827
FXUS61 KBOX 130757
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
357 AM EDT MON APR 13 2026
WHAT HAS CHANGED
NO SIGNIFICANT CHANGES TO THE FORECAST.
KEY MESSAGES
- CONSIDERABLE CLOUDS, GUSTY SW WINDS, BUT NOTHING MORE THAN A FEW
BRIEF SPOT SHOWERS TODAY. HIGHS MAINLY IN THE 70S, BUT COOLER
UPPER 50S/60S TOWARDS THE SOUTH COAST.
- UNSEASONABLE SUMMERLIKE WARMTH TUE & WED WITH HIGHS MAINLY IN THE
UPPER 70S AND 80S BUT COOLER ON THE COAST AT TIMES ESPECIALLY
ACROSS NORTHEAST MA. SCATTERED DIURNALLY DRIVEN SHOWERS AND A FEW
T-STORMS POSSIBLE WITH EVEN A LOW RISK FOR ISOLATED SEVERE WEATHER.
- SUMMERLIKE WARMTH MAY PERSIST THU/FRI/SAT ACROSS PARTS OF THE REGION
WITH HIGHS IN THE U70S & 80S...BUT A BACKDOOR COLD FRONT MAY BRING MUCH
COOLER TEMPS AT TIMES ESPECIALLY ACROSS EASTERN & NORTHEAST MA.
A FEW SHOWERS POSSIBLE AT TIMES...BUT DRY WEATHER DOMINATES.
- A COLD FRONT CROSSES THE REGION SUN/SUN NIGHT WITH SOME
SHOWERS... BRINGING AN END TO THE SUMMERLIKE WARMTH BY THE
START OF THE NEXT WORK WEEK WITH MUCH COOLER TEMPS.
DISCUSSION
KEY MESSAGE 1...CONSIDERABLE CLOUDS, GUSTY SW WINDS, BUT NOTHING MORE
THAN A FEW BRIEF SPOT SHOWERS TODAY. HIGHS MAINLY IN THE 70S, BUT COOLER
UPPER 50S/60S TOWARDS THE SOUTH COAST.
A SHORTWAVE AND ASSOCIATED WARM FRONT CROSSES THE REGION TODAY. THE
ASSOCIATED SOUTHWEST 50+ KNOT LOW LEVEL JET IN THE WARM ADVECTION
PATTERN WILL RESULT IN CONSIDERABLE CLOUDINESS...BUT NOTHING MORE
THAN A FEW SPOT SHOWERS. NONETHELESS...EVEN WITH JUST A FEW PEEKS OF
SUNSHINE HIGHS SHOULD REACH INTO THE 70S FOR MUCH OF THE REGION WITH
UPPER 50S/60S NEAR THE SOUTH COAST, CAPE AND ISLANDS. DEWPOINTS
RISING ABOVE 50 WILL MAKE IT FEEL QUITE MILD COMPARED TO THIS
WEEKEND. WE ALSO EXPECT GUSTY SOUTHWEST WINDS ON THE ORDER OF 25 TO
35 MPH AND PERHAPS A FEW GUSTS NEAR 40 MPH NEAR THE CLIMO FAVORED
AREAS IN THE VICINITY OF THE UPPER CAPE.
KEY MESSAGE 2...UNSEASONABLE SUMMERLIKE WARMTH TUE & WED WITH HIGHS
MAINLY IN THE UPPER 70S AND 80S BUT COOLER ON THE COAST AT
TIMES ESPECIALLY ACROSS NORTHEAST MA. SCATTERED DIURNALLY DRIVEN SHOWERS
AND A FEW T-STORMS POSSIBLE WITH EVEN A LOW RISK FOR ISOLATED
SEVERE WEATHER.
HIGH CONFIDENCE IN SUMMERLIKE WARMTH FOR MUCH OF THE REGION...AT
LEAST AWAY FROM THE IMMEDIATE COAST TUE AND WED. AN UPPER LEVEL
RIDGE OF HIGH PRESSURE OVER THE GULF WILL RESULT IN WESTERLY FLOW
ALOFT WITH WELL ABOVE NORMAL HEIGHT FIELDS. HIGH TEMPERATURES SHOULD
BE IN THE UPPER 70S AND 80S IN MOST LOCATIONS...AT LEAST AWAY FROM
THE IMMEDIATE COAST. MARINE INFLUENCES NEAR THE IMMEDIATE SOUTH
COAST, CAPE AND ISLANDS WILL LIKELY HOLD HIGH TEMPS IN THE 60S
ACROSS THOSE LOCALES. IN ADDITION...A BACKDOOR COLD FRONT LURKING IN
THE VICINITY OF EASTERN MA MAY BRING LOCALIZED COOLER TEMPS AT TIMES
ALONG THE IMMEDIATE COAST. THIS IS ESPECIALLY TRUE ACROSS NORTHEAST
MA...WHERE TEMPS COULD FALL INTO THE UPPER 40S AND 50S IF THE HIGH
RESOLUTION NAM MODEL IS CORRECT BY WED.
WE ALSO SHOULD MENTION THAT GIVEN THE ANOMALOUS WARM AIRMASS IN
PLACE AND WESTERLY FLOW ALOFT...WE WILL NEED TO WATCH FOR SCATTERED
DIURNALLY DRIVEN SHOWERS AND A FEW THUNDERSTORMS TUE AND WED.
IN FACT...THE CSU MACHINE LEARNING PROBS EVEN INDICATING SOME LOW
PROBS OF SEVERE WEATHER. AND THE HREF ALSO DOES HAVE SOME 2-5 KM
UPDRAFT HELICITY SWATHS ACROSS WESTERN AND NORTHERN MA ON TUE. SO THERE
IS A LOW RISK FOR ISOLATED SEVERE WEATHER TUE AND WED AFTERNOON/EVENINGS.
IF IT WERE TO HAPPEN...WESTERN MA WOULD BE FAVORED AND PARTICULARLY WEST
OF I-91 GIVEN MAIN AXIS OF INSTABILITY WEST OF OUR REGION.
SO IN A NUTSHELL...HIGH CONFIDENCE IN SUMMERLIKE WARMTH IN THE UPPER
70S AND 80S TUE AND WED INLAND FROM THE COAST. HOWEVER...ALONG THE
COAST ESPECIALLY NORTHEAST MA THERE IS A LARGE RANGE IN POSSIBLE
OUTCOMES FROM TEMPS IN THE 40S/50S VS 70S/80S DEPENDING ON THE
LOCATION OF THE BACKDOOR COLD FRONT. WE WILL HAVE A BETTER IDEA AS
WE GET FURTHER INTO THE HIGH RESOLUTION MODEL DATA...BUT ACROSS
NORTHEAST MA AND ESPECIALLY EASTERN ESSEX COUNTY IT MAY END UP MUCH
COOLER AT TIMES THAN THE REST OF OUR REGION.
KEY MESSAGE 3...SUMMERLIKE WARMTH MAY PERSIST THU/FRI/SAT ACROSS
PARTS OF THE REGION WITH HIGHS IN THE U70S & 80S...BUT A BACKDOOR
COLD FRONT MAY BRING MUCH COOLER TEMPS AT TIMES ESPECIALLY ACROSS
EASTERN MA. A FEW SHOWERS POSSIBLE AT TIMES, BUT MAINLY DRY WEATHER
IS EXPECTED.
FORECAST UNCERTAINTY INCREASES DURING THE LATTER HALF OF THE WEEK.
THE UPPER LEVEL ATMOSPHERE REMAINS SIMILAR WITH WESTERLY FLOW ALOFT
AND WELL ABOVE NORMAL HEIGHT FIELDS. HOWEVER...A COUPLE WAVES OF LOW
PRESSURE TRACKING ACROSS NORTHERN NEW ENGLAND MAY FORCE THE BACKDOOR
COLD FRONT THAT HAS BEEN LURKING ACROSS NORTHEAST MA FURTHER
SOUTHWEST AT TIMES. THE QUESTION IS HOW FAR SOUTHWEST AND WHEN
EXACTLY. THE FURTHER BACK INTO THE INTERIOR YOU GET WILL BRING THE
GREATEST POTENTIAL FOR SUMMERLIKE WARMTH IN THE UPPER 70S AND 80S
CONTINUING. THE GREATEST RISK FOR THE COOLER TEMPS WILL BE ACROSS
EASTERN MA AND ESPECIALLY NORTHEAST MA. WE WILL NEED TO GET INTO
THE HIGH RESOLUTION MODEL TIME WINDOW TO HAVE A BETTER IDEA ON THIS
POTENTIAL.
A FEW SHOWERS ARE POSSIBLE AT TIMES...BUT DRY WEATHER SHOULD
DOMINATE THE VAST MAJORITY OF THE TIME.
KEY MESSAGE 4...A COLD FRONT CROSSES THE REGION SUN/SUN NIGHT WITH
SOME SHOWERS...BRINGING AN END TO THE SUMMERLIKE WARMTH BY THE
START OF THE NEXT WORK WEEK.
A COLD FRONT WILL FINALLY CROSS THE REGION SOMETIME SUN INTO SUN
NIGHT...PROBABLY WITH A PERIOD OF SHOWERS. WHILE TIMING OF THIS
FRONT REMAINS UNCERTAIN...THIS SHOULD FINALLY BRING AN END TO THE
UNSEASONABLE SUMMERLIKE WARMTH WITH MUCH COOLER TEMPS BY THE START
OF THE NEXT WORK WEEK.
AVIATION /07Z MONDAY THROUGH FRIDAY/
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
06Z TAF UPDATE...MODERATE CONFIDENCE
VFR CONDITIONS LIKELY DOMINATE THROUGH TUESDAY. HOWEVER...WE DO
EXPECT MVFR-IFR CIGS/VSBYS TO DEVELOP TOWARDS THE SOUTH COAST, CAPE,
ISLANDS THIS MORNING AND PERSIST INTO TONIGHT. THIS A RESULT OF THAT
HIGH DEWPOINT AIR ADVECTING OVER THE RELATIVELY COLD OCEAN. ACROSS
THE REST OF THE REGION...VFR CONDITIONS DOMINATE BUT A PERIOD OF
MVFR CEILINGS ARE POSSIBLE THIS MORNING. A FEW BRIEF SPOT SHOWERS
POSSIBLE AT TIMES TODAY...BUT DRY WEATHER DOMINATES. OTHERWISE...SW
WIND GUSTS OF 20 TO 30 KNOTS DEVELOP THIS MORNING WITH A FEW GUSTS
NEAR 35 KNOTS TOWARDS THE UPPER CAPE. LLWS WILL ALSO BE A CONCERN
ESPECIALLY INTO MID-MORNING BEFORE THE STRONGER GUSTS DEVELOP. WINDS
DIMINISH TONIGHT BUT REMAIN FROM A SW-WSW DIRECTION BUT GENERALLY 10
KNOTS OR LESS DURING THE OVERNIGHT HOURS.
VFR CONDITIONS DOMINATE TUE...BUT SCATTERED SHOWERS AND A FEW T-
STORMS WILL BE POSSIBLE LATE TUE INTO TUE EVENING WITH THE GREATEST
RISK ACROSS INTERIOR SOUTHERN NEW ENGLAND. THIS MAY BRING BRIEFLY
LOCALIZED LOWER CIGS/VSBYS. S-SW WINDS 7 TO 15 KNOTS BUT WITH SEA
BREEZES FOR A TIME ALONG PARTS OF THE IMMEDIATE EASTERN MA COAST
KBOS TERMINAL... MODERATE CONFIDENCE IN TAF.
KBDL TERMINAL... MODERATE CONFIDENCE IN TAF.
OUTLOOK /TUESDAY NIGHT THROUGH FRIDAY/...
TUESDAY NIGHT THROUGH WEDNESDAY: VFR. BREEZY. CHANCE SHRA,
ISOLATED TSRA.
WEDNESDAY NIGHT: VFR. CHANCE SHRA, ISOLATED TSRA.
THURSDAY: MAINLY VFR, WITH LOCAL MVFR POSSIBLE. CHANCE SHRA.
THURSDAY NIGHT: VFR. CHANCE SHRA.
FRIDAY: VFR. CHANCE SHRA, SLIGHT CHANCE TSRA.
MARINE
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
TODAY THROUGH TUESDAY...HIGH CONFIDENCE.
A MODEST SOUTHWEST LLJ WILL BRING SMALL CRAFT WIND GUSTS OF 30+
KNOTS AND CHOPPY SEAS TO ALL WATERS TODAY. WE DO EXPECT SOME 35 KNOT
WIND GUSTS IN THE CLIMO FAVORED AREAS NEAR BUZZARDS/CAPE COD BAYS
AND BID/ACK SOUNDS WHERE WE HAVE GALE WARNINGS POSTED. CORE OF LLJ
SHIFTS EAST OF THE REGION TONIGHT ALLOWING WINDS TO DROP BELOW SMALL
CRAFT THRESHOLDS TONIGHT AND REMAIN BELOW CRITERIA ON TUE. SEAS WILL
ALSO GRADUALLY SUBSIDE...BUT WILL TAKE UNTIL TUE AFTERNOON FOR SMALL
CRAFT SEAS TO DIMINISH BELOW CRITERIA ACROSS OUR SOUTHERN OUTER-
WATERS.
THE OTHER CONCERN FOR MARINERS WILL BE FOR AREAS OF FOG DEVELOPING
TODAY AND PERSISTING INTO TONIGHT ACROSS THE SOUTHERN WATERS AS HIGH
DEWPOINT AIR ADVECTS IN OVER THE RELATIVELY COLD OCEAN.
OUTLOOK /TUESDAY NIGHT THROUGH FRIDAY/...
TUESDAY NIGHT: WINDS LESS THAN 25 KT. AREAS OF SEAS APPROACHING
5 FT. SLIGHT CHANCE OF RAIN SHOWERS.
WEDNESDAY: WINDS LESS THAN 25 KT. SEAS LOCALLY APPROACHING
5 FT. SLIGHT CHANCE OF RAIN SHOWERS.
WEDNESDAY NIGHT: WINDS LESS THAN 25 KT. AREAS OF SEAS
APPROACHING 5 FT. CHANCE OF RAIN SHOWERS.
THURSDAY THROUGH THURSDAY NIGHT: WINDS LESS THAN 25 KT. AREAS
OF SEAS APPROACHING 5 FT. SLIGHT CHANCE OF RAIN SHOWERS.
FRIDAY: WINDS LESS THAN 25 KT. SEAS LOCALLY APPROACHING 5 FT.
SLIGHT CHANCE OF RAIN SHOWERS.
BOX WATCHES/WARNINGS/ADVISORIES
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ230-
236.
GALE WARNING UNTIL 6 PM EDT THIS EVENING FOR ANZ231>234.
SMALL CRAFT ADVISORY UNTIL 5 AM EDT TUESDAY FOR ANZ235-237.
SMALL CRAFT ADVISORY UNTIL 2 AM EDT TUESDAY FOR ANZ250-251.
SMALL CRAFT ADVISORY UNTIL NOON EDT TUESDAY FOR ANZ254>256.
DISCUSSION...FRANK
AVIATION...FRANK
MARINE...FRANK
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