578
FXUS61 KGYX 211831
AFDGYX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
231 PM EDT FRI AUG 21 2026
WHAT HAS CHANGED
NO SIGNIFICANT CHANGES TO THE FORECAST WERE NEEDED.
KEY MESSAGES
1. MAINLY DRY WEATHER CONTINUES THROUGH TONIGHT WITH COOLER AND
UNSETTLED WEATHER THIS WEEKEND.
2. A SLOW MOVING SYSTEM WILL CONTINUE SHOWER CHANCES INTO EARLY
TO MID WEEK, WITH WIDESPREAD MEASURABLE RAINFALL UNLIKELY.
DISCUSSION
KEY MESSAGE 1 DESCRIPTION...
MOSTLY DRY CONDITIONS ARE EXPECTED TO CONTINUE THROUGH TONIGHT AS
HIGH PRESSURE SITS OVERHEAD THIS AFTERNOON. THE HIGH WILL THEN BEGIN
SHIFTING TO THE NORTHEAST TONIGHT AS IT GIVES WAY TO MULTIPLE LOW
PRESSURES THAT WILL MOVE ACROSS NORTHERN NEW ENGLAND THIS WEEKEND.
FOR TONIGHT, OTHER THAN THE COAST AND SOUTHERN NH, SKIES SHOULD STAY
MAINLY CLEAR, ALLOWING TEMPERATURES TO FALL INTO THE 50S
SOUTH OF THE MOUNTAINS WITH SOME 40S TO THE NORTH. MORE VALLEY FOG
IS LIKELY ALONG THE CT RIVER, AND I DO HAVE SOME LOW POPS (20%) IN
SOUTHEAST NH AS SOME MODELS INDICATE A FEW SHOWERS ARE POSSIBLE
OVERNIGHT.
THE FIRST LOW THEN APPROACHES FROM THE SOUTH SATURDAY MORNING WITH
SKIES BECOMING MOSTLY CLOUDY, GENERALLY IN A SOUTH TO NORTH
PROGRESSION THROUGH THE DAY AS THE LOW CARRIES HIGHER MOISTURE INTO
THE AREA. IT WILL ALSO BRING SCATTERED SHOWERS (WITH DRY PERIODS AS
WELL), ALTHOUGH MODELS HAVE BEEN STRUGGLING ON A RUN TO RUN BASIS
REGARDING TIMING, COVERAGE, AND LOCATION OF SHOWERS. LOOKING AT
LATEST GUIDANCE, GLOBAL MODELS INDICATE BROAD LIFT OVER THE GULF OF
MAINE APPROACHING THE COAST AND SOUTHEAST NH IN THE MORNING AND
EARLY AFTERNOON, WHICH WILL THE PRIMARY AREAS TO WATCH FOR SHOWERS.
LIFT SPREADS NORTHWARD THROUGH THE AFTERNOON AND EVENING
(MOSTLY ACROSS WESTERN ME), BRINGING INCREASING CHANCES FOR
SHOWERS, AND THE 12Z NAMNEST AND HRRR ARE GENERALLY ON BOARD
WITH THIS SCENARIO. RAINFALL ACCUMULATIONS ARE EXPECTED TO
REMAIN LIGHT, BUT PARTS OF WESTERN ME COULD PICK UP OVER 0.25"
OF RAIN THROUGH SATURDAY EVENING.
MORE UNCERTAINTY EXISTS SATURDAY NIGHT INTO SUNDAY MORNING. SOME
MODELS FAVOR A LULL IN THE SHOWERS DUE TO SOME MID-LEVEL
DRYING WHILE THE LOW-LEVELS REMAIN NEARLY SATURATED, SUGGESTING FOG
(POSSIBLY DENSE) AND PRECIPITATION THAT FALLS MORE IN THE FORM OF
DRIZZLE. OTHERS INDICATE ANOTHER WAVE OF LOW PRESSURE, WHICH WOULD
BRING MORE IN THE WAY OF SHOWERS AND LESS IN THE WAY OF FOG. DUE TO
THE UNCERTAINTY, POPS OF 20-40% CONTINUE TO BE ADVERTISED.
SUNDAY REMAINS CLOUDY AND DREARY FOR MOST WITH SCATTERED SHOWERS
POSSIBLE AT TIMES IN THE MORNING. ANOTHER LOW PRESSURES TRACKS
ACROSS QUEBEC THAT WILL SEND A COLD FRONT IN FROM THE WEST,
RESULTING IN ANOTHER INCREASE IN SHOWER CHANCES AND POSSIBLY A STORM
OR TWO IN THE AFTERNOON AND EVENING HOURS. SOME SHOWERS CONTINUE
INTO SUNDAY NIGHT, BUT THESE SHOULD DIMINISH SOUTH OF THE MOUNTAINS
FROM WEST TO EAST OVERNIGHT BEHIND THE FRONT.
KEY MESSAGE 2 DESCRIPTION...
CLOSED LOW MOVING EAST OF THE GREAT LAKES WILL CONTINUE TO
PIVOT INTO SOUTHERN QUEBEC MONDAY. SHOWERS IN THE MORNING EXIT
NORTHEAST ACROSS SOUTHERN ME, WITH THINNING CLOUDS ACROSS NH. AN
EMBEDDED WAVE IN THE LOW'S CIRCULATION WILL LIFT NORTH THROUGH
THE MORNING, WITH BUILDING INSTABILITY THROUGH MID AFTERNOON.
THIS COULD RESULT IN A REJUVENATED SHOWER/THUNDERSTORM CHANCE.
THE THUNDERSTORM PARAMETER SPACE HAS SOME INGREDIENTS GOING FOR
IT, BUT ALSO LIMITATIONS. 0-6KM SHEAR OF AROUND 50 KTS IS
ABUNDANT ON THE PERIPHERY OF THE BROAD LOW, AND THIS OVERLAPS
WITH MARGINAL SURFACE CAPE EARLY MONDAY. LOW AND MID LEVEL LAPSE
RATES WOULD BOTH BE SUPPORTIVE OF CONVECTION, HOWEVER ITS
POSSIBLE DRY AIR ALOFT WILL HAVE INCREASED SIGNIFICANTLY. WILL
KEEP THE MENTION OF ISO TO SCT SHOWERS/THUNDER IN THE FORECAST
AT THIS TIME.
TUESDAY MAY SEE FURTHER INFLUENCE OF THE CLOSED LOW, WITH A
RETURN OF MOISTURE PRODUCING A CONTINUATION OF CLOUD COVER WITH
THE CHANCE OF SHOWERS. THESE SHOWERS TAKE ADVANTAGE OF DAYTIME
HEATING, LIKELY MORE DIURNALLY DRIVEN THAN ASSOCIATED WITH A
FRONT. THEY MAY ALSO BE MORE WIDESPREAD THAN THE CURRENT
FORECAST CARRIES, BUT WILL SEE HOW TIMING AND INFLUENCE OF THE
CLOSED LOW TRENDS. THE LOW FINALLY LOSES ITS GRASP ON NEW
ENGLAND COME MIDWEEK AS IT NUDGES NORTHEAST INTO THE CANADIAN
MARITIMES. THIS WOULD PROVIDE A BREAK FROM THE DREARY CONDITIONS
AS TEMPERATURES REMAIN SEASONABLE.
AVIATION /18Z FRIDAY THROUGH WEDNESDAY/
THROUGH 18Z SATURDAY...VFR THE REST OF THE DAY TODAY AND AT LEAST
INTO THE FIRST PART OF TONIGHT. LIFR TO IFR VALLEY FOG IS LIKELY AT
HIE AND LEB AGAIN TONIGHT WITH THE FORECAST MORE UNCERTAIN
ELSEWHERE. SOUTHERN NH AND COASTAL TERMINALS MAY START SEEING MVFR
TO IFR CEILINGS AS EARLY AS OVERNIGHT INTO SATURDAY MORNING AS
WELL AS A FEW SHOWERS. HOWEVER, IT'S POSSIBLE RESTRICTIONS HOLD OFF
UNTIL BEYOND THE TAF PERIOD, SO THESE HAVE BEEN LEFT OUT OF THE TAFS
DUE TO UNCERTAINTY.
OUTLOOK:
REST OF SATURDAY-SATURDAY NIGHT: INCREASING CHANCES FOR SHOWERS, AND
A LOWERING OF CEILINGS FROM SOUTH TO NORTH IS LIKELY WITH MANY SITES
REACHING AT LEAST IFR, BUT LIFR IS POSSIBLE, ESPECIALLY GOING INTO
SATURDAY NIGHT. FOG IS ALSO LIKELY SATURDAY NIGHT. TIMING OF
RESTRICTIONS REMAINS UNCERTAIN, BUT MOST LIKELY TIME TO START SEEING
IFR IS SATURDAY AFTERNOON INTO SATURDAY EVENING.
SUNDAY: FOG LIFTS IN THE MORNING, EXCEPT MAY LINGER AT RKD MUCH OF
THE DAY. CEILINGS MAY REMAIN IFR TO EVEN LIFR FOR MOST SITES,
ESPECIALLY IN WESTERN ME, ALTHOUGH NH TERMINALS COULD REACH
MVFR BY THE AFTERNOON. SHOWERS REMAIN LIKELY OVER MUCH OF NEW
ENGLAND.
SUNDAY NIGHT: IFR TO LIFR RESTRICTIONS REMAIN LIKELY DUE TO
FOG, LOW STRATUS AND SHOWERS. SOME IMPROVEMENT FROM WEST TO EAST
IS POSSIBLE OVERNIGHT, BUT THAT REMAINS UNCERTAIN.
MONDAY: MVFR CIGS POSSIBLE, IMPROVING TOWARDS VFR AS THE DAY
CONTINUES. SHRA POSSIBLE ACROSS THE INTERIOR.
MONDAY NIGHT: LESS SHRA CHANCES, VFR TO MVFR CIGS
TUESDAY: SHRA DEVELOP DURING THE DAY WITH MVFR CIGS POSSIBLE AS
A CLOSED LOW MOVES OVERHEAD.
TUESDAY NIGHT AND WEDNESDAY: IMPROVEMENT TO VFR WITH NO SIG WX.
MARINE
THROUGH SUNDAY NIGHT...HIGH PRESSURE WILL LIFT NORTHEAST OF THE
WATERS THROUGH TONIGHT AS MULTIPLE WEAK LOW PRESSURES OR
SURFACE TROUGHS APPROACH FROM THE SOUTH AND MOVE ACROSS THE
WATERS THIS WEEKEND, BRINGING INCREASE CHANCES FOR SHOWERS AND
FOG. NORTHEAST WINDS MAY BRIEFLY APPROACH SCA LEVELS SATURDAY
BUT ARE OTHERWISE EXPECTED STAY BELOW SCA LEVELS. ANOTHER LOW
CROSSES QUEBEC SUNDAY NIGHT AND IS EXPECTED TO SEND A COLD
FRONT INTO THE WATERS OVERNIGHT AND TOWARD DAYBREAK MONDAY.
CLOSED AREA OF LOW PRESSURE WILL PUSH TOWARDS NEW ENGLAND INTO
THE BEGINNING OF NEXT WEEK BRINGING A BROAD WIND FIELD. GUSTS
SHOULD REMAIN BELOW SCA CRITERIA, BUT EXPECT GRADUALLY BUILDING
WAVES 2 TO 4 FT THROUGH MIDWEEK.
GYX WATCHES/WARNINGS/ADVISORIES
ME...NONE.
NH...NONE.
MARINE...NONE.
DISCUSSION...COMBS/CORNWELL
AVIATION...COMBS
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