412
FXUS61 KBOX 260715
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
315 AM EDT WED MAR 26 2025
SYNOPSIS
A FAST MOVING DISTURBANCE MAY TRIGGER A FEW BRIEF PASSING
RAIN/HIGH TERRAIN SNOW SHOWERS THURSDAY NIGHT. DRY AND PLEASANT
WEATHER FOLLOWS FOR FRIDAY. PERIODS OF UNSETTLED WEATHER ARE ON
TAP FRIDAY NIGHT THROUGH MONDAY WITH TEMPERATURES HIGHLY
UNCERTAIN DEPENDING ON THE LOCATION OF A BACKDOOR FRONT...BUT
LEANING TOWARDS TEMPS BEING ON THE CHILLY SIDE EXCEPT PERHAPS
FOR PARTS OF CONNECTICUT AND SOUTHWEST MASSACHUSETTS.
NEAR TERM /UNTIL 6 PM THIS EVENING/
KEY MESSAGES:
* RAIN MOVES THROUGH FAR SOUTHEASTERN MASSACHUSETTS, CAPE COD,
AND THE ISLANDS THIS MORNING.
* MID-LEVEL DISTURBANCE THIS AFTERNOON MAY BRING SCATTERED
SHOWERS, INCLUDING GRAUPEL OR SNOW OVER HIGHER ELEVATIONS.
A QUIET MORNING FOR MOST OF SOUTHERN NEW ENGLAND, BUT AREAS IN
FAR SOUTHEASTERN MASSACHUSETTS, CAPE COD, AND THE ISLANDS WILL
SEE PERIODS OF RAIN THROUGH MID TO LATE MORNING. A WEAK LOW-
PRESSURE SYSTEM DEVELOPED OFF THE MID-ATLANTIC COAST OVERNIGHT,
AND THE LATEST MODEL CONSENSUS HAS SHIFTED SLIGHTLY NORTH. AS A
RESULT, LOW- END POPS HAVE BEEN EXPANDED INTO SOUTHERN RHODE
ISLAND AND SOUTHEASTERN MASSACHUSETTS, THOUGH THE HIGHEST
CONFIDENCE IN MEASURABLE RAINFALL REMAINS SOUTH AND EAST OF THE
CAPE COD CANAL. 850MB TEMPERATURES RANGE FROM -2C TO -4C, WHILE
SURFACE TEMPERATURES ARE IN THE MID TO UPPER 30S. THIS SUPPORTS
PREDOMINANTLY RAIN, THOUGH A BRIEF RAIN/SNOW MIX CANNOT BE RULED
OUT IF THE PRECIPITATION EXTENDS FURTHER NORTHWEST INTO RHODE
ISLAND AND NORTHERN PLYMOUTH OR BRISTOL COUNTIES, WHERE SURFACE
TEMPERATURES ARE NEAR FREEZING. THE SYSTEM MOVES NORTHEAST, WITH
PRECIPITATION ENDING ACROSS THE OUTER CAPE AND NANTUCKET BY
LATE MORNING. COME THIS AFTERNOON, A MID-LEVEL SHORTWAVE AND
ASSOCIATED COLD POOL WILL MOVE INTO THE REGION, WITH 500MB
TEMPERATURES AROUND -34C. WELL MIXED BOUNDARY LAYER , WITH STEEP
LOW-LEVEL LAPSE RATES, WILL LIKELY SUPPORT CONVECTIVE/POP-UP
SHOWERS ACROSS SOUTHERN NEW ENGLAND. SOME OF THESE SHOWERS MAY
PRODUCE SNOW OVER THE HIGHER ELEVATIONS AND COULD CONTAIN
GRAUPEL. DESPITE THE DEEP MIXING, WINDS ALOFT ARE RELATIVELY
WEAK, LIMITING THE GUST POTENTIAL THIS AFTERNOON TO AROUND 20
MPH. HIGH TEMPERATURES WILL RANGE FROM THE 40S TO NEAR 50F ALONG
THE COASTAL PLAIN.
SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/
KEY MESSAGES:
* CLEARING SKIES TONIGHT WILL GIVE WAY TO A BREEZY AND
SEASONABLY COOL THURSDAY WITH MOSTLY SUNNY SKIES AND HIGHS IN
THE UPPER 40S TO LOW 50S.
TONIGHT: MID-LEVEL LOW EXITS TO THE EAST, WITH RISING HEIGHTS
AND INCREASING SURFACE PRESSURE TO THE SOUTHWEST. SKIES WILL
CLEAR, BUT A STEADY NORTHWEST FLOW WILL LIMIT RADIATIONAL
COOLING. EXPECTING A SEASONABLY COOL NIGHT, WITH LOWS IN THE 20S
INLAND AND AROUND 30F ALONG THE COAST. CITIES LIKE BOSTON MAY
STAY SLIGHTLY WARMER, WITH LOWS IN THE MID-30S.
THURSDAY: HIGH PRESSURE TO THE SOUTHWEST AND LOW PRESSURE OVER
THE MARITIMES WILL MAINTAIN NORTHWEST FLOW, MAKING FOR A BREEZY
DAY WITH GUSTS AROUND 20 MPH. WITH RISING 500MB HEIGHTS AND
DECREASING MOISTURE (PWATS BELOW 0.15"), SKIES WILL REMAIN
MOSTLY CLEAR. BUT WITH COOLER TEMPERATURES ALOFT, -7C AT 850MB,
WILL KEEP HIGHS IN THE UPPER 40S AND LOW 50S.
LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/
KEY MESSAGES:
* A FEW BRIEF RAIN/HIGH TERRAIN SNOW SHOWERS POSSIBLE THU NIGHT
* DRY & PLEASANT ON FRIDAY WITH HIGHS MAINLY IN THE 50S
* PERIODS OF UNSETTLED/WET WEATHER FRI NIGHT THROUGH MON WITH
BACKDOOR COLD IN THE VICINITY OF SNE WITH HIGHS 30S/40S NORTH
OF THE FRONT AND 60S/70S TO THE SOUTH OF THE BOUNDARY
* CURRENT INDICATIONS ARE THAT MUCH OF OUR REGION WILL BE ON
THE CHILLY SIDE THIS WEEKEND, BUT PARTS OF CT/SOUTHWEST MA MAY
WARM SECTOR SAT WHICH COULD ALLOW FOR A 30-40 DEGREE TEMP
SPREAD IN SNE
DETAILS...
THURSDAY NIGHT...
ANOTHER FAST MOVING MOISTURE STARVED SHORTWAVE WILL CROSS THE
REGION THU NIGHT. THERE MIGHT BE ENOUGH MOISTURE FOR A BRIEF
SPOT SHOWER/HIGH TERRAIN SNOW SHOWER...BUT GENERALLY DRY WEATHER
WILL PREVAIL.. LOWS SHOULD BE MAINLY IN THE UPPER 20S TO THE
MIDDLE 30S.
FRIDAY...
A BRIEF RIDGE OF HIGH PRESSURE BUILDS IN BEHIND THE SHORTWAVE
ON FRI. THIS WILL RESULT IN A DRY DAY WITH PLEASANT AFTERNOON
TEMPS. HIGHS SHOULD TOP OUT MAINLY IN THE 50S. SOME WNW WIND
GUSTS OF 20+ MPH ARE POSSIBLE.
FRIDAY NIGHT THROUGH MONDAY... '
A TRICKY FORECAST IN THIS PERIOD AS LOW PRESSURE ACROSS THE
CENTRAL PLAINS LIFTS NORTHEASTWARD TOWARDS THE GREAT LAKES. AT
THE SAME TIME...HIGH PRESSURE BUILDING ACROSS EASTERN CANADA
WILL ALLOW FOR A BACKDOOR COLD FRONT TO BE IN THE VICINITY OF
SOUTHERN NEW ENGLAND. THERE IS HIGH UNCERTAINTY AS TO WHERE THIS
FRONT SETS UP...BUT IT IS POSSIBLE IT MAY BISECT SOMEWHERE
ACROSS SOUTHERN NEW ENGLAND FOR A PERIOD OF TIME. HIGH TEMPS ARE
LIKELY TO ONLY BE IN THE 30S/40S NORTH OF THE FRONT AND 60S/70S
TO THE SOUTH OF THE BOUNDARY. FOR WHAT ITS WORTH...THE LATEST
GFS/ECMWF DRAPED ACROSS OUR SOUTHWEST ZONES. THIS WOULD RESULT
IN COOL TEMPS FOR MOST OF THE REGION...BUT PERHAPS PARTS OF
CT/SOUTHWEST MA MAY END UP SIGNIFICANTLY WARMER SAT DEPENDING ON
WHERE THE BOUNDARY SETS UP. IF THEY ARE ABLE TO WARM
SECTOR...WE MAY SEE A 30-40 DEGREE TEMP DIFFERENTIAL ACROSS THE
COUNTY WARNING AREA ON SAT!
IT ALSO LOOKS UNSETTLED AT TIMES FRI NIGHT THROUGH MON WITH A
FEW PERIODS OF WET WEATHER LIKELY. THIS WILL DEPEND ON THE
LOCATION OF THE BOUNDARY AND TIMING OF THE INDIVIDUAL WAVES OF
LOW PRESSURE RIDING ALONG IT. SO NOT EXPECTING THE ENTIRE TIME
FRAME TO BE A WASHOUT...BUT THERE SHOULD BE SOME PERIODS OF WET
WEATHER ESPECIALLY NORTH OF THE FRONTAL BOUNDARY. IN FACT...WE
CAN NOT RULE OUT THE LOW RISK FOR A BIT OF SNOW/ICE ACROSS THE
INTERIOR HIGH TERRAIN GIVEN STRONG HIGH PRESSURE IN EASTERN
CANADA. THAT BEING SAID...ODDS FAVOR MAINLY A LIQUID EVENT FOR
MOST OF OUR REGION.
TUESDAY...
QUITE A BIT OF UNCERTAINTY ON THE TIMING...BUT WE MAY BE
TRENDING DRIER BY TUE.
AVIATION /07Z WEDNESDAY THROUGH SUNDAY/
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
06Z TAF UPDATE...
TODAY...HIGH CONFIDENCE.
VFR WITH JUST A LOW RISK OF BRIEF MVFR CONDITIONS TOWARDS THE
CAPE/ISLANDS THIS MORNING AS A FEW SHOWERS MAY CROSS THIS REGION.
WE ALSO MAY SEE A FEW BRIEF SPOT SHOWERS/HIGH TERRAIN WET SNOW
FLAKES THIS AFTERNOON AND EVEN A BIT OF GRAUPEL...BUT THE VAST
MAJORITY OF THE DAY WILL BE DRY. W WINDS 5-15 KNOTS.
TONIGHT...HIGH CONFIDENCE.
VFR WITH JUST A FEW BRIEF SPOT SHOWERS PERHAPS LINGERING INTO
PART OF THE EVENING. WNW WINDS 5-10 KNOTS.
THURSDAY...HIGH CONFIDENCE.
VFR WITH WNW WINDS 8-15 KNOTS.
BOS TAF...HIGH CONFIDENCE. LOW RISK OF A BRIEF SEA BREEZE LATE
THIS MORNING INTO MID AFTERNOON...BUT NOT ENOUGH CONFIDENCE TO
INSERT INTO THE TAF.
BDL TAF...HIGH CONFIDENCE.
OUTLOOK /THURSDAY NIGHT THROUGH SUNDAY/...
THURSDAY NIGHT: MAINLY VFR, WITH LOCAL IFR POSSIBLE. BREEZY.
FRIDAY: VFR. BREEZY.
FRIDAY NIGHT: MAINLY MVFR, WITH LOCAL VFR POSSIBLE. BREEZY.
CHANCE SHRA.
SATURDAY: MAINLY MVFR, WITH LOCAL IFR POSSIBLE. BREEZY. CHANCE
SHRA.
SATURDAY NIGHT: MAINLY MVFR, WITH AREAS IFR POSSIBLE. BREEZY.
CHANCE SHRA, FZRA LIKELY.
SUNDAY: MAINLY MVFR, WITH AREAS IFR POSSIBLE. BREEZY. SHRA
LIKELY, FZRA LIKELY.
MARINE
FORECASTER CONFIDENCE LEVELS:
LOW - LESS THAN 30 PERCENT.
MEDIUM - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
TODAY THROUGH THURSDAY: HIGH CONFIDENCE.
WEAK LOW PRESSURE SYSTEM BRINGS A PERIOD OF LIGHT RAIN TO THE
SOUTHERN AND SOUTHEASTERN WATERS THIS MORNING. HIGH PRESSURE
NOSES NORTH LATE TONIGHT INTO THURSDAY LEADING TO DRYING
CONDITIONS AND CLEAR SKIES. SEAS THROUGHOUT THIS TIME REMAIN
BELOW ADVISORY CRITERIA. WEST TO SOUTHWEST WIND 10 TO 15 KNOTS
TODAY, LOW CHANCE OF A WEAK SEA BREEZE WHERE WIND SHIFTS TO THE
EAST (ONSHORE) FOR EASTERN COASTAL MASSACHUSETTS. TONIGHT, WIND
SHIFTS TO THE NORTHWEST THROUGH THURSDAY AT 15 TO 20 KNOTS.
OUTLOOK /THURSDAY NIGHT THROUGH SUNDAY/...
THURSDAY NIGHT: LOW RISK FOR SMALL CRAFT ADVISORY WINDS WITH
GUSTS UP TO 25 KT. SEAS LOCALLY APPROACHING 5 FT. SLIGHT CHANCE
OF RAIN SHOWERS.
FRIDAY: LOW RISK FOR SMALL CRAFT ADVISORY WINDS WITH GUSTS UP
TO 25 KT. AREAS OF SEAS APPROACHING 5 FT.
FRIDAY NIGHT: WINDS LESS THAN 25 KT. CHANCE OF RAIN SHOWERS.
SATURDAY: LOW RISK FOR SMALL CRAFT ADVISORY WINDS WITH GUSTS UP
TO 25 KT. SEAS LOCALLY APPROACHING 5 FT. CHANCE OF RAIN
SHOWERS.
SATURDAY NIGHT: WINDS LESS THAN 25 KT. LOCAL ROUGH SEAS. CHANCE
OF RAIN SHOWERS.
SUNDAY: LOW RISK FOR SMALL CRAFT ADVISORY WINDS WITH GUSTS UP
TO 20 KT. SEAS UP TO 5 FT. CHANCE OF RAIN SHOWERS.
BOX WATCHES/WARNINGS/ADVISORIES
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EDT EARLY THIS MORNING FOR
ANZ254>256.
SYNOPSIS...FRANK/DOOLEY
NEAR TERM...DOOLEY
SHORT TERM...DOOLEY
LONG TERM...FRANK
AVIATION...FRANK/DOOLEY
MARINE...FRANK/DOOLEY
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