537
FXUS61 KBOX 270707
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
307 AM EDT MON APR 27 2026
WHAT HAS CHANGED
ADDED SMALL CRAFT ADVISORIES FOR THE NORTHERN WATERS TUESDAY, WHILE
EXTENDING THE EXISTING SMALL CRAFT ADVISORIES THROUGH TUESDAY
NIGHT.
KEY MESSAGES
- SUNNY AND DRY WEATHER EARLY THIS WEEK. ABOVE NORMAL
TEMPERATURES FOR WESTERN/INTERIOR NEW ENGLAND, BUT REMAINING
QUITE A BIT COOLER NEAR THE COAST WITH SEABREEZES.
- UNSETTLED WEATHER AROUND WEDNESDAY NIGHT AND THURSDAY WITH A
WELCOMED SOAKING RAIN LOOKING LIKELY.
- REMAINS UNSETTLED FRIDAY INTO THE WEEKEND WITH PARTLY TO
MOSTLY CLOUDY WEATHER, COOLER THAN NORMAL TEMPERATURES AND
POP-UP SHOWERS.
DISCUSSION
KEY MESSAGE 1...SUNNY AND DRY WEATHER EARLY THIS WEEK. ABOVE NORMAL
TEMPERATURES FOR WESTERN/INTERIOR NEW ENGLAND, BUT REMAINING QUITE A
BIT COOLER NEAR THE COAST WITH SEABREEZES.
HIGH PRESSURE RIDGING IN FROM COASTAL ME/NH IS LEADING TO CLEAR
SKIES, LIGHT TO CALM WINDS AND A COOL EVENING FOR MOST OF SOUTHERN
NEW ENGLAND, AND WILL REMAIN IN PLACE THE NEXT COUPLE DAYS. SOME
RESIDUAL CLOUD COVER FROM DISTANT COASTAL LOW WILL BE GRADUALLY
PEELING OFF TOWARD THE SOUTHEAST THROUGH THE MORNING HOURS.
THIS SETS THE STAGE FOR A COUPLE OF STELLAR COUPLE DAYS FOR US TODAY
AND TOMORROW TO OPEN UP THE WORKWEEK. BOTH DAYS ARE GENERALLY
SIMILAR - WITH FULL SUN, DEEP BLUE SKIES WITH ONSHORE FLOW AND
SEABREEZES FOR THE EAST COAST (AND POTENTIALLY THE SOUTH COAST TOO),
TO GO ALONG WITH GOOD RADIATIONAL COOLING BOTH NIGHTS. AWAY FROM THE
COAST HIGHS SHOULD REACH INTO THE 60S, WITH SOME LOWER 70S IN THE CT
VALLEY, BUT NEAR THE COASTS, HIGHS WILL BE KEPT IN THE LOWER TO MID
50S. PBL FLOW IS NEXT TO NIL WITH STRONG CONFIDENCE IN SEABREEZE
DEVLEOPMENT, AND IT MAY PENETRATE QUITE A WAYS INLAND AND BRING SOME
MODEST COOLING THIS AFTERNOON TO I-495. REALLY NICE COUPLE DAYS FOR
OUTDOOR ACTIVITIES. LOWS EACH NIGHT IN THE MID 30S TO LOW 40S.
THE ONE POTENTIAL FLY IN THE OINTMENT COMES EITHER LATE TUESDAY OR
TUESDAY NIGHT. MOISTURE FROM THE OFFSHORE LOW LOOKS TO ROTATE BACK
WESTWARD, WITH GUIDANCE VARYING ON WHEN THAT MIGHT OCCUR, WHICH
COULD BRING LOW CLOUDS AND POSSIBLE DRIZZLE TO EAST COASTAL MA WHEN
IT DOES SET IN. THE TIMING WILL PROBABLY BE TOUGH TO PIN DOWN OVER
THE NEXT COUPLE DAYS BUT A BEST ESTIMATE LOOKS TO BE SOMETIME
TUESDAY NIGHT. REALLY NOT A SIGNIFICANT IMPACT THOUGH, ASIDE FROM
AVIATION.
KEY MESSAGE 2...UNSETTLED WEATHER AROUND WEDNESDAY NIGHT AND
THURSDAY WITH A WELCOMED SOAKING RAIN LOOKING LIKELY.
THE MORE ACTIVE PERIOD OF WEATHER TAKES SHAPE LATE WEDNESDAY
NIGHT AND ESPECIALLY INTO THURSDAY. OVERCAST SKIES BUT MAINLY
DRY WEATHER HOLDS ON FOR WED, BUT BY LATER WEDNESDAY NIGHT INTO
THURSDAY, A FRONTAL OCCLUSION WITH POSSIBLE SECONDARY LOW
PRESSURE DEVELOPMENT ALONG IT SWEEPS NNE THROUGH SOUTHERN NEW
ENGLAND. PRETTY ROBUST DYNAMICS ACTING ON A 1" PWAT AIRMASS
SHOULD BRING A WELCOMED SOAKING RAIN. SOME OF THE DETAILS ARE
STILL UNCERTAIN THIS FAR OUT, INCLUDING IF AND HOW STRONG MIGHT
A SECONDARY LOW PRESSURE DEVELOPING ON THE FRONT MIGHT BE. THAT
WOULD AFFECT RAIN AMOUNTS AND ALSO ENHANCED ESE WINDS. DID LOOK
BRIEFLY AT COASTAL FLOODING AS ASTRO TIDES START TO COME UP
THURSDAY TOO, BUT IT WOULD TAKE ABOUT A 2 FT SURGE TO GET MOST
AREAS TO MINOR COASTAL FLOODING FOR THE EVENING HIGH TIDES AND
AN EARLY LOOK SUGGESTS VALUES AROUND 1-1.3 FT, THUS LIKELY FALLING
SHORT. STILL, A GOOD SOAKING RAIN WITH MODERATE TO HIGH PROBS
OF 24 HOUR RAIN OF AT LEAST A HALF INCH, AND LOWER TO MODERATE
PROBS OF 24 HOUR RAINS OF AT LEAST AN INCH.
KEY MESSAGE 3...REMAINS UNSETTLED FRIDAY INTO THE WEEKEND WITH
PARTLY TO MOSTLY CLOUDY WEATHER, COOLER THAN NORMAL TEMPERATURES AND
POP-UP SHOWERS.
BEYOND THURSDAY...WEATHER PATTERN REMAINS UNSETTLED WITH
CYCLONIC FLOW ALOFT GOVERNING THE AREA, BRINGING A RETURN TO
COOLER THAN NORMAL TEMPERATURES AND AT LEAST SOME PARTIAL
CLOUDINESS TO OPEN THE FIRST COUPLE DAYS OF MAY. THE QUESTION IS
IF WE CAN GENERATE ANY INSTABILITY SHOWERS FOR FRIDAY INTO THE
WEEKEND UNDERNEATH THE TROUGH. EARLIER 12Z GUIDANCE WAS HINTING
AT THIS MORE BULLISHLY, BUT THE RECENT 00Z GUIDANCE HAS BACKED
OFF AND SHUNTS MOST OF THE MOISTURE OFF TOWARDS NORTHERN NEW
ENGLAND. IF SHOWERS WERE TO DEVELOP, THEY WOULDN'T NECESSARILY
BE WASHOUTS BUT COULD PRODUCE SOME GRAUPEL GIVEN THE
ANOMALOUSLY COLD AIRMASS FOR EARLY MAY (850 MB TEMPS -1 TO -4C).
HIGHS IN THE MID TO UPPER 50S WITH A MODEST WNW WIND.
AVIATION /06Z MONDAY THROUGH FRIDAY/
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
06Z TAF UPDATE:
THROUGH 12Z MONDAY: HIGH CONFIDENCE.
MAINLY VFR; A SMALL CHANCE FOR PATCHY MIST/FOG IN THE TYPICALLY
FAVORED WESTERN RIVER VALLEYS TOWARD DAYBREAK. LIGHT TO CALM
WINDS FOR MOST, OTHERWISE NE WINDS 5-10 KT NEAR THE EAST COAST.
TODAY AND TUESDAY: HIGH CONFIDENCE.
VFR. NE WINDS AROUND 10-15 KT WITH GUSTS TO 25 KT CAPE AND
ISLANDS FOR BOTH DAYS; OTHERWISE NE TO E WINDS 5-10 KT,
LIGHTEST IN THE INTERIOR AND ON THE HIGHER END OF THAT RANGE FOR
EASTERN MA.
TUESDAY NIGHT: HIGH CONFIDENCE OVERALL, BUT MODERATE ALONG THE
EASTERN COAST.
VFR FOR MOST. POTENTIAL FOR COASTAL MVFR-IFR STRATUS AS MOISTURE
WRAPS BACK IN FROM THE OCEAN WATERS, BUT ITS TIMING IS
UNCERTAIN. LIGHT N/NE WINDS.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF. NE TO E WINDS AROUND
5-10 KT GENERALLY PREVAIL TODAY. THERE MIGHT BE A POSSIBLE
PERIOD OF SE/SSE WINDS AROUND 23Z MONDAY-02Z TUESDAY BEFORE
WINDS RETURN TO LIGHT NE TONIGHT.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK /TUESDAY THROUGH FRIDAY/...
TUESDAY: VFR. BREEZY.
TUESDAY NIGHT THROUGH WEDNESDAY: VFR. SLIGHT CHANCE SHRA.
WEDNESDAY NIGHT: MAINLY VFR, WITH LOCAL IFR POSSIBLE. CHANCE
SHRA.
THURSDAY: MVFR/IFR CONDITIONS POSSIBLE. BREEZY. SHRA, SLIGHT
CHANCE TSRA.
THURSDAY NIGHT: MAINLY VFR, WITH LOCAL MVFR POSSIBLE. WINDY
WITH GUSTS UP TO 30 KT. CHANCE SHRA.
FRIDAY: MAINLY VFR, WITH LOCAL MVFR POSSIBLE. WINDY WITH LOCAL
GUSTS UP TO 30 KT. SLIGHT CHANCE SHRA.
MARINE
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
NORTHEAST WINDS WILL BE STRONGEST TODAY OVER THE SOUTHEAST
WATERS ADJACENT TO CAPE COD, WITH GUSTS IN THE 25 KT RANGE AND
SEAS BUILDING TO AROUND 4-6 FT. OTHERWISE, NORTHEAST WINDS AND
SEAS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY LEVELS TODAY.
NE TO N WINDS AROUND 15-20 KT TONIGHT INTO TUESDAY, HIGHEST
EASTERN/SOUTHEAST WATERS. THE MAIN ISSUE IS THAT SEAS FROM A
DISTANT COASTAL LOW NEAR THE MARITIMES WILL BE BUILDING ON MOST
OF THE EASTERN AND SOUTHERN OUTER WATERS; THIS HAS PROMPTED
EXTENDING THE EXISTING OCEAN WATERS SCAS THROUGH TUESDAY NIGHT
WHILE ADDING THE NORTHERN OUTER WATERS. SEAS BUILDING TO AROUND
6-9 FT BY TUESDAY NIGHT.
OUTLOOK /TUESDAY THROUGH FRIDAY/...
TUESDAY: WINDS LESS THAN 25 KT. AREAS OF ROUGH SEAS.
TUESDAY NIGHT THROUGH WEDNESDAY: WINDS LESS THAN 25 KT. AREAS
OF ROUGH SEAS. SLIGHT CHANCE OF RAIN SHOWERS.
WEDNESDAY NIGHT: WINDS LESS THAN 25 KT. LOCAL ROUGH SEAS.
CHANCE OF RAIN SHOWERS.
THURSDAY: WINDS LESS THAN 25 KT. LOCAL ROUGH SEAS. RAIN
SHOWERS, SLIGHT CHANCE OF THUNDERSTORMS.
THURSDAY NIGHT: LOW RISK FOR SMALL CRAFT ADVISORY WINDS WITH
GUSTS UP TO 25 KT. SEAS UP TO 5 FT. CHANCE OF RAIN SHOWERS.
FRIDAY: LOW RISK FOR SMALL CRAFT ADVISORY WINDS WITH GUSTS UP
TO 25 KT. SEAS UP TO 5 FT. SLIGHT CHANCE OF RAIN SHOWERS.
BOX WATCHES/WARNINGS/ADVISORIES
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 8 AM THIS MORNING TO 8 PM EDT THIS
EVENING FOR ANZ232.
SMALL CRAFT ADVISORY FROM 2 AM TUESDAY TO 2 AM EDT WEDNESDAY
FOR ANZ250.
SMALL CRAFT ADVISORY FROM 8 AM THIS MORNING TO 2 AM EDT
WEDNESDAY FOR ANZ254>256.
DISCUSSION...LOCONTO
AVIATION...LOCONTO
MARINE...LOCONTO
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