613
FXUS61 KBOX 251146
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
746 AM EDT SAT APR 25 2026
WHAT HAS CHANGED
INCREASES TO RAIN CHANCES AND NORTHEAST WIND SPEEDS AND GUSTS
FOR SUNDAY INTO MONDAY FOR SOUTHEAST NEW ENGLAND. WHILE THESE
CHANGES WERE MINOR, MORE SIGNIFICANT INCREASES COULD BE NEEDED
PENDING THE TRACK OF COASTAL LOW PRESSURE TO SOUTHERN NEW
ENGLAND.
KEY MESSAGES
- INCREASING CLOUDINESS TODAY AND GENERALLY DRY WITH COOLING
ONSHORE BREEZES, ALTHOUGH LIGHT RAIN SHOWERS DEVELOP LATE
TODAY AND TONIGHT IN WESTERN MA INTO PORTIONS OF CT AND
SOUTHERN RI.
- COASTAL LOW PRESSURE JUST TO OUR SOUTH BRINGS CLOUDY AND COOL
WEATHER, NORTHEAST BREEZES AND PERIODS OF RAIN SHOWERS TO
SOUTHEAST NEW ENGLAND SUNDAY, POSSIBLY INTO MONDAY.
- DRY WEATHER WITH ONSHORE BREEZES RESUME EARLY TO MIDDLE OF
NEXT WEEK WITH A WARMING TREND TO TEMPS, BEFORE WEATHER TURNS
MORE UNSETTLED LATE IN THE WEEK.
DISCUSSION
KEY MESSAGE 1...INCREASING CLOUDINESS TODAY WITH COOLING ONSHORE
BREEZES, ALTHOUGH LIGHT RAIN SHOWERS DEVELOP LATE TODAY AND
ESPECIALLY TONIGHT FOR WESTERN MA AND PORTIONS OF CT AND
SOUTHERN RI.
SFC RIDGE IN PLACE ACROSS MOST OF SOUTHERN NEW ENGLAND WILL
SUPPLY ANOTHER ROUND OF MODEST ONSHORE FLOW/SEABREEZES TODAY,
WITH COOL TEMPERATURES IN PART FROM A UPPER-LEVEL LOW PARKED
OVER THE CANADIAN MARITIMES. TO OUR WEST IS A STREAM OF MID TO
HIGH LEVEL MOISTURE ACROSS WESTERN NY, WHICH WILL BE ADVANCING
ACROSS OUR AREA THROUGH TODAY. EXPECT INCREASING CLOUDINESS
TOWARD AN OVERCAST LOOK BY THIS AFTERNOON, ALTHOUGH FOR THE VAST
MAJORITY OF SOUTHERN NEW ENGLAND, THAT "OVERCAST" IS REALLY A
PRETTY EXTENSIVE CANOPY OF MID TO HIGH CLOUD COVER. WITH MID TO
HIGH CLOUDS AND ONSHORE FLOW, I KEPT HIGHS ON THE COOLER END OF
GUIDANCE IN THE MID/UPPER 40S FOR EASTERN MA AND THE SOUTH
COAST, AND LOWER TO MID 50S FURTHER INTO THE INTERIOR.
ALTHOUGH MUCH OF THE AREA IS DRY TODAY/TONIGHT, THE EXCEPTION IS
IN FAR WESTERN MA AND ADJACENT HARTFORD COUNTY IN CT, AND
EVENTUALLY INTO TOLLAND COUNTY RI AND SOUTHERN RI LATE TONIGHT.
SHOWERS ASSOCIATED WITH AN INITIALLY WEAK MID-LEVEL SHORTWAVE
TROUGH OVER MI END UP SHIFTING ESE TODAY, AND SOME OF THOSE
SHOWERS SHOULD BE ABLE TO MAKE IT INTO WESTERN MA/HARTFORD
COUNTY AREA LATE IN THE DAY (SHORTLY BEFORE SUNDOWN), THEN
EXPAND ESE TOWARD SOUTHERN RI TONIGHT. THE EASTERN AND NORTHERN
EXTENT OF THESE SHOWERS SHOULD BE STUNTED BY NORTHWESTERLY
CONFLUENT MID-LEVEL FLOW AND THE DRIER AIR IN PLACE; MOST BUFKIT
PROFILES SHOW A PRETTY ROBUST PLUME OF DRY AIR BELOW 850 MB IN
CENTRAL/EASTERN MA AND NORTHERN RI. THE NAM STILL REMAINS A MORE
BULLISH OUTLIER ON QPF, AND EVEN THOUGH THE GFS DID TICK UPWARD
SOME, SOME OF THAT QPF WILL BE LOST TO SATURATE THE PROFILE.
OFFERING PERIODS OF LIGHT RAIN FROM ABOUT WESTFIELD TO
WILLIMANTIC SOUTH AND WEST THRU MIDNIGHT, THEN EXPANDING
SOUTHEAST TOWARDS SOUTHERN RI/NEWPORT AREA OVERNIGHT. POSSIBLE
THAT SOME OF THAT COULD MIX WITH WET SNOWFLAKES IN THE TERRAIN
IN TOLLAND COUNTY BUT REALLY NOT OF MUCH IMPACT. HIGH RES
GUIDANCE ALSO SHOWS A RATHER SHARP PRECIP CUTOFF, FAR MORE SO
THAN THE COARSER-RES GLOBAL MODELS SHOW AND THAT PROBABLY IS
WHAT TRANSPIRES. THIS THEN SETS US UP FOR A LOWER-CONFIDENCE
FORECAST AS WE HEAD INTO SUNDAY AND MONDAY, TO BE ADDRESSED IN
THE NEXT KEY MESSAGE.
KEY MESSAGE 2...COASTAL LOW PRESSURE JUST TO OUR SOUTH BRINGS
CLOUDY AND COOL WEATHER, NORTHEAST BREEZES AND PERIODS OF RAIN
SHOWERS TO SOUTHEAST NEW ENGLAND SUNDAY, POSSIBLY INTO MONDAY.
LOW PRESSURE SOUTH OF LONG ISLAND SUNDAY MORNING, ON THE
SOUTHERN PERIPHERY OF THE HIGH PRESSURE IN PLACE OVER NEW
ENGLAND, SHOULD STILL FAVOR AT LEAST OVERCAST WITH BEST CHANCE
FOR RAIN ALONG THE SOUTH COAST, CAPE AND ISLANDS, TO GO ALONG
WITH ENHANCED NE WINDS. DEVIL'S IN THE DETAILS AND THE MAIN
ISSUE IS HOW FAR NORTH AND HOW QUICKLY WILL THIS LOW PRESSURE
GET TO AT LEAST SOUTHEAST NEW ENGLAND FOR SUNDAY AND POSSIBLY
INTO MONDAY. SEEMINGLY KEY IN THAT EVOLUTION IS HOW QUICKLY WILL
THE TROUGH OVER MI TODAY BECOME ENTRAINED WITH THE CIRCULATION
OVER ATLANTIC CANADA AND CLOSE OFF. THE NAM, SREF AND TO A MORE
LIMITED EXTENT THE 12Z ECMWF SHOW THE TROUGH CLOSING OFF
SOONEST, PRODUCING A SLOW-MOVING GALE LOW SOUTH OF NANTUCKET,
WHICH THEN SLOWLY MEANDERS NNE INTO MONDAY. WERE THIS TO VERIFY,
MUCH OF SOUTHEAST NEW ENGLAND WOULD SEE A CHILLY, RAW AND WET
SUNDAY AND MONDAY WITH PERIODS OF RAIN AND NE GUSTS TO NEAR GALE
FORCE (E.G. NAM SHOWS 950 MB NE WINDS 55-60 KT). THE RISK FOR
RAIN IN THAT OUTCOME WOULD ALSO EXTEND AS FAR NORTH AS THE MASS
PIKE, AND ESPECIALLY EASTERN MA. THOUGH I THINK IT'S TOO EARLY
TO OUTRIGHT DISMISS THIS, IT DOESN'T HAVE MUCH SUPPORT FROM THE
GFS/CANADIAN/MORE RECENT 00Z ECMWF CAMP, WHICH CLOSES OFF THE
MID- LEVEL SHORTWAVE TOO LATE TO A MORE OFFSHORE SOLUTION,
KEEPING LIGHTER RAIN SHOWERS TO THE COASTAL WATERS, MARTHA'S
VINEYARD, NANTUCKET AND CAPE COD WITH NE BREEZES, WITH MOSTLY
CLOUDY BUT GENERALLY DRY CONDITIONS ELSEWHERE FOR SUNDAY INTO
MONDAY. CLUSTER ANALYSES ALSO SUGGEST THE NAM SOLUTION IS MORE
OF AN OUTLIER. WILL WEIGHT THE FORECAST CLOSER TO THE
GFS/CANADIAN MORE OFFSHORE IDEA, BUT STILL SHOWS CHANCE TO
BORDERLINE LIKELY POP AND NE WINDS INCREASING SUNDAY NIGHT INTO
MONDAY FOR SOUTHEAST NEW ENGLAND. IF OTHER GUIDANCE WERE TO COME
ON BOARD WITH THE NAM IN SUBSEQUENT GUIDANCE, THEN THE
POTENTIAL FOR MORE SUBSTANTIAL FORECAST CHANGES WOULD BE IN THE
CARDS. ASTRO TIDES ARE DECREASING SO REALLY NO RISK FOR COASTAL
FLOODING. HIGHS IN THE 40S TO LOWER-MID 50S SUNDAY, COOLEST
SOUTHEAST NEW ENGLAND, AND IN THE 50S TO LOWER 60S FOR MONDAY,
THOUGH IN THE LOWER 50S FOR EASTERN MA WITH NE BREEZES.
KEY MESSAGE 3...DRY WEATHER WITH ONSHORE BREEZES RESUME EARLY TO
MIDDLE OF NEXT WEEK WITH A WARMING TREND TO TEMPS, BEFORE
WEATHER TURNS MORE UNSETTLED LATE IN THE WEEK.
HIGH PRESSURE THEN REASSERTS ITSELF ONCE THE COASTAL LOW PULLS
AWAY EITHER MONDAY OR TUESDAY - VIEWED AS MORE LIKELY MONDAY.
THIS BRINGS WHAT SHOULD BE NICE WEATHER WITH ONSHORE BREEZES AND
TEMPERATURES GRADUALLY MODIFYING, ALTHOUGH STILL SLIGHTLY
COOLER THAN NORMAL. OUR WEATHER PATTERN THEN TURNS MORE
UNSETTLED FOR MID TO LATE IN THE WEEK, WITH A POSSIBLE RISK FOR
COASTAL CLOUDINESS/RAIN SHOWERS WEDNESDAY, AND THEN TROUGHING
AND A COLD FRONT AROUND THURSDAY/FRIDAY.
AVIATION /12Z SATURDAY THROUGH WEDNESDAY/
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
TODAY AND TONIGHT: HIGH CONFIDENCE.
VFR, INCREASING COVERAGE OF MID TO HIGH CLOUDS. CEILINGS START
TO LOWER TO LOWER-END VFR/MVFR LEVELS NEAR BDL AROUND 22-00Z
WITH RAIN SHOWERS. VFR VISIBILITY FOR MOST. RAIN SHOWERS AND
MVFR CEILINGS THEN EXPAND SOUTHEAST TO NEAR PVD OVERNIGHT. NE
WINDS 5-10 KT SHIFTING TO SE LATE THIS MORNING INTO THIS
AFTERNOON, THEN BECOMING LIGHT SOUTHERLY (CALM AT TIMES) EARLY
TONIGHT BEFORE RETURNING BACK TO NE 5-10 KT TOWARD DAYBREAK
SUNDAY.
SUNDAY AND SUNDAY NIGHT: HIGH CONFIDENCE FOR MOST, BUT LOW TO
MODERATE CONFIDENCE FOR THE CAPE AND ISLANDS.
BKN/OVC VFR FOR MOST, WITH NE WINDS 5-10 KT. LOWEST
CEILINGS/CATEGORIES (MVFR LEVELS) AND STRONGER NE WINDS AROUND
10-15 KT FOR THE CAPE AND ISLANDS, TO GO ALONG WITH PERIODS OF
SHOWERS AS LOW PRESSURE PASSES TO OUR SOUTH. IF THE LOW PRESSURE
WERE TO TRACK CLOSER TO SOUTHERN NEW ENGLAND'S WATERS, THEN
CEILINGS WOULD TREND CLOSER TO IFR/LIFR, MVFR VISBY RAIN AND NE
WINDS IN THE 20 KT RANGE FOR THE CAPE AND ISLANDS, WITH MVFR
CEILINGS NORTHWARD TO THE I-95 CORRIDOR, BUT THIS IS VIEWED AS
UNLIKELY.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF. VFR THROUGH THE PERIOD.
NE WINDS 5-10 KT TREND TO ESE BY LATE MORNING, THEN SHIFTING TO
LIGHT SOUTHERLY (CALM AT TIMES?) LATE TONIGHT BEFORE RETURNING
BACK TO NE OVERNIGHT.
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF. VFR THROUGH AT LEAST
LATE THIS AFTERNOON. CEILINGS LOWER TO MVFR RANGES WITH VFR
VISBY RAIN SHOWERS 23-01Z, WHICH CONTINUE THROUGH 12Z SUNDAY.
ESE WINDS TREND LIGHT SOUTHERLY TONIGHT, THEN RETURN TO ENE
WINDS OVERNIGHT.
OUTLOOK /SUNDAY THROUGH WEDNESDAY/...
SUNDAY: MAINLY VFR, WITH LOCAL MVFR POSSIBLE. SLIGHT CHANCE RA.
SUNDAY NIGHT THROUGH MONDAY: VFR. BREEZY. SLIGHT CHANCE SHRA.
MONDAY NIGHT THROUGH TUESDAY: VFR. BREEZY.
TUESDAY NIGHT THROUGH WEDNESDAY: MAINLY VFR, WITH LOCAL MVFR
POSSIBLE. CHANCE SHRA.
MARINE
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
TODAY AND TONIGHT: HIGH CONFIDENCE.
WINDS AND SEAS ARE BELOW SCA CRITERIA THROUGH TONIGHT, WITH E/SE
WINDS AROUND 10-15 KT AND SEAS 3 FT OR LESS, BUILDING TO AROUND
4 FT ON SOUTHERN WATERS. DRY WEATHER TODAY, ALTHOUGH A RISK FOR
SHOWERS ON THE SOUTHERN WATERS TONIGHT.
SUNDAY AND SUNDAY NIGHT: MODERATE CONFIDENCE.
COASTAL LOW PRESSURE PASSES OVER THE SOUTHERN WATERS SUNDAY INTO
SUNDAY NIGHT. EXPECT INCREASING NORTHEAST WINDS TO AROUND
20-25 KT AND BUILDING SEAS, WHICH COULD WARRANT SCAS ON THE
SOUTHERN WATERS IF THE LOW PRESSURE PASSES CLOSER TO SOUTHERN
NEW ENGLAND'S WATERS. NE WINDS AROUND 10-20 KT NORTHEAST WATERS.
THOUGH IT IS UNLIKELY, A PERIOD OF STRONGER NORTHEAST WINDS
POSSIBLY INTO THE 30 KT RANGE COULD DEVELOP SUNDAY NIGHT
SOUTHEAST OF CAPE COD. RAIN SHOWERS SOUTHERN WATERS, BUT MAINLY
DRY EASTERN WATERS.
OUTLOOK /SUNDAY THROUGH WEDNESDAY/...
SUNDAY: WINDS LESS THAN 25 KT. CHANCE OF RAIN.
SUNDAY NIGHT: WINDS LESS THAN 25 KT. SEAS LOCALLY APPROACHING
5 FT. CHANCE OF RAIN SHOWERS.
MONDAY: LOW RISK FOR SMALL CRAFT ADVISORY WINDS WITH GUSTS UP
TO 25 KT. AREAS OF SEAS APPROACHING 5 FT. CHANCE OF RAIN
SHOWERS.
MONDAY NIGHT: WINDS LESS THAN 25 KT. AREAS OF SEAS APPROACHING
5 FT. SLIGHT CHANCE OF RAIN SHOWERS.
TUESDAY: WINDS LESS THAN 25 KT. LOCAL ROUGH SEAS. SLIGHT CHANCE
OF RAIN SHOWERS.
TUESDAY NIGHT: WINDS LESS THAN 25 KT. AREAS OF ROUGH SEAS.
SLIGHT CHANCE OF RAIN SHOWERS.
WEDNESDAY: WINDS LESS THAN 25 KT. ROUGH SEAS UP TO 8 FT. CHANCE
OF RAIN SHOWERS.
BOX WATCHES/WARNINGS/ADVISORIES
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.
DISCUSSION...LOCONTO
AVIATION...BELK/LOCONTO
MARINE...LOCONTO
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