864
FXUS61 KBOX 042331
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
631 PM EST SUN JAN 4 2026
WHAT HAS CHANGED
SNOWFALL AMOUNTS WERE INCREASED SLIGHTLY FOR LATE MONDAY INTO MONDAY
NIGHT. CONFIDENCE HAS INCREASED IN LIGHT ICING ACROSS THE INTERIOR
TUESDAY NIGHT.
KEY MESSAGES
- CLEARING AND COLD TONIGHT
- LIGHT SNOW ACCUMULATIONS, A COATING TO 2 INCHES, EXPECTED MON
AFTERNOON INTO MONDAY NIGHT
- CHANCES INCREASING FOR MIXED PRECIPITATION EVENT TUESDAY NIGHT
INTO WEDNESDAY.
- A BRIEF PERIOD OF DRY WEATHER ON THURSDAY FOLLOWED BY ANOTHER
ROUND OF UNSETTLED WEATHER INTO THE WEEKEND.
DISCUSSION
KEY MESSAGE 1...CLEARING AND COLD TONIGHT
RISING HEIGHTS TONIGHT AS MID LEVEL TROUGH CONTINUES TO MOVE EAST
AND HIGH PRES WILL BE BUILDING IN FROM THE WEST. NW WINDS MAY BECOME
BRIEFLY GUSTY THIS EVENING THEN DIMINISHING OVERNIGHT AS GRADIENT
SLACKENS WITH APPROACH OF HIGH PRES. WITH CLEARING SKIES EXPECT GOOD
RADIATIONAL COOLING OVERNIGHT AS WINDS BECOME LIGHT. LOWS SHOULD
DROP INTO THE SINGLE NUMBERS INTERIOR MA, WITH TEENS ELSEWHERE.
KEY MESSAGE 2...LIGHT SNOW ACCUMULATIONS MON AFTERNOON INTO MON NIGHT
A MODEST MID LEVEL SHORTWAVE WILL BE QUICKLY MOVING INTO THE REGION
MON AFTERNOON AND EVENING. AHEAD OF THE SHORTWAVE A WARM FRONT WILL
APPROACH FROM THE SW WITH MODEST OVERRUNNING DEVELOPING. SYNOPTIC
SCALE FORCING IS NOT OVERLY IMPRESSIVE BUT THE COLUMN DOES SATURATE
THROUGH THE SNOW GROWTH REGION AND LOW LEVELS ARE QUITE COLD WHICH
WILL HELP TO ENHANCE ISENTROPIC LIFT. THIS SHOULD RESULT IN A PERIOD
OF WIDESPREAD LIGHT SNOW, STARTING 1-3 PM IN THE WEST AND 3-6 PM IN
EASTERN NEW ENG. TEMPS WILL BE IN THE 20S WHEN SNOW BEGINS SO IT
WILL STICK IMMEDIATELY WHICH WILL HAVE SOME IMPACT TO THE EVENING
COMMUTE, ESPECIALLY IN THE WEST WHERE THE SNOW BEGINS EARLIER. BUT
SNOWFALL RATES WILL BE MORE THAN MANAGEABLE AT 0.5 INCH OR LESS PER
HOUR.
IT'S A FAIRLY QUICK MOVING SYSTEM SO SNOW SHOULD BE TAPERING OFF
BEFORE MIDNIGHT AS DRIER MOVES IN. THE SNOW GROWTH REGION DRIES OUT
QUICKLY WHICH COULD LEAD TO SNOW ENDING AS A PERIOD OF FREEZING
DRIZZLE. QPF AMOUNTS ARE LIGHT, GENERALLY UNDER 0.2", AND EXPECTED
SLR WILL BE 12-15:1. PROBABLY NOT MUCH MORE THAN THAT AS SNOW GROWTH
OMEGA IS NOT THAT STRONG. LOOKING AT ACCUMS OF 1-2 INCHES FOR MUCH
OF THE REGION, EXCEPT A COATING TO AN INCH CLOSER TO THE SOUTH
COAST. PTYPE ALL SNOW, BUT MAY MIX WITH OR CHANGE TO RAIN ON THE
ISLANDS MON EVENING AS BL WARMS WITH LIGHT S FLOW.
KEY MESSAGE 3...CHANCES INCREASING FOR MIXED PRECIPITATION
EVENT TUESDAY NIGHT INTO WEDNESDAY.
A GOOD PORTION OF TUESDAY LOOKS TO REMAIN DRY ONCE THE SNOW SHOWERS
MOVE OUT IN THE EARLY TO MID-MORNING. HOWEVER, ANOTHER SHORT WAVE
AND LOW PRESSURE SYSTEM LOOK TO MOVE INTO SOUTHERN NEW ENGLAND BY
TUESDAY NIGHT, BRINGING CHANCES FOR A MIXED PRECIP EVENT. EXCLUDING
THE NAM, THE REST OF THE MODELS ARE INDICATING A WARM NOSE OF AIR
WITH 850MB TEMPERATURES RANGING +2C TO +5C. GUIDANCE IS BEGINNING TO
HONE IN ON THE HIGHER TERRAIN AREAS OF THE BERKSHIRES AND WORCESTER
HILLS HAVING A HIGHER LIKELIHOOD OF SURFACE TEMPERATURES REMAINING
AT OR BELOW FREEZING, LEADING TO HIGHER CHANCES OF SEEING FREEZING
RAIN. STARTING TO SEE THE LATEST ROUND OF GUIDANCE CREEP UP IN THE
ICE ACCUMULATION, BRINGING CONSENSUS TO ABOVE 0.01" BUT BELOW 0.1"
IN THE HIGHER ELEVATIONS. SOUNDINGS CONTINUE TO FAVOR THIS PERIOD OF
FREEZING RAIN BEFORE SWITCHING TO ALL RAIN AS SURFACE TEMPERATURES
INCREASE HEADING INTO THE MID-MORNING HOURS ON WEDNESDAY.
KEY MESSAGE 4...A BRIEF PERIOD OF DRY WEATHER ON THURSDAY
FOLLOWED BY ANOTHER ROUND OF UNSETTLED WEATHER INTO THE WEEKEND.
THE TUESDAY/WEDNESDAY SYSTEM SHOULD MAKE ITS EXIT BY WEDNESDAY
NIGHT, AND A MID-LEVEL RIDGE WITH A SURFACE HIGH MOVES IN TO BRING A
PERIOD OF DRY WEATHER ON THURSDAY. UNFORTUNATELY, NOT EXPECTING THE
DRYNESS TO LAST AS ANOTHER SYSTEM IS PROJECTED TO PUSH INTO SOUTHERN
NEW ENGLAND AT SOME POINT ON FRIDAY. TEMPERATURES FRIDAY AND
SATURDAY REMAIN ABOVE FREEZING, WITH ENSEMBLE GUIDANCE INDICATING
SURFACE HIGH TEMPERATURES 10-15F ABOVE NORMAL, LEADING TO PRECIP
REMAINING SOLELY AS RAIN. GIVEN THIS IS STILL QUITE A WHILE OUT,
UNCERTAINTY REGARDING TIMING, PLACEMENT, AND PRECIP TOTALS REMAINS
HIGH.
AVIATION /00Z MONDAY THROUGH FRIDAY/
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH -GREATER THAN 60 PERCENT.
00Z TAF UPDATE...
NO MAJOR CHANGES. TRENDS REMAIN ON TRACK.
TONIGHT...HIGH CONFIDENCE.
VFR-MVFR CIGS TRENDING ALL VFR TONIGHT AS CLOUD COVER
DECREASES. NW WIND 5-15 KT BECOMING LIGHT TOWARD 12Z, EXCEPT
TOWARDS THE CAPE AND ISLANDS WHERE WINDS MAY CONTINUE LONGER AND
OCCASIONALLY GUST TO 20 KT.
MONDAY...HIGH CONFIDENCE.
VFR TO START, THEN LOWERING TO MVFR AFTER 19Z ACROSS CENTRAL/W
MA AND CT AS LIGHT SNOW OVERSPREADS THE REGION. SNOW MAY REACH
EASTERN MA/RI AFTER 21Z.
MONDAY NIGHT...MODERATE CONFIDENCE.
MVFR WITH AREAS OF IFR IN SNOW IN THE EVENING. MINOR ACCUMS
POSSIBLE. SNOW ENDING AROUND MIDNIGHT.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK /TUESDAY THROUGH FRIDAY/...
TUESDAY: MAINLY VFR, WITH LOCAL IFR POSSIBLE. SLIGHT CHANCE RA,
SLIGHT CHANCE FZRA.
TUESDAY NIGHT: MVFR/IFR CONDITIONS POSSIBLE. RA LIKELY, FZRA
LIKELY.
WEDNESDAY: MAINLY VFR, WITH LOCAL IFR POSSIBLE. CHANCE RA.
WEDNESDAY NIGHT THROUGH THURSDAY: VFR.
THURSDAY NIGHT: VFR. SLIGHT CHANCE RA.
FRIDAY: MAINLY VFR, WITH LOCAL MVFR POSSIBLE. BREEZY. CHANCE
RA.
MARINE
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
THROUGH MONDAY NIGHT...HIGH CONFIDENCE.
A PERIOD OF NW GUSTS TO 25 KT SHOULD DEVELOP THIS EVENING,
ESPECIALLY OVER THE EASTERN WATERS. SCA WAS ISSUED FOR EASTERN MA
WATERS AND OUTER SOUTHERN WATERS. WINDS DIMINISH LATE TONIGHT
THROUGH TUE WHILE SHIFTING TO SW LATE TUE AND TUE NIGHT. LOWERING
VSBYS LATE MON INTO MON NIGHT IN SNOW, CHANGING TO RAIN OVER
SOUTHERN WATERS.
OUTLOOK /TUESDAY THROUGH FRIDAY/...
TUESDAY: WINDS LESS THAN 25 KT. SLIGHT CHANCE OF RAIN, SLIGHT
CHANCE OF FREEZING RAIN.
TUESDAY NIGHT: WINDS LESS THAN 25 KT. CHANCE OF RAIN.
WEDNESDAY: WINDS LESS THAN 25 KT. SEAS LOCALLY APPROACHING
5 FT. CHANCE OF RAIN.
WEDNESDAY NIGHT THROUGH THURSDAY: WINDS LESS THAN 25 KT. AREAS
OF SEAS APPROACHING 5 FT.
THURSDAY NIGHT: WINDS LESS THAN 25 KT. SLIGHT CHANCE OF RAIN.
FRIDAY: WINDS LESS THAN 25 KT. CHANCE OF RAIN.
BOX WATCHES/WARNINGS/ADVISORIES
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 AM EST MONDAY FOR ANZ231-232-251-
255-256.
SMALL CRAFT ADVISORY UNTIL 5 AM EST MONDAY FOR ANZ250-254.
DISCUSSION...KJC/MCMINN
AVIATION...KJC/HRENCECIN
MARINE...KJC/MCMINN
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