100
FXUS61 KGYX 180639
AFDGYX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAY ME
239 AM EDT FRI SEP 18 2026
WHAT HAS CHANGED
LITTLE CHANGE TO THE GOING FORECAST EARLY THIS FRIDAY MORNING.
KEY MESSAGES
1. ANY SHOWERS END PRIOR TO SUNRISE THIS MORNING. AREAS OF FOG
WILL LIFT QUICKLY AS MIXING COMMENCES. HIGH PRESSURE MOVES IN
FOR TONIGHT AND SATURDAY WITH FAIR WEATHER. AREAS OF OF FROST
POSSIBLE IN MOUNTAIN VALLEYS IN THE NORTH TONIGHT.
2. COOLER THAN NORMAL TEMPERATURES ARE EXPECTED NEXT WEEK. THE
FRONT TO OUR SOUTH WILL PROVIDE THE FOCUS FOR RAIN CHANCES
DURING THE EARLY PART OF THE WEEK.
DISCUSSION
KEY MESSAGE 1 DESCRIPTION...
A COLD FRONT AND ASSOCIATED WEAK LOW PRESSURE WILL MOVE EAST OF
THE FORECAST AREA EARLY THIS MORNING. THE SHOWERS ARE LIKELY TO
MOVE OFFSHORE WELL BEFORE SUNRISE. THEREAFTER, CLEARING QUICKLY
TAKE PLACE ALONG WITH THE QUICK DISSIPATION OF ANY FOG. THE
BALANCE OF THE DAY WILL FEATURE WARM TEMPERATURES, MOSTLY SUNNY
SKIES, AND WIND GUSTS OF 20 TO 25 MPH FROM THE NW.
SFC HIGH PRESSURE WILL IMPINGE ON THE FORECAST AREA FROM THE NW
TONIGHT WHICH WILL ALLOW THE WINDS TO BECOME LIGHT. PORTIONS OF
THE NORTHERN MOUNTAINS (VALLEYS) MAY DECOUPLE ENOUGH TO ALLOW
FOR RADIATIONAL COOLING THAT DELIVERS LOWS IN THE 30S ALLOWING
POSSIBLE AREAS OF FROST. 40S ELSEWHERE.
THE SFC HIGH CRESTS OVER THE FORECAST AREA ON SATURDAY ALLOWING
FOR A LOT OF SUN, LIGHTER WINDS, AND COOLER HIGH TEMPERATURES.
KEY MESSAGE 2 DESCRIPTION...
THE HIGHEST CONFIDENCE PORTION OF THE EXTENDED IS THAT THE
PATTERN WILL GENERALLY FAVOR HIGH PRESSURE LOCALLY THRU NEXT
WEEK. MORE THAN THAT HIGH PRESSURE IS LOOKING SEASONABLY STRONG.
ABSENT ANY CLOUD COVER THAT WILL MEAN RELATIVELY SHALLOW MIXING
DURING THE DAY, AND OVERNIGHT IDEAL CONDITIONS FOR RADIATIONAL
COOLING. THE LATEST RUN OF THE NBM HAS DAYTIME TEMPS COOLER THAN
NORMAL, STAYING IN THE 60S, WHILE OVERNIGHT PLENTY OF 40S AND
MID TO UPPER 30S IN THE USUAL COLDER VALLEYS. I SUSPECT FROST
WILL BE POSSIBLE, BUT THAT WILL BE DEPENDENT ON ANY CLOUD COVER
ON INDIVIDUAL NIGHTS. I DO NOT PLAN TO PUT ANY IN THE FORECAST
AT THIS RANGE, BUT I WANT TO MENTION IT HERE AS A THREAT.
THE CLOUD COVER WILL BE TIED TO THE SURFACE BAROCLINIC ZONE. THE
HIGH PRESSURE SHOULD TEND TO KEEP THAT SOUTH OF THE FORECAST
AREA, BUT THAT DOES NOT MEAN THAT ANY WAVE TRACKING ALONG IT
CAN'T SPREAD CLOUDS AND EVEN RAIN/SHOWERS THRU PARTS OF THE
AREA. GIVEN THE STRONG RIDGE CENTERED ACROSS THE SOUTHEASTERN
CONUS, THE PATTERN IS FAIRLY FAVORABLE FOR A LATER SEASON RING
OF FIRE. SO THE CONVECTIVE CYCLE COULD DRIVE THESE WAVES, AND
WILL LEAD TO LOWER THAN NORMAL MODEL CONFIDENCE. RIGHT NOW
ENSEMBLE GUIDANCE LIKES ONE OF THESE WAVES TO PASS NEAR THE
FORECAST AREA SUN. THE LATEST ECMWF ENS HAS ROUGHLY A THIRD OF
THE MEMBERS DRY FOR THE NORTHEASTERN HALF OF THE FORECAST AREA,
AND THE GEFS HAS NEAR A 50/50 SPLIT. THE LATEST NBM RUN HAS AN
AREA OF LIKELY POP SWEEPING ALONG AND SOUTH OF A LEB TO PWM
LINE, SO THAT IS A FAIRLY GOOD MATCH AND I SEE NO REASON TO
ALTER IT. ENSEMBLES ARE ALSO LIGHTER ON QPF THAN THE ONGOING
EVENT. WE WILL WELCOME THE RAIN BUT IT DOES NOT LOOK LIKE A
DROUGHT BUSTER.
AVIATION /00Z FRIDAY THROUGH TUESDAY/
ANY LOWER CIGS AND VSBYS EARLY THIS MORNING IMPROVE BETWEEN 09Z
AND 13Z WITH THE PASSAGE OF A COLD FRONT. VFR EXPECTED FOR THE
REST OF THE DAY WITH NW WIND GUSTS OF 20 TO 25 KT AT TIMES. VFR
TONIGHT WITH VALLEY FOG, MAINLY IN THE CT RIVER VALLEY. VFR WITH
LIGHTER WINDS ON SATURDAY WITH HIGH PRESSURE OVERHEAD.
OUTLOOK...
SATURDAY NIGHT: GENERALLY VFR EARLY WITH CEILINGS LOWERING
AFTER 06Z SUNDAY.
SUNDAY: AREAS OF MVFR EXPECTED, ESPECIALLY SOUTHWEST, WITH
RAIN/SHOWERS. VFR POSSIBLE NORTH.
MONDAY-TUESDAY: GENERALLY VFR EXPECTED. MVFR AND SHOWERS POSSIBLE
ESPECIALLY SOUTH. LOCAL IFR OR LOWER POSSIBLE OVERNIGHT IN
VALLEY FOG.
WEDNESDAY: VFR CONDITIONS EXPECTED. LOCAL IFR OR LOWER POSSIBLE
OVERNIGHT IN VALLEY FOG.
MARINE
A COLD FRONT WILL PASS ACROSS THE WATERS THIS MORNING. WIND
GUSTS AROUND 20 KT LIKELY, WITH A FEW AROUND 25 KT POSSIBLE.
TRANQUIL TONIGHT AND SATURDAY WITH HIGH PRESSURE OVERHEAD. WINDS
AND SEAS GENERALLY EXPECTED TO REMAIN BELOW SCA THRESHOLDS NEXT
WEEK. WILL HAVE TO WATCH FOR AREAS OF FOG DEVELOPING NEAR
FRONTAL BOUNDARY DURING THE FIRST HALF OF THE WEEK. SEAS MAY
BUILD TO NEAR 5 FT SOUTH OF CAPE ELIZABETH BY MIDWEEK.
GYX WATCHES/WARNINGS/ADVISORIES
ME...NONE.
NH...NONE.
MARINE...NONE.
DISCUSSION...EKSTER/LEGRO
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