379
FXUS61 KBOX 311136
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
736 AM EDT TUE MAR 31 2026
WHAT HAS CHANGED
WAVY FRONTAL BOUNDARY WILL LEAD TO LARGE SWINGS IN TEMPERATURE
AROUND MIDWEEK INTO THE WEEKEND WITH SEVERAL RAIN CHANCES.
KEY MESSAGES
- SHOWERS WITH BRIEF HEAVY DOWNPOURS THIS MORNING WITH PERHAPS
AN ISOLATED T-STORM OR TWO.
- EXPECTING A VERY SHARP TEMPERATURE GRADIENT TUES WITH A
SECONDARY ROUND OF SHOWERS IN THE PM.
- MILDER BUT UNSETTLED PATTERN LATER THIS WEEK BRINGS SHOWERS
FROM TIME TO TIME.
- WATCHING MAINSTEM CONNECTICUT RIVER FOR POSSIBLE MINOR RIVER
FLOODING FROM HARTFORD THROUGH MIDDLETOWN THIS WEEKEND.
DISCUSSION
KEY MESSAGE 1...SHOWERS WITH BRIEF HEAVY DOWNPOURS THIS MORNING
WITH PERHAPS AN ISOLATED T-STORM OR TWO.
CONTINUING TO EYE A QUICK MOVING ROUND OF RAIN SHOWERS IN THE
EARLY MORNING HOURS OF TUESDAY AS A MID-LEVEL SHORTWAVE MOVES
THROUGH. LATEST MODEL GUIDANCE SEEMS TO INDICATE A DELAYED
ARRIVAL COMPARED TO EARLIER IN THE EVENING... THINKING MAYBE
MORE AFTER SUNRISE INSTEAD OF JUST BEFORE... ESPECIALLY FOR
EASTERN MA. STILL LOOKS TO BE JUST ENOUGH INSTABILITY TO
POSSIBLY POP A RUMBLE OF THUNDER OR TWO, ESPECIALLY LATER IN THE
MORNING, BUT PROBS ARE STILL QUITE LOW... HREF INDICATING
AROUND 10 PERCENT OR SO. NOT EVERYWHERE WILL SEE SHOWERS THIS
MORNING, BUT SOME AREAS COULD SEE BRIEF HEAVY DOWNPOURS, AND THE
TUESDAY MORNING COMMUTE IS LIKELY TO BE IMPACTED.
KEY MESSAGE 2...EXPECTING A VERY SHARP TEMPERATURE GRADIENT
TUES WITH A SECONDARY ROUND OF SHOWERS IN THE PM.
ALREADY STARTING TO SEE A BACKDOOR FRONT HOVERING OVER NORTHERN
NEW ENGLAND, AND EXPECTING THAT TO DROP SOUTH INTO SOUTHERN NEW
ENGLAND LATER TUES. OVERNIGHT MODEL GUIDANCE HAS SOLIDIFIED IN
INDICATING NE MA/MERRIMACK VALLEY COULD SEE THAT FRONT DROP
THROUGH AS EARLY AS MID-DAY OR VERY EARLY AFTERNOON. STILL SOME
UNCERTAINTY IN HOW FAR SOUTH/EAST THE FRONT WILL DROP WHICH
MAKES THE TEMPERATURE FORECAST TRICKY, WITH A 25-30 DEGREE
TEMPERATURE DIFFERENCE POSSIBLE ALONG THE BOUNDARY. STILL
THINKING NE MA HAS A CHANGE AT SEEING THE LOW 50S, AND
CONFIDENCE IN THE LOWER CT VALLEY REACHING INTO THE LOWER 70S IS
HIGH. ONCE THE FRONT MOVES IN, TEMPS WILL LIKELY DROP
QUICKLY... INTO THE LOW 40S, POSSIBLE THE UPPER 30S.
EXPECTING TO SEE A FEW HOURS OF DRYING OUT AFTER THIS MORNING'S
QUICK PUSH OF SHOWERS, BUT CONFIDENCE IS INCREASING IN A
SECONDARY ROUND OF SHOWERS (AND POSSIBLE T-STORMS) DEVELOPING
LATER IN THE AFTERNOON/EVENING, ESPECIALLY ACROSS THE INTERIOR
WITH STORMS INITIATING ACROSS UPSTATE NY. THE LATEST GUIDANCE
SEEMS SPLIT WITH SOME MODELS CONTINUING TO INDICATE A LOW-END
SEVERE POSSIBILITY LINGERING INTO SOUTHERN NEW ENGLAND AND
OTHERS KEEPING THE CONVECTION IN VT AND NH. REGARDLESS,
INSTABILITY REMAINS RATHER UNIMPRESSIVE WITH ONLY POCKETS OF
CAPE NEAR 500 J/KG SCATTERED ACROSS INTERIOR SNE. WE'LL CONTINUE
TO MONITOR THROUGHOUT THE MORNING, BUT THE MOST LIKELY SCENARIO
CONTINUES TO BE A FEW SPOTS OF WEAKENING CONVECTION MOVING INTO
THE REGION.
KEY MESSAGE 3...MILDER BUT UNSETTLED PATTERN LATER THIS WEEK
BRINGS SHOWERS FROM TIME TO TIME.
SUBTROPICAL RIDGE IS EXPECTED TO BUILD OFF EAST COAST LATER
THIS WEEK AND INTO WEEKEND, WHILE MEAN TROUGH SETS UP NEAR GREAT
LAKES, RESULTING IN BROAD AND MOIST SW FLOW ALOFT. PRESENCE OF
FRONTAL BOUNDARY NEARBY GIVES AN UNSETTLED LOOK TO MUCH OF
PERIOD FROM THURSDAY THROUGH THE WEEKEND AS IT LIFTS NORTH AND
SAGS SOUTHWARD FROM TIME TO TIME, BUT FORECAST WILL PROBABLY
APPEAR MORE PESSIMISTIC WITH CHANCES OF RAIN EACH DAY, WHILE IN
REALITY SHOWERS WILL BE TIED TO PASSAGE OF SEVERAL WEAK SHORT
WAVES AND POSITION OF FRONT ITSELF, MEANING IT WON'T RAIN ALL OF
THE TIME.
DEPENDING UPON THE EXACT LOCATION OF FRONT, IT AT LEAST APPEARS
RIGHT NOW THAT SOME WARMER DAYS ARE AHEAD, ESPECIALLY OVER THE
WEEKEND WHEN TEMPERATURES POSSIBLY REACH THE 70S PER ENSEMBLE
PROBABILITIES. FORECAST REFLECTS A BIT OF A COMPROMISE RIGHT NOW
GIVEN UNCERTAINTY IN POSITION OF FRONT AND WILL SHOW
TEMPERATURES THAT ARE A LITTLE COOLER.
KEY MESSAGE 4...WATCHING MAINSTEM CONNECTICUT RIVER FOR
POSSIBLE MINOR RIVER FLOODING FROM HARTFORD THROUGH MIDDLETOWN
THIS WEEKEND.
THE COMBINATION OF RAINFALL AND UPSTREAM SNOWMELT IS EXPECTED
TO LEAD TO RISES ALONG THE MAINSTEM CONNECTICUT RIVER OVER THE
NEXT SEVERAL DAYS. ENSEMBLE RIVER FORECASTS SHOW LOW CHANCES
(30-40%) OF REACHING MINOR FLOOD ALONG LOWER CONNECTICUT RIVER
FROM HARTFORD TO MIDDLETOWN THIS WEEKEND, BUT THAT APPEARS TO BE
A HIGHER-END SCENARIO RIGHT NOW. IT IS MORE LIKELY THAT THE
RIVER WILL REMAIN WITHIN ITS BANKS BUT WE WILL NEED TO ASSESS
RAINFALL AND SNOWMELT OVER NEXT COUPLE OF DAYS TO GET A BETTER
SENSE OF POTENTIAL IMPACTS.
AVIATION /12Z TUESDAY THROUGH SATURDAY/
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
12Z TAF UPDATE...MODERATE CONFIDENCE EXCEPT LOW CONFIDENCE IN
TIMING OF ANY PRECIPITATION.
MAINLY VFR THIS MORNING...BUT CLUSTERS OF SHOWERS WITH
DOWNPOURS WITH EVEN PERHAPS A RUMBLE OF THUNDER WILL RESULT IN
BRIEFLY LOWER LOCALIZED CONDITIONS. OTHERWISE...SW WINDS GUST 20
TO 30 KNOTS WITH THE STRONGEST NEAR THE SOUTH COAST THIS
MORNING.
SW WINDS PREVAIL UNTIL A BACKDOOR COLD FRONT CROSSES EASTERN MA
IN THE 17Z TO 20Z TIME FRAME. THIS SHOULD REACH CENTRAL MA AFTER
21Z/22Z. IT WILL THEN STALL AND GRADUALLY BEGIN TO MOVE BACK AS
A WARM FRONT LATER TONIGHT. THEN THE WARM FRONT FLIPS BACK TO A
BACKDOOR COLD FRONT AND SWEEPS THROUGH THE ENTIRE REGION DURING
THE DAY WEDNESDAY. VFR CONDITIONS WILL DOMINATE SOUTHWEST OF
THE BACKDOOR COLD FRONT...BUT LOW CLOUDS WILL RESULT IN MVFR-
IFR CEILINGS TO THE NORTHEAST OF THE BACKDOOR FRONT.
WE HAVE ONE CLUSTER OF SHOWERS MOVING THROUGH THIS MORNING.
MODELS REALLY STRUGGLING WITH TIMING OF ADDITIONAL SHOWERS...BUT
PERHAPS ANOTHER ROUND SOMEWHERE AROUND MID-AFTERNOON WITH THE
GREATEST RISK OVERNIGHT. THESE ADDITIONAL SHOWERS MAY CONTAIN A
FEW THUNDERSTORMS TOO ALONG WITH BRIEF DOWNPOURS.
KBOS TERMINAL...MODERATE CONFIDENCE IN TAF EXCEPT LOW CONFIDENCE
IN TIMING OF ANY SHOWERS/ISOLATED T-STORM RISK. WE THINK THE
BACKDOOR COLD FRONT CROSSES THE REGION IN THE 18Z/19Z TIME
FRAME...WHICH WILL BE FOLLOWED BY MVFR-IFR CEILINGS.
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF BUT LOW CONFIDENCE IN
TIMING OF ANY SHOWERS/ISOLATED T-STORM RISK.
OUTLOOK /WEDNESDAY NIGHT THROUGH SATURDAY/...
WEDNESDAY NIGHT: MVFR/IFR CONDITIONS POSSIBLE. BREEZY. SHRA
LIKELY.
THURSDAY THROUGH THURSDAY NIGHT: MVFR/IFR CONDITIONS POSSIBLE.
BREEZY. CHANCE SHRA.
FRIDAY: MAINLY VFR, WITH LOCAL IFR POSSIBLE. BREEZY.
FRIDAY NIGHT THROUGH SATURDAY: BREEZY. SLIGHT CHANCE RA.
MARINE
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
EXPECTING ANOTHER ROUND OF 20-30KT SW WIND GUSTS ALONG SOUTH
COASTAL WATERS BUT ALSO AHEAD OF BACKDOOR FRONT INTO CAPE COD
BAY AND ON OUTER E MA WATERS TODAY. COULD SEE SOME BRIEF
MARGINAL GALE FORCE GUSTS AS WELL. MAINTAINING SMALL CRAFT
ADVISORIES FOR THESE WATERS TODAY AND TONIGHT, EXCEPT THROUGH
WEDNESDAY ON OUTER WATERS WHERE SEAS WILL TAKE LONGER TO
SUBSIDE.
FRONT DROPS SOUTH AND BRINGS RAPID WIND SHIFT TO N/NE, STARTING
NEAR MERRIMACK RIVER AROUND MIDDAY AND PROBABLY SETTLING NEAR
PROVIDENCE AND PLYMOUTH BY LATE AFTERNOON. IT RETURNS NORTHWARD
TONIGHT BEFORE DROPPING BACK SOUTH WEDNESDAY.
OUTLOOK /WEDNESDAY NIGHT THROUGH SATURDAY/...
WEDNESDAY NIGHT: WINDS LESS THAN 25 KT. SEAS UP TO 5 FT. RAIN
SHOWERS LIKELY. LOCAL VISIBILITY 1 NM OR LESS.
THURSDAY: LOW RISK FOR SMALL CRAFT ADVISORY WINDS WITH GUSTS UP
TO 25 KT. SEAS UP TO 5 FT. CHANCE OF RAIN SHOWERS.
THURSDAY NIGHT: WINDS LESS THAN 25 KT. AREAS OF SEAS
APPROACHING 5 FT. 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: LOW RISK FOR SMALL CRAFT ADVISORY WINDS WITH
GUSTS UP TO 25 KT. SEAS UP TO 5 FT. SLIGHT CHANCE OF RAIN.
SATURDAY: WINDS LESS THAN 25 KT. AREAS OF SEAS APPROACHING
5 FT. SLIGHT CHANCE OF RAIN.
BOX WATCHES/WARNINGS/ADVISORIES
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ231-
250.
SMALL CRAFT ADVISORY UNTIL 7 PM EDT WEDNESDAY FOR ANZ232>235-
237.
SMALL CRAFT ADVISORY UNTIL 2 PM EDT WEDNESDAY FOR ANZ236.
SMALL CRAFT ADVISORY UNTIL 6 AM EDT THURSDAY FOR ANZ254>256.
DISCUSSION...MCMINN/JWD
AVIATION...FRANK
MARINE...JWD
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