING THROUGH THE TROUGH WILL BRING CHANCES FOR SHOWERS OVER THE
WEEKEND WHILE CHANCES ARE LOW IN THE 20 TO 40 PERCENT RANGE.
AVIATION /18Z MONDAY THROUGH SATURDAY/
THROUGH 18Z TUESDAY...MAINLY VFR THIS AFTERNOON AND EVENING, BUT A
ROUND OF SHOWERS COULD BRING MVFR VISIBILITIES, MAINLY TO AUG, RKD,
AND HIE. FOR TONIGHT, PATCHY FOG MAY BRING IFR RESTRICTIONS TO AUG
AND RKD BUT OTHERWISE VFR. WILL ALSO HAVE TO SEE ABOUT ANY SHOWERS
OR A STORM MOVING IN FROM THE NORTH, BUT CHANCES APPEAR TOO LOW.
VFR IS LIKE THE REST OF TUESDAY MORNING INTO EARLY AFTERNOON.
OUTLOOK:
TUESDAY AFTERNOON-TUESDAY NIGHT: SHOWERS AND THUNDERSTORMS ARE
LIKELY WITH POTENTIAL FOR IFR RESTRICTIONS. SOME STORMS TO SEVERE
WITH LARGE HAIL, WIND GUSTS OVER 50 KT, AND EVEN A TORNADO. ALL
TERMINALS ARE IN PLAY, BUT HIGHEST CHANCES ARE AT HIE AND AUG WITH
THE LOWER OF THE CHANCES AT MHT AND PSM. LLWS MAY ALSO BE NEEDED FOR
TUESDAY NIGHT.
WEDNESDAY/WEDNESDAY NIGHT: VFR CONDITIONS WITH DAYTIME NW WIND
GUSTS UP TO 25 KTS.
THURSDAY-SATURDAY: MAINLY VFR CONDITIONS WITH WNW FLOW
PREVAILING. SHRA/TSRA THURSDAY AFTERNOON/EVENING MAY BRING TEMPO
RESTRICTIONS.
MARINE
THROUGH TUESDAY NIGHT...SOUTH TO SOUTHWEST INCREASING TODAY THROUGH
TUESDAY NIGHT AS A COLD FRONT APPROACHES THE WATERS. PERIODS OF SCA
CONDITIONS ARE LIKELY, ESPECIALLY OVER THE WATERS EAST OF PORTLAND,
WHERE WIND GUSTS WILL BE AROUND 25 KT AT TIMES WITH SEAS BUILDING TO
5-6KT. FOR THE NEARSHORE WATERS SOUTH OF PORTLAND, A SHORT DURATION
OF WIND GUSTS UP TO 25 KT IS POSSIBLE INTO THIS EVENING. STRONG TO
SEVERE OFFSHORE-MOVING THUNDERSTORMS ARE POSSIBLE TUESDAY EVENING
INTO TUESDAY NIGHT.
WINDS AND SEAS GENERALLY STAY BELOW SCA THRESHOLDS WEDNESDAY
INTO SATURDAY. OFFSHORE WINDS PREVAIL WEDNESDAY AND TURN SW
AHEAD OF A FRONT THURSDAY. WINDS TURN BACK OFFSHORE FRIDAY.
GYX WATCHES/WARNINGS/ADVISORIES
ME...HEAT ADVISORY FROM 11 AM TO 8 PM EDT TUESDAY FOR MEZ012>014-
018>021-023-024-033.
NH...HEAT ADVISORY FROM 11 AM TO 8 PM EDT TUESDAY FOR NHZ002>015.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT WEDNESDAY FOR ANZ150-152.
SMALL CRAFT ADVISORY FROM 6 AM TUESDAY TO 6 AM EDT WEDNESDAY
FOR ANZ151.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ154.
DISCUSSION...COMBS/SCHROETER
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page