FXUS61 KBOX 111157
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
757 AM EDT WED MAR 11 2026
WHAT HAS CHANGED
SMALL CRAFT ADVISORIES HOISTED ON MOST WATERS FOR THIS EVENING INTO
THURSDAY RIVER FLOOD WARNING IN EFFECT FOR THE TAUNTON RIVER AT
BRIDGEWATER DUE TO SNOWMELT-INDUCED RIVER RISE TO MINOR FLOOD STAGE
COLD FRONT MOVING IN THURS HAS SLOWED DOWN AND COULD ALLOW FOR HIT
OR MISS SHOWERS OR EVEN A RUMBLE OF THUNDER TONIGHT
&&
KEY MESSAGES
- BACKDOOR COLD FRONT BRINGS COOLER TEMPS AND NORTHEAST WINDS TO
NORTHERN/EASTERN MA TODAY
- MILD TONIGHT WITH HIT OR MISS SHOWERS, WITH THUNDER ALSO
POSSIBLE
- COLD FRONT MOVES THRU THURS, BRINGING RAIN AND FALLING TEMPS
THROUGH THE DAY EVEN A RISK FOR MINOR SNOW ACCUMULATION IN
INTERIOR SOUTHERN NEW ENGLAND THURS DEPENDING ON THE TIMING
- MINOR SNOW ACCUMULATIONS POSSIBLE LATE FRI-FRI NIGHT OVER THE
HIGHER ELEVATIONS
- POTENTIAL FOR WIDESPREAD SHOWERS WITH LOCALLY HEAVY RAINFALL
SUNDAY NIGHT INTO MONDAY WHICH MAY LEAD TO MINOR RIVER
FLOODING
&&
DISCUSSION
KEY MESSAGE 1BACKDOOR COLD FRONT BRINGS COOLER TEMPS AND
NORTHEAST WINDS TO NORTHERN/EASTERN MA TODAY
A BACKDOOR COOL FRONT IS TAKING SHAPE EARLY THIS MORNING IN NORTHERN
ME AND IS EXPECTED TO BUILD SOUTHWARD THRU ME/NH THRU EARLY
OVERNIGHT AND INTO EASTERN AND CENTRAL MA BY THE EARLY MORNING HOURS
AND THEN EVENTUALLY STALLING INTO CT/RI BY LATE IN THE MORNING
NORTH OF THE BOUNDARY, EXPECT AN OVERCAST AND RAW DAY WITH NE WINDS
AND TEMPS EITHER HOVERING OR SLOWLY FALLING FOR A TIME (SOME AREAS
TODAY IN NORTHERN MA MAY STRUGGLE TO GET OUT OF THE MID 40S), WITH
WARMER TEMPS SOUTH AND WEST OF THE FRONTAL BOUNDARY (HIGHS IN THE
LOWER 60S FOR CT AND SOUTHERN RI) OTHER THAN HIT OR MISS SHOWERS ON
THE COOL SIDE OF THE FRONTAL BOUNDARY, MOST OF THE DAYTIME PERIOD
SHOULD BE LARGELY DRY IN RESPONSE TO STRONG SOUTHERLY FLOW AND WARM
ADVECTION, THIS BOUNDARY RETURNS BACK NORTHWARD AS A WARM FRONT
DURING THE AFTERNOON TO EARLY EVENING, WHICH THEN BRINGS WITH IT A
SURGE IN TEMPS AND DEWPOINTS SO FOR AREAS IN NORTHERN AND NORTHEAST
MA ON THE NORTH SIDE OF THE FRONTAL BOUNDARY, CALENDAR-DAY HIGHS ARE
MORE LIKELY TO BE MET AFTER SUNDOWN
KEY MESSAGE 2MILD TONIGHT WITH HIT OR MISS SHOWERS, WITH
THUNDER ALSO POSSIBLE
AHEAD OF A POWERFUL BUT SLOWING COLD FRONT, A STRONG BURST OF
WARM/MOIST ADVECTION TAKES PLACE TONIGHT ON 850 MB WINDS AROUND 45-
55 KT THIS BRINGS RISING DEWPOINTS (IN THE 50S) AND PWAT VALUES OF
UP TO 15 INCHES, AS WELL AS DECREASING THE STATIC-STABILITY ABOVE
THE STRONG FRONTAL INVERSION MOST MODELS SHOW SHOWALTER INDICES
DROPPING BELOW 0 INDICATIVE OF ELEVATED INSTABILITYBUT THE DEGREE
TO WHICH THEY DO AND WHAT MAY FORCE ANY SHOWER ACTIVITY IS IN SOME
QUESTION SIMILAR TO YESTERDAY THE 00Z NAM SHOWS A VERY-PROBABLY-
OVERDONE LOOK WITH LAPSE RATES ABOVE 700 MB AROUND 7 C/KM, WHICH
GENERATES AN EXORBITANT AMOUNT OF MUCAPE AROUND 1500 J/KG RAP AND
GFS MUCAPES SEEM MORE REALISTIC AT AROUND 200-400 J/KG THIS COULD
BE ENOUGH TO PRODUCE SOME THUNDER AND HAVE INCLUDED A MENTION OF
THUNDER IN WITH THE CHANCE-LEVEL POP DURING THE EVENING IT
ALSO LOOKS LIKE THE FORCING IS SLOWER TO ARRIVE, WHICH LENDS
ITSELF TO QUESTIONS ON WHAT MAY GET ANY SHOWERS GOING AND IT
COULD BE FROM REMNANT CONVECTIVE ACTIVITY IN THE MID-ATLANTIC
GIVEN MORE ACTIVE THUNDERSTORMS ANTICIPATED THERE TODAY, AS
OFFERED BY SOME HIGH- RES SOLUTIONS WITH THE FRONT NOW SLOWER
TO LURCH INTO THE BERKSHIRES, LOW TEMPS LOOK TO STAY IN THE LOW
TO MID 50S IN MOST AREAS GIVEN THE SOUTHERLY WINDS AND OVERCAST
KEY MESSAGE 3COLD FRONT MOVES THRU THURS, BRINGING RAIN AND
FALLING TEMPS THROUGH THE DAY EVEN A RISK FOR MINOR SNOW
ACCUMULATION IN INTERIOR SOUTHERN NEW ENGLAND THURS DEPENDING
ON THE TIMING
COLD FRONT THEN MOVES INTO SNE THURS, WHICH IS WHEN THE BEST CHANCE
FOR WIDESPREAD PRECIPITATION SETS IN MUCH OF THIS WILL INITIALLY
FALL AS RAIN, BUT STRONG SHALLOW COLD ADVECTION SHOULD ALLOW FOR
FALLING TEMPS THROUGH THE DAY ONE THING TO WATCH IS THE POTENTIAL
FOR ANAFRONTALLY-FORCED PRECIPITATION THURS AFTN AS SECONDARY
SHORTWAVE TROUGH IN THE CENTRAL APPALACHIANS DRAWS MOISTURE
NORTHWARD FROM THE MID-ATLANTIC ON THE COLD SIDE OF THE FRONTAL
BOUNDARY, INTO AN AIRMASS WHICH WOULD BE COLD ENOUGH FOR A MINOR
ACCUMULATION OF WET SNOW IF THAT WERE TO HAPPEN, MINOR ACCUMULATING
SNOW COULD DEVELOP WITH BETTER CHANCE IN INTERIOR SOUTHERN NEW
ENGLAND WHILE SNOW IN MARCH IS NOT UNCOMMMON, CONSIDERING THE MID
TO UPPER 70S SOME AREAS SAW ON TUESDAY IT WOULD BE QUITE A WHIPLASH
MILD TEMPS FROM THE OVERNIGHT (MID 50S) SHOULD SERVE AS THURS'S
HIGHS, WITH HOURLY TEMPS THEN FALLING STEADILY THROUGH THE DAY
KEY MESSAGE 4MINOR SNOW ACCUMULATIONS POSSIBLE LATE FRI-FRI NIGHT
OVER THE HIGHER ELEVATIONS
ANOTHER ROBUST NORTHERN STREAM SHORTWAVE MOVES ACROSS NEW ENG FRI
NIGHT BEFORE LIFTING TO THE NORTH SAT MODEST LOW LEVEL JET DEVELOPS
AHEAD OF THE SHORTWAVE WHICH WILL BRING INCREASING MOISTURE INTO SNE
WHILE ALSO ENHANCING FORCING FOR ASCENT FROM WARM ADVECTION A
PERIOD OF RAIN AND SNOW SHOWERS ARE LIKELY SOMETIME FRI AFTERNOON
INTO FRI NIGHT SNOW SHOWERS WILL BE FAVORED OVER THE WORCESTER
HILLS AND BERKSHIRES WHERE UP TO AN INCH ACCUM IS POSSIBLE MAINLY
RAIN SHOWERS IN THE COASTAL PLAIN SYSTEM LIFTS TO THE NORTH BY SAT
WITH CLIPPER LOW TRACKING TO THE NORTH AND PUSHING A COLD FRONT
THROUGH BY SAT MORNING LEADING TO A DRY AND SEASONABLE SAT BUT WITH
BLUSTERY W WINDS
KEY MESSAGE 5POTENTIAL FOR WIDESPREAD SHOWERS WITH LOCALLY HEAVY
RAINFALL SUNDAY NIGHT INTO MONDAY WHICH MAY LEAD TO MINOR RIVER
FLOODING
MORE AMPLIFIED UPPER TROUGH APPROACHES FROM THE WEST MONDAY AS
STRONG COLD FRONT MOVES INTO THE REGION ROBUST PRE-FRONTAL LOW
LEVEL JET DEVELOPS WITH ANOMALOUS PWATS ADVECTING NORTHWARD INTO THE
REGION WIND AND PWAT ANOMALIES ALONG WITH ELEVATED INSTABILITY
SUGGEST POTENTIAL FOR LOCALLY HEAVY RAINFALL WITH CONVECTIVE SHOWERS
AND POSSIBLE A FEW T-STORMS, CENTERED AROUND THE SUNDAY NIGHT INTO
MONDAY PERIOD PROBS FOR 1"+ OF RAIN ARE 30-50 PERCENT BUT THIS IS A
DECENT SIGNAL AT THIS RANGE THE 90TH PERCENTILE WHICH REPRESENTS A
REASONABLE WORST CASE SCENARIO INDICATES 1-2 INCHES RAINFALL WHICH
COULD LEAD TO SOME RIVER FLOODING CONCERNS GIVEN THE RISING WATER
LEVELS FROM SNOWMELT MMEFS ENSEMBLE GUIDANCE FROM THE NAEFS SHOW 40-
60 PERCENT PROBS FOR MINOR FLOODING EARLY NEXT WEEK ALONG THE
PAWTUXET, PAWCATUCK, AND WOOD RIVERS IN RI AND THE TAUNTON RIVER AT
BRIDGEWATER LOW PROBS (20-30%) FOR MINOR FLOODING NOTED ALONG THE
LOWER REACHES OF THE MAINSTEM CONNECTICUT RIVER FROM HARTFORD
THROUGH MIDDLE HADDAM
STILL TOO EARLY TO KNOW HOW MUCH WIND WE'LL HAVE WITH THE LLJ AS
THIS WILL DEPEND ON HOW MILD IT GETS, BUT EXPECT A PERIOD OF GUSTY S
WINDS AFTER A COOL DAY SUNDAY, RISING TEMPS LIKELY SUN NIGHT AND A
MILD DAY MONDAY
COLD FRONT MOVES THROUGH BY MON EVENING WITH ANOTHER SURGE OF
MODIFIED ARCTIC AIR ON TUE RESULTING IN TEMPS WELL BELOW NORMAL
&&
AVIATION /12Z WEDNESDAY THROUGH SUNDAY/
FORECASTER CONFIDENCE LEVELS
LOW - LESS THAN 30 PERCENT
MODERATE - 30 TO 60 PERCENT
HIGH - GREATER THAN 60 PERCENT
12Z TAF UPDATE:
MODERATE CONFIDENCE
PRIMARILY VFR ACROSS THE AREA CURRENTLY, BUT THAT IS EXPECTED TO
CHANGE AS WE GO THROUGH THE MORNING INTO AFTERNOON LOW CLOUDS
AND BR ARE EXPECTED TO DEVELOP ESPECIALLY ACROSS THE EASTERN
HALF OF SOUTHERN NEW ENGLAND WE HAVE A WEAK "BACK DOOR" FRONT
DRAPED ACROSS THE AREA, WITH NE SURFACE WINDS NORTH OF THAT
FRONT, AND LIGHT S WINDS SOUTH OF THE FRONT SATELLITE SHOWS AN
AREA OF LOW CLOUDS ABOUT 50 MILES EAST OF BOS HEADED WESTWARD,
SO THINKING THIS IS A SIGNAL THAT FOR IFR CEILINGS TO OCCUR BY
SOMETIME EARLY THIS AFTERNOON TIMING IS DIFFICULT, SO GENERALLY
STAYED CLOSE TO PROJECTIONS IN THE 06Z TAFS HOW FAR WEST THE
IFR CONDITIONS ARE ABLE TO PUSH THIS EVENING IS ALSO IN
QUESTION BEST GUESS AT THIS POINT IS NOT MUCH FURTHER WEST THAN
AN ORH-IJD LINE, WITH SOME MVFR INTO THE CT RIVER VALLEY
THAT FRONT WILL START LIFTING NORTHWARD OVERNIGHT, RESULTING IN
SURFACE WINDS TRANSITIONING TO S/SW DIRECTION, AND GUSTING OVER
20KT IN SOME AREAS HOWEVER MVFR/IFR CONDITIONS WILL CONTINUE
EXPECT SCATTERED SHRA AND PERHAPS AND ISOLATED TSRA TO MOVE
ACROSS THE REGION OVERNIGHT AGAIN, CONFIDENCE IS MODERATE AT
BEST WITH REGARD TO TIMING AT ANY LOCATION PROBABILITY OF TSRA
AT THIS POINT IS 15-25% DURING THE 02-06Z TIMEFRAME, SO HAVE
LEFT EXPLICIT MENTION OF TS OUT OF THE TAFS AT THIS POINT
LASTLY, STRONG WINDS JUST ABOVE THE SURFACE (1000-3000FT AGL)
ARE EXPECTED TO INCREASE TO 45-55KT LATE THIS AFTERNOON THROUGH
A GOOD PART OF THE OVERNIGHT HOURS THUS HAVE MAINTAINED MENTION
OF LLWS
AS WE GET INTO THURSDAY MORNING, A FRONT WILL SWING THROUGH THE
REGION, AND VFR CONDITIONS ARE EXPECTED TO DEVELOP AFTER THE
FRONT ALONG WITH SURFACE WINDS TURNING MORE W, WITH GUSTS OVER
20KT AT TIMES
KBOS TERMINALMODERATE CONFIDENCE IN TAF IFR CEILINGS ARE
EXPECTED TO DEVELOP, BUT TIMING IS IN QUESTION 18Z IS CURRENT
BEST GUESS, BUT IT COULD BE ANYWHERE IN THE 16Z-21Z TIMEFRAME
SMALL PROBABILITY FOR BRIEF TS IN THE 02-07Z PERIOD, BUT NOT
ENOUGH CONFIDENCE TO ADD TO TAF
KBDL TERMINALMODERATE CONFIDENCE IN TAF EXPECT MVFR
CONDITIONS TO DEVELOP BY 01Z, BUT IT COULD BE EARLIER
UNCERTAINTY IN THE SPECIFIC TIMING OF SHRA AND PERHAPS A BRIEF
TSRA LATE TODAY/THIS EVENING CONFIDENCE OF TS IS TOO LOW TO
INCLUDE IN TAF AT THIS POINT, BUT COULD OCCUR BETWEEN 00-05Z
TIME
OUTLOOK /THURSDAY THROUGH SUNDAY/
THURSDAY: MAINLY VFR, WITH LOCAL MVFR POSSIBLE WINDY WITH
AREAS OF GUSTS UP TO 30 KT RA LIKELY, CHANCE SN
THURSDAY NIGHT: VFR BREEZY
FRIDAY: VFR BREEZY SLIGHT CHANCE RA
FRIDAY NIGHT: WINDY WITH AREAS OF GUSTS UP TO 30 KT CHANCE RA,
CHANCE SN
SATURDAY: WINDY WITH AREAS OF GUSTS UP TO 30 KT
SATURDAY NIGHT: BREEZY
SUNDAY: BREEZY SLIGHT CHANCE RA
&&
MARINE
FORECASTER CONFIDENCE LEVELS
LOW - LESS THAN 30 PERCENT
MODERATE - 30 TO 60 PERCENT
HIGH - GREATER THAN 60 PERCENT
A BACKDOOR COLD FRONT WILL BE WORKING SOUTHWARD FROM THE
COASTAL ME WATERS WHICH WILL BRING AN INCREASED NE WIND TO THE
WATERS TODAY AT AROUND 10-15 KT WHICH THEN BECOMES ESE/SE LATE
IN THE DAY ELSEWHERE WINDS MAINLY SOUTHERLY TODAY AROUND 10-15
KT, INCREASING TO AROUND 20 KT SOUTHERN WATERS LATE
SCAS HOISTED ON MOST WATERS STARTING EARLY THIS EVENING AND
THROUGH MIDAFTERNOON THURS AS SOUTHERLY WINDS INCREASE TO AROUND
25-30 KT IN GUSTS SEAS WILL ALSO BE BUILDING TO 5-10 FT THRU
THURS WINDS WILL EVENTUALLY SHIFT TO NW LATE THURS AFTERNOON
TO SCA CRITERION
OUTLOOK /THURSDAY THROUGH SUNDAY/
THURSDAY: MODERATE RISK FOR SMALL CRAFT ADVISORY WINDS WITH
LOCAL GUSTS UP TO 30 KT AREAS OF ROUGH SEAS RAIN LIKELY
THURSDAY NIGHT: LOW RISK FOR SMALL CRAFT ADVISORY WINDS WITH
GUSTS UP TO 25 KT LOCAL ROUGH SEAS
FRIDAY: LOW RISK FOR SMALL CRAFT ADVISORY WINDS WITH GUSTS UP
TO 25 KT AREAS OF SEAS APPROACHING 5 FT
FRIDAY NIGHT: STRONG WINDS WITH GUSTS UP TO 35 KT AREAS OF
ROUGH SEAS CHANCE OF RAIN
SATURDAY: STRONG WINDS WITH GUSTS UP TO 35 KT ROUGH SEAS UP TO
11 FT
SATURDAY NIGHT: WINDS LESS THAN 25 KT LOCAL ROUGH SEAS
SUNDAY: WINDS LESS THAN 25 KT SEAS LOCALLY APPROACHING 5 FT
&&
BOX WATCHES/WARNINGS/ADVISORIES
CTNONE
MANONE
RINONE
MARINESMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 2 PM EDT
THURSDAY FOR ANZ232>235-237-250-254>256
&&
DISCUSSIONKJC/LOCONTO
AVIATIONKJC/NASH
MARINEKJC/LOCONTO
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