586
FXUS61 KBOX 182256
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
556 PM EST TUE NOV 18 2025
SYNOPSIS
HIGH PRESSURE BUILDS OVERHEAD FOR WEDNESDAY AND THURSDAY,
BRINGING RELATIVELY LIGHT WINDS AND CONTINUED SEASONABLE
TEMPERATURES. A COLD FRONT WILL BRING A PERIOD OF UNSETTLED
WEATHER FRIDAY, WHICH MAY LINGER INTO SATURDAY, THEN HIGH
PRESSURE RETURNS NEXT SUNDAY.
NEAR TERM /THROUGH WEDNESDAY/
KEY MESSAGES:
* DRY WITH BELOW NORMAL TEMPERATURES AND INCREASING CLOUDS
TOWARDS THE SOUTH COAST
THE WIND FINALLY DIES OFF AFTER SUNSET THIS EVENING AS HIGH
PRESSURE BUILDS OVERHEAD. A LOW PRESSURE PASSES BY TO OUR SOUTH
LATE TONIGHT BUT WE SHOULDN'T SEE MUCH MORE THAN INCREASED
CLOUD COVER, WITH RAIN STAYING WELL TO THE SOUTH WITH TOO MUCH
DRY AIR OVER SOUTHERN NEW ENGLAND. GOOD RADIATIONAL COOLING
CONDITIONS UNTIL THE CLOUDS ARRIVE, SO THERE SHOULD AT LEAST BE
A FEW HOURS TO PERMIT TEMPERATURES TO REACH BELOW NORMAL LEVELS.
SHORT TERM /WEDNESDAY NIGHT/
KEY MESSAGES:
* MAINLY DRY WITH BELOW NORMAL TEMPERATURES.
CLEARING SKIES AS A PASSING LOW PRESSURE MOVES OFFSHORE DURING
THE MORNING HOURS. MORE CLOUDS EXPECTED TO RETURN LATER
WEDNESDAY NIGHT AS ANOTHER LOW PRESSURE TAKES A SIMILAR TRACK.
DRY WEATHER EXPECTED TO PREVAIL WITH A WEAK HIGH PRESSURE AND
ABUNDANT DRY AIR IN PLACE. NOT AS WINDY WEDNESDAY INTO WEDNESDAY
NIGHT.
LONG TERM /THURSDAY THROUGH TUESDAY/
KEY MESSAGES:
* NO IMPACTFUL WEATHER EXPECTED.
DRY CONDITIONS AND LIGHT WINDS CONTINUE THURSDAY WITH SURFACE
HIGH PRESSURE REMAINING POSITIONED ACROSS THE REGION.
TEMPERATURES WILL REMAIN SEASONABLY COOL WITH HIGHS IN THE MID
TO UPPER 40S.
ENSEMBLE GUIDANCE CONTINUES TO AGREE ON A NORTHERN STREAM
SHORTWAVE TROUGH TRACKING TO THE NORTH OF THE REGION FRI-SAT.
WEAK WARM ADVECTION AND SW FLOW AHEAD OF THE TROUGH WILL BRING
IN WARMER TEMPERATURES WITH HIGHS IN THE UPPER 40S FOR THE
HIGHER TERRAIN AND LOW-MID 50S ELSEWHERE. A PLUME OF SLIGHTLY
ABOVE NORMAL MOISTURE PUSHES ACROSS THE REGION FOR DURING THE
DAY. THIS WILL BE SUFFICIENT ENOUGH TO SUPPORT SOME SCATTERED
SHOWERS FRI/FRI NIGHT. EXACT TIMING IS STILL UNCERTAIN, BUT
MODEL GUIDANCE IS IN GOOD AGREEMENT WITH THIS BEING A LOW QPF
EVENT. RECENT RUNS HAVE TRENDED DOWNWARD IN AMOUNTS. OVERALL,
LOOKING LIKE A RANGE FROM A TRACE TO 0.25". CAN'T RULE OUT LIGHT
SNOW SHOWERS/FLAKES MIXING IN FOR THE HIGHER ELEVATIONS OF
NORTHERN MA IF ANY SHOWERS DEVELOP EARLY FRI OR LATER FRI
NIGHT/EARLY SAT AM.
A COLD FRONT WILL ACCOMPANY THE TROUGH PASSAGE SATURDAY NIGHT,
BRINGING IN COOLER TEMPERATURES ALOFT. FAIRLY ZONAL FLOW ALOFT
SATURDAY WITH HIGH PRESSURE BUILDING IN. THIS WILL BRING DRY AND
COOLER WEATHER FOR SATURDAY WITH HIGHS IN THE LOW TO UPPER 40S.
SIMILAR CONDITIONS PREVAIL SUNDAY WITH THE SAME PATTERN
OVERHEAD.
EARLY NEXT WEEK, ENSEMBLE GUIDANCE AGREES WITH GENERALLY ZONAL
ALOFT ALOFT OVER THE REGION WITH A FEW WEAK WAVES EMBEDDED IN
THE FLOW. TIMING AND MOISTURE AVAILABILITY VARY ACROSS SOLUTIONS
WITH SOME SHOWING POTENTIAL FOR LIGHT PRECIPITATION.
TEMPERATURES WILL LIKELY LEAN CLOSE TO NORMAL IN THE MID/UPPER
40S TO NEAR 50 DEGREES.
AVIATION /00Z WEDNESDAY THROUGH SUNDAY/
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
TONIGHT... HIGH CONFIDENCE.
VFR. LIGHT WESTERLY WINDS UNDER 10 KNOTS
WEDNESDAY AND WEDNESDAY NIGHT...HIGH CONFIDENCE.
VFR. NW TO NNW WIND LESS THAN 10 KNOTS. SHOWERS POSSIBLE AT ACK
WED MORNING, OTHERWISE DRY FOR THE REST OF THE REGION.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.
VFR. WESTERLY WINDS AROUND 10 KNOTS.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
VFR. LIGHT WESTERLY WINDS AROUND 5 KNOTS.
OUTLOOK /THURSDAY THROUGH SUNDAY/...
THURSDAY: VFR.
THURSDAY NIGHT: MAINLY VFR, WITH LOCAL MVFR POSSIBLE.
FRIDAY: MAINLY VFR, WITH LOCAL IFR POSSIBLE. BREEZY. SLIGHT
CHANCE RA.
FRIDAY NIGHT: MAINLY VFR, WITH LOCAL MVFR POSSIBLE. SLIGHT
CHANCE RA.
SATURDAY: VFR. SLIGHT CHANCE RA.
SATURDAY NIGHT THROUGH SUNDAY: VFR.
MARINE
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
THROUGH WEDNESDAY NIGHT...HIGH CONFIDENCE.
A WEAK LOW PRESSURE PASSES SOUTH OF THE WATERS LATE TONIGHT INTO
WEDNESDAY MORNING. A FEW EARLY MORNING SHOWERS ARE POSSIBLE FOR
THE WATERS SOUTH OF THE ISLANDS, BUT EXPECTING MOST OF THE
WATERS TO REMAIN DRY WITH GOOD VISIBILITY. WEAK HIGH PRESSURE
OVER THE WATERS LEADS TO RATHER LIGHT WINDS AND SEAS WEDNESDAY
THROUGH WEDNESDAY NIGHT.
OUTLOOK /THURSDAY THROUGH SUNDAY/...
THURSDAY THROUGH THURSDAY NIGHT: WINDS LESS THAN 25 KT.
FRIDAY: WINDS LESS THAN 25 KT. SLIGHT CHANCE OF RAIN.
FRIDAY NIGHT: WINDS LESS THAN 25 KT. AREAS OF SEAS APPROACHING
5 FT. CHANCE OF RAIN.
SATURDAY THROUGH SATURDAY NIGHT: WINDS LESS THAN 25 KT. SEAS
LOCALLY APPROACHING 5 FT. SLIGHT CHANCE OF RAIN.
SUNDAY: WINDS LESS THAN 25 KT.
BOX WATCHES/WARNINGS/ADVISORIES
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR ANZ250-
254>256.
SYNOPSIS...BELK/MENSCH
NEAR TERM...BELK
SHORT TERM...BELK
LONG TERM...MENSCH
AVIATION...KP
MARINE...BELK/MENSCH
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