430
FXUS61 KGYX 280701
AFDGYX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
301 AM EDT MON JUL 28 2025
SYNOPSIS
HIGH PRESSURE OVERHEAD TODAY INTO TUESDAY WILL BRING HOT
TEMPERATURES TO THE REGION. A STRONG COLD FRONT IS EXPECTED TO
APPROACH THE REGION WEDNESDAY...BRINGING THE THREAT FOR SHOWERS
AND THUNDERSTORMS. THIS WILL USHER IN COOLER AND DRIER AIR TO
END THE WEEK.
NEAR TERM /THROUGH TODAY/
KEY MESSAGES:
* DENSE FOG THIS MORNING THINS THROUGH THE 8AM/9AM HOURS
* EARLY WEEK HOT WEATHER BEGINS TODAY WITH HIGHS IN THE UPPER
80S AND LOWER 90S.
DENSE FOG DURING THE OVERNIGHT HOURS WILL WHITTLE AWAY EARLY
THIS MORNING, BUT LOW CLOUD DECKS MAY TAKE A COUPLE HOURS TO
FULLY RETREAT. OTHER THAN PLAYING WITH MORNING HEAT FLUX, THESE
SHOULDN'T HAVE MUCH LASTING IMPACT ON THE EXPECTED HOT
TEMPERATURES TODAY.
SURFACE TEMPERATURES WILL RISE INTO THE 80S THROUGH THE MORNING
HOURS, TOPPING IN THE UPPER 80S TO LOWER 90S FOR THE DAY. THIS
IS SUPPORTED BY 850MB TEMPS IN THE 16-18 C RANGE. FOR TODAY AT
LEAST, A LIGHT NW BREEZE WILL KEEP THE AIR SOMEWHAT DRIER, AND
THIS WILL LIMIT HEAT INDEX VALUES BELOW HEAT ADVISORY CRITERIA
FOR TODAY. A SEABREEZE PUSHES ONSHORE EARLY THIS AFTERNOON,
LIKELY PROVIDING A COUPLE DEGREE RELIEF ALONG THE IMMEDIATE
COAST.
DESPITE A DRY COLUMN ALOFT, HAVE INTRODUCED THE MENTION OF
ISOLATED SHOWERS ALONG THE SOUTHERN COAST INTO THE INTERIOR.
THIS IS JUST DURING A FEW HOURS THIS AFTERNOON. WITH THIN
MOISTURE IN THE LOW LEVELS BUILDING CU TODAY COMBINED WITH
CONVERGENCE FROM THE SEABREEZE AND OFFSHORE INLAND WINDS, SOME
OF THESE CU MAY BECOME DEEP ENOUGH TO SUPPORT A BRIEF SHOWER.
THIS IS SUPPORTED BY A VARIETY OF CAM SOLUTIONS WITH BUILDING
CAPE AND EVEN LOW/MID LEVEL LAPSE RATES OF 6 DEG C/KM OR HIGHER.
LOW SHEAR VALUES AND DRY AIR ALOFT WILL KEEP THESE ISOLATED AND
FOR THE MOST PART, TAME. HOWEVER, ONE OR TWO STRONGER SHOWERS
MAY BRING BRIEF PERIODS OF GUSTY WINDS SHOULD TALLER STRUCTURES
DEVELOP.
SHORT TERM /TONIGHT THROUGH 6 PM TUESDAY/
ANY CUMULUS THAT DEVELOPED DURING THE DAYTIME SHOULD QUICKLY
DISSIPATE INTO THE EVENING AND OVERNIGHT HOURS WITH A MOSTLY
CLEAR NIGHT FORECAST. EXCEPTION WILL BE FOR SOME HIGH CIRRUS AND
VALLEY/COASTAL STRATUS/FOG. OVERNIGHT TEMPERATURES COOL WELL
GIVEN THE WARM PATTERN, WITH OVERNIGHT LOWS IN THE 60S.
ATTENTION TURNS TOWARDS LIKELY THE WARMEST DAY OF THE WEEK ON
TUESDAY. 850MB TEMP RANGE INCREASES WITH VALUES LARGELY BETWEEN 17-19
C FROM THE MOUNTAINS SOUTH AND COASTWARD. THIS TRANSLATES TO
SURFACE TEMPS RISING INTO THE MID TO UPPER 90S FOR MUCH OF THIS
REGION. WEST WINDS IN THE MORNING HELP INCREASE THESE VALUES
QUICK, AND A SHIFT NW INTO THE AFTERNOON MAY BE JUST ENOUGH TO
KEEP GREATER HUMIDITY AT BAY. THIS KEEPS HEAT ADVISORY
CONDITIONS OF 95 HEAT INDEX OR HIGHER REGULATED TO SOUTH CENTRAL
AND SOUTHEASTERN NH. WILL BE KEEPING AN EYE ON DEW POINT TRENDS
INTO FAR SOUTHERN ME, NAMELY YORK CO, FOR ANY NEED OF EXPANSION.
LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/
..HIGH IMPACT WEATHER
* POTENTIAL EXISTS FOR SEVERE WEATHER ON WEDNESDAY
* QUIET WEATHER EXPECTED FOR REMAINDER OF FORECAST PERIOD
UNLESS FRONTAL BOUNDARY STALLS CLOSER TO SOUTHERN NH BY
LATE THIS WEEK
FORECAST PERIOD BEGINS WITH 500MB HEIGHT FALLS ON TUESDAY NIGHT AS
THE 500MB SHORTWAVE TROUGH APPROACHES FROM OTTAWA PROVINCE. THIS
FEATURE IS EXPECTED TO BE ANOMALOUS, WHICH WILL SUPPORT A STRONG JET
STREAK WITH IT FOR LATE JULY. WILL SEE IF THIS 100+KT JET WILL HAVE
ANY IMPACT ON THE SEVERE THREAT ON WEDNESDAY. CURRENTLY TIMING OF
THE ASSOCIATED SURFACE COLD FRONT IS ALIGNED SOMEWHAT WITH PEAK
HEATING ON WEDNESDAY AFTERNOON. MODEL GUIDANCE ENSEMBLE MEANS HAVE
HIGH PROBABILITY OF 1500 J/KG ACROSS SOUTHERN AREAS, SO WILL HAVE TO
WATCH TO SEE HOW THE THUNDERSTORM THREAT DEVELOPS. THESE STORMS WILL
BE THE HIGHEST CHANCE FOR RAINFALL FOR MOST AREAS FOR THE FORECAST
PERIOD. MANY AREAS ARE IN DESPERATE NEED FOR RAIN AS KBDI VALUES
CONTINUE TO INCREASE. COOLER AND LESS HUMID AIR WILL MOVE INTO THE
AREA ON THURSDAY AS A LARGE SURFACE HIGH PRESSURE CENTERED OVER THE
GREAT LAKES BEGINS TO NOSE INTO NORTHERN NEW ENGLAND. LOOKING AT THE
NBM/DESI PROBABILITIES, THERE IS A CHANCE THAT THE FRONT COULD GET
HUNG UP A LITTLE FURTHER NORTH WITH RAIN REACHING SOUTHERN NH IN THE
LATE THURSDAY THROUGH FRIDAY TIME PERIOD. TROUGH AXIS SWINGS
THROUGH FRIDAY NIGHT THROUGH SATURDAY, BRINGING THE POTENTIAL FOR
ANOTHER VERY COMFORTABLE SATURDAY. TEMPERATURES WILL BE ON THE
UPSWING BY SUNDAY, BUT IT WILL REMAIN CLEAR AND DRY WITH THE SURFACE
RIDGE EXPECTED TO BE DIRECTLY OVERHEAD. OVERALL EXPECT PRECIPITATION
TO BE BELOW NORMAL WITH NEAR NORMAL TEMPERATURES THROUGH THIS
PERIOD.
AVIATION /06Z MONDAY THROUGH FRIDAY/
SHORT TERM...DENSE FOG BRINGS LOW VISIBILITY AND CEILINGS TO
MOST COASTAL AND INTERIOR TERMINALS THROUGH EARLY MON MORNING.
FOG WILL BEGIN TO DISSIPATE AFTER SUNRISE, BUT LIFR TO IFR DECKS
MAY PERSIST UNTIL EARLY/MID MORNING. VFR AFTER, WITH SOME CU
DEVELOPMENT INTO THE AFTERNOON. CAN'T RULE OUT A FEW SHRA FOR
SOUTHERN ME TERMINALS THIS AFTERNOON. FOG AND LOW STRATUS RETURN
TONIGHT, BUT SPREAD SHOULD BE CONSTRAINED TO INTERIOR VALLEYS
AND A SMALLER FOOTPRINT ALONG THE COAST VS. SUNDAY NIGHT. VFR
TUESDAY WITH BREEZY NW WINDS.
LONG TERM...FOG TUESDAY NIGHT IN A HUMID AIRMASS IS POSSIBLE
BEFORE THUNDERSTORM POTENTIAL DURING THE DAY ON WEDNESDAY THAT
COULD BRING BRIEF IMPACTS TO AVIATION OPERATIONS. AVIATION
WEATHER LOOKS FAVORABLE FROM THURSDAY ONWARD WITH DRIER AND AND
NO LEVEL STRATUS EXPECTED.
MARINE
SHORT TERM...CONDITIONS WILL NOT MEET SCA CRITERIA TODAY THROUGH
TUESDAY. HIGH PRESSURE DRIFTS OVERHEAD KEEPING SEA 1 TO 2 FT AND
WINDS LARGELY SW AFTER A WIND SHIFT THIS MORNING. THE WARM
AIRMASS OVER COOL GULF OF MAINE WATERS WILL LIKELY RESULT IN
AREAS OF FOG, DENSE AT TIMES, OVER THE NEXT 36 HOURS.
LONG TERM...SOUTHWEST RETURN FLOW EXPECTED OVER THE COASTAL
WATERS BY WEDNESDAY AHEAD OF AN APPROACHING COLD FRONT. HIGH
MOISTURE COULD LEAD TO THE POTENTIAL FOR SOME MARINE FOG ON THE
MID-COAST. THUNDERSTORMS COULD BE POSSIBLE ON THE COASTAL WATERS
WEDNESDAY AFTERNOON. HIGH PRESSURE BECOMES DOMINATE BY THURSDAY
WITH CONDITIONS EXPECTED TO REMAIN BELOW SCA, BUT THE
POSSIBILITY OF EAST WINDS WILL EXIST THROUGH FRIDAY NIGHT.
GYX WATCHES/WARNINGS/ADVISORIES
ME...NONE.
NH...HEAT ADVISORY FROM 11 AM TO 8 PM EDT TUESDAY FOR NHZ008-010-
012>015.
MARINE...NONE.
NEAR TERM...CORNWELL
SHORT TERM...CORNWELL
LONG TERM...DUMONT
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page