903
FXUS61 KBOX 302348
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
648 PM EST TUE DEC 30 2025
WHAT HAS CHANGED
HIGH WIND WARNING HAS BEEN CONVERTED TO A WIND ADVISORY THROUGH
PREDAWN HOURS OF WEDNESDAY FOR THE HIGHER TERRAIN OF NORTHERN AND
WESTERN MASSACHUSETTS. PLUS, A WINTER WEATHER ADVISORY WAS ISSUED AT
NANTUCKET AND MARTHA'S VINEYARD IS IN EFFECT WEDNESDAY EVENING
THROUGH LATE THURSDAY MORNING, FOR SNOW AMOUNTS BETWEEN 2-4 INCHES.
ELSEWHERE, MINOR SNOW ACCUMULATIONS ARE EXPECTED, WHICH WILL LEAD TO
SLICK CONDITIONS NEW YEAR'S EVE INTO NEW YEAR'S DAY.
KEY MESSAGES
- STRONG WIND GUSTS CONTINUE TONIGHT WITH COLD TEMPERATURES AND
ISOLATED SNOW SHOWERS. DRY AND CHILLY WEDNESDAY.
- PERIOD OF SNOW NEW YEAR'S EVE INTO NEW YEAR'S DAY, FOLLOWED BY
A CHILLY FIRST DAY OF 2026.
- TEMPERATURES REMAIN BELOW NORMAL THROUGH THE REST OF THE WEEK
AND INTO THE START OF NEXT WEEK.
- VESSEL ICING DUE TO ACCRETION OF LIGHT FREEZING SPRAY OVER THE
WATERS IS POSSIBLE LATE THIS WEEK INTO THIS WEEKEND.
DISCUSSION
KEY MESSAGE 1...STRONG WIND GUSTS CONTINUE TONIGHT WITH COLD
TEMPERATURES AND ISOLATED SNOW SHOWERS. DRY AND CHILLY WEDNESDAY.
STRONG WESTERLY GUSTS 40-50 MPH CONTINUE THROUGH THE FIRST HALF OF
TONIGHT ACROSS SOUTHERN NEW ENGLAND. MINOR CHANGES TO THE FORECAST
AT THIS TIME, DROPPED THE HIGH WIND WARNING FOR INTERIOR SECTIONS OF
MASSACHUSETTS, WHICH WERE REPLACED WITH A WIND ADVISORY. CORE OF THE
STRONGEST WIND ALOFT SHIFTS AWAY FROM SOUTHERN NEW ENGLAND DURING
THE OVERNIGHT, EASING GUSTS BY DAYBREAK. OVERNIGHT IS STILL FAIRLY
COLD WITH MINIMUM TEMPERATURES IN THE TEENS AND LOWER 20S, THE FEELS
LIKE TEMPERATURE LOWERS INTO THE SINGLE DIGITS AND LOWER TEENS.
GIVEN THE PREVAILING WIND DIRECTION AND LAKE EFFECT SNOW ACROSS THE
EASTERN GREAT LAKES, CANNOT RULE OUT A FEW LIGHT SNOW SHOWERS ACROSS
WESTERN MASSACHUSETTS AND NORTHERN CONNECTICUT, OTHERWISE DRY.
DRY AND CHILLY CONDITIONS TO WRAP UP THE FINAL DAY OF 2025, BUT SNOW
IS ON THE HORIZON FOR THE NEW YEAR'S CELEBRATION, MORE ON THAT IN
THE NEXT KEY MESSAGE.
KEY MESSAGE 2...PERIOD OF SNOW NEW YEAR'S EVE INTO NEW YEAR'S DAY,
FOLLOWED BY A CHILLY FIRST DAY OF 2026.
THERE IS GROWING CONFIDENCE IN A PERIOD OF SNOW STARTING WEDNESDAY
EVENING AND ENDING THURSDAY MORNING, COINCIDING WITH NEW YEAR'S EVE
CELEBRATIONS. PLEASE PLAN ACCORDINGLY.
FOR MANY, THIS SHOULD BE A MINOR SNOW EVENT WITH SNOW AMOUNTS AROUND
ONE INCH, BUT THERE IS INCREASING ODDS FOR WIDESPREAD TOTALS BETWEEN
2-4 INCHES AT NANTUCKET, MARTHA'S VINEYARD, CAPE COD, AND SOUTHEAST
MASSACHUSETTS. THE SYNOPTIC FEATURES INCLUDE; POTENT 500MB SHORTWAVE
AND DEVELOPING SURFACE LOW-PRESSURE SYSTEM. THERE IS NOT A TON OF
MOISTURE TO BE HAD, INTERIOR LOCATIONS NEAR 0.25" AND 0.40" AT THE
COAST. REASONING FOR HIGHER TOTALS ACROSS THE AREAS MENTIONED ABOVE
IS DUE TO OCEAN ENHANCEMENT. SOUTHWEST FLOW OVER RELATIVELY WARMER
OCEAN WATERS ADDS A LEVEL OF INSTABILITY AND WITH ASSISTANCE OF SEA
AIR, SALT NUCLEATION TENDS TO SHIFT THE SNOW GROWTH LOWER THAN WHAT
WE'D SEE OVER LAND, CLOSER TO -10C. A BUFKIT FORECAST SOUNDING
INDICATES SATURATION BETWEEN -8C AND -12C AND WITHIN THE LAYER THERE
IS STRONG LIFT/OMEGA, THUS AN EFFECTIVE SNOW PRODUCER. ADDING TO OUR
CONFIDENCE, HREF PROBS FOR SNOWFALL RATES 1+ INCH/HR ARE 60-80% FOR
THE CAPE AND ISLANDS, WITH A 30% PROBABILITY OF RATES 2+ INCH/HR AT
NANTUCKET. NOW, CANNOT TAKE THIS VERBATIM, BUT SHOWS THE POTENTIAL
FOR HEAVY SNOWFALL BETWEEN MIDNIGHT AND 6AM.
OPT'D TO ISSUE A WINTER WEATHER ADVISORY DUE TO THESE CONDITIONS FOR
NANTUCKET AND MARTHA'S VINEYARD, 7PM WEDNESDAY TO 1PM THURSDAY, WITH
THE STEADIEST SNOW BETWEEN MIDNIGHT AND 6AM. HERE SNOWFALL AMOUNTS
ARE FORECAST 2-4". IT'S POSSIBLE THE ADVISORY EXPANDS INTO CAPE COD
AND SOUTHERN PLYMOUTH AND BRISTOL COUNTIES, BUT AT THIS TIME, HAVE
LOW CONFIDENCE IN TOTALS EXCEEDING 3".
SNOW ENDS MID TO LATE MORNING ON NEW YEARS DAY, FOLLOWED BY DRY AND
COLD TEMPERATURES IN THE 20S. BREEZY NORTHWEST WINDS WITH GUSTS 15
TO 25 MPH LEAD TO FEELS LIKE TEMPERATURES IN THE SINGLE DIGITS AND
TEENS.
KEY MESSAGE 3...TEMPERATURES REMAIN BELOW NORMAL THROUGH THE REST OF
THE WEEK AND INTO THE START OF NEXT WEEK.
A MID LEVEL TROUGH WILL CONTINUE TO SIT OVER QUEBEC AND THE
NORTHEASTERN US THROUGH THE WEEKEND. GUIDANCE REMAINS IN CONSENSUS
WITH THIS OVERALL PATTERN. AS A RESULT, THIS STRETCH OF BELOW NORMAL
TEMPERATURES WILL ONLY CONTINUE. 925 MB TEMPERATURES WILL REMAIN
BETWEEN -15C AND -10C THROUGH THE WEEKEND AND INTO THE START OF NEXT
WEEK. SURFACE HIGH PRESSURE WILL START TO CREEP IN FROM THE
SOUTHWEST, BUT A WEAK LOW FROM ONTARIO MAY ALSO PASS THROUGH
NORTHERN NEW ENGLAND SOMETIME THIS WEEKEND. ONLY A FEW MEMBERS OF
THE GUIDANCE HIGHLIGHT THAT BRIEF DISTURBANCE, THOUGH, AND
CONFIDENCE IN POSSIBLE IMPACTS TO SOUTHERN NEW ENGLAND IS LOW AT
THIS TIME. THE MAIN THING, THOUGH, WILL BE HIGH PRESSURE MOVING IN
TO KEEP THE REGION DRY AND COLD THROUGH MONDAY MORNING. HIGHS REMAIN
RELATIVELY UNCHANGED FROM TOMORROW THROUGH THE WEEKEND, GENERALLY
STAYING IN THE 20S AND LOW 30S. LOWS CONTINUE TO FALL INTO THE TEENS
AND SINGLE DIGITS. THERE MAY BE A SLIGHT IMPROVEMENT FOR MONDAY AS
THE TROUGH STARTS TO SHIFT OFF TO THE EAST AND SLIGHTLY WARMER AIR
GETS A CHANCE TO MOVE IN FROM THE SOUTH, BUT A SIGNIFICANT WARM-UP
IS NOT EXPECTED. NAEFS GUIDANCE HAS TEMPERATURES AROUND 2 STANDARD
DEVIATIONS BELOW AVERAGE THROUGH THE WEEKEND, IMPROVING TO AROUND 1
STANDARD DEVIATION BELOW NORMAL FOR THE START OF NEXT WEEK. SO, ANY
IMPROVEMENT WOULD BE QUITE MODEST.
WITH CONTINUED HIGH PRESSURE, THE REGION SHOULD REMAIN MOSTLY DRY
FROM FRIDAY ONWARD. SNOW SHOWERS SHOULD MOVE OUT OF THE REGION
HEADING INTO FRIDAY MORNING. CONFIDENCE DECREASES IN CHANCES FOR
ADDITIONAL PRECIPITATION FOR THE START OF NEXT WEEK AS GUIDANCE
VARIES SIGNIFICANTLY PAST MONDAY MORNING.
KEY MESSAGE 4...VESSEL ICING DUE TO ACCRETION OF LIGHT FREEZING
SPRAY OVER THE WATERS IS POSSIBLE LATE THIS WEEK INTO THIS WEEKEND.
MOSTLY FOR MARINE INTERESTS, BUT WITH A PROLONGED PERIOD OF COLD AIR
OVER THE RELATIVELY MILDER OCEAN WATERS, PERIODS OF FREEZING SPRAY
COULD ACCRETE ON VESSELS THROUGH THE FIRST WEEK OF JANUARY. IT
DOESN'T LOOK LIKE ANTICIPATED FREEZING SPRAY ON ANY PARTICULAR DAY
WOULD REACH THE MODERATE TO HEAVY ICING RATES, WHICH WOULD
NECESSITATE FREEZING SPRAY HEADLINES FOR THE WATERS. DAYS WHICH HAVE
LOWER SIGNIFICANT WAVE HEIGHTS WOULD HAVE A LESSER RISK. HOWEVER, WE
DID WANT TO GIVE IT AT LEAST A MENTION, SINCE THE RISK FOR LIGHT
VESSEL ICING DUE TO FREEZING SPRAY COULD EXIST FOR A PROLONGED
PERIOD GIVEN THE SPELL OF COLDER TEMPERATURES UPCOMING.
AVIATION /00Z WEDNESDAY THROUGH SUNDAY/
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
THROUGH WEDNESDAY: HIGH CONFIDENCE.
VFR. BKN CLOUDS 4-6K FT WITH A FEW FLURRIES SHOULD SCATTER OUT
THIS EVENING WITH BKN SCTRATO-CU REDEVELOPING WED. W GUSTS 25-35
KT GRADUALLY DIMINISHING TONIGHT WITH SW GUSTS AROUND 20 KT WED.
WEDNESDAY NIGHT: MODERATE CONFIDENCE.
CONDITIONS LOWERING TO MVFR WITH POCKETS OF IFR AS SNOW SHOWERS
DEVELOP, MAINLY AFTER MIDNIGHT. MINOR ACCUMULATIONS LIKELY,
ESPECIALLY ACROSS SE MA AND CAPE/ISLANDS.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK /WEDNESDAY NIGHT THROUGH SUNDAY/...
NEW YEARS DAY: VFR. BREEZY. SLIGHT CHANCE SN.
THURSDAY NIGHT THROUGH SATURDAY NIGHT: VFR. BREEZY.
SUNDAY: VFR.
MARINE
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
TONIGHT THROUGH WEDNESDAY...HIGH CONFIDENCE.
GALE-FORCE WESTERLY WIND GUSTS UP TO 40 KT ARE EXPECTED INTO TONIGHT
AS STRONG COLD AIR ADVECTION PUSHES THROUGH. WINDS AND SEAS BEGIN TO
DIMINISH LATE TONIGHT INTO WEDNESDAY MORNING.
THE RISK FOR LIGHT FREEZING SPRAY ACROSS THE COASTAL WATERS, MAINLY
THE NEARSHORE WATERS INTO WEDNESDAY.
OUTLOOK /WEDNESDAY NIGHT THROUGH SUNDAY/...
NEW YEARS DAY: MODERATE RISK FOR SMALL CRAFT ADVISORY WINDS
WITH LOCAL GUSTS UP TO 30 KT. AREAS OF ROUGH SEAS. FREEZING
SPRAY, CHANCE OF SNOW. AREAS OF VISIBILITY 1 NM OR LESS.
THURSDAY NIGHT: MODERATE RISK FOR SMALL CRAFT ADVISORY WINDS
WITH GUSTS UP TO 30 KT. SEAS UP TO 5 FT. CHANCE OF FREEZING
SPRAY.
FRIDAY: LOW RISK FOR SMALL CRAFT ADVISORY WINDS WITH GUSTS UP
TO 25 KT. SEAS UP TO 5 FT. CHANCE OF FREEZING SPRAY, SLIGHT
CHANCE OF SNOW.
FRIDAY NIGHT: LOW RISK FOR SMALL CRAFT ADVISORY WINDS WITH
GUSTS UP TO 25 KT. AREAS OF SEAS APPROACHING 5 FT.
SATURDAY: WINDS LESS THAN 25 KT. SEAS LOCALLY APPROACHING 5 FT.
SATURDAY NIGHT THROUGH SUNDAY: WINDS LESS THAN 25 KT.
BOX WATCHES/WARNINGS/ADVISORIES
CT...NONE.
MA...WIND ADVISORY UNTIL 1 AM EST WEDNESDAY FOR MAZ004>007-013>024-
026.
WINTER WEATHER ADVISORY FROM 7 PM WEDNESDAY TO 1 PM EST
THURSDAY FOR MAZ023-024.
RI...NONE.
MARINE...GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR ANZ230-236.
GALE WARNING UNTIL 7 AM EST WEDNESDAY FOR ANZ231>235-237-250-
251-254>256.
DISCUSSION...DOOLEY/HRENCECIN
AVIATION...MCMINN
MARINE...DOOLEY/HRENCECIN
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