466
FXUS61 KBOX 141841
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
241 PM EDT THU AUG 14 2025
SYNOPSIS
SCATTERED SHOWERS AND THUNDERSTORMS AGAIN TODAY ALONG WITH A
LOW RISK FOR SOME URBAN FLASH FLOODING. SEASONABLE TEMPERATURES
AND LOWER HUMIDITY LEVELS ARE EXPECTED FOR FRIDAY AND SATURDAY,
ALTHOUGH TEMPERATURES BRIEFLY WARM UP AGAIN FOR SUNDAY. AFTER
MIDWEEK, OUR NEXT CHANCE FOR RAIN IS WITH A COLD FRONT WHICH
LOOKS TO MOVE IN ON MONDAY.
NEAR TERM /THROUGH TONIGHT/
KEY MESSAGES...
* SCATTERED SHOWERS AND THUNDERSTORMS POSSIBLE THIS AFTERNOON
AND EVENING, SOME OF WHICH COULD LEAD TO LOCALIZED URBAN FLASH
FLOODING.
THE SURFACE LOW SLOWLY MOVING OFFSHORE HAS DRAPED A STALLED
COLD FRONT ACROSS SOUTHERN NEW ENGLAND WHICH WILL FINALLY PUSH
OUT LATER TONIGHT. OVER SOUTHEAST MA AND RI, AHEAD OF THE FRONT,
A PLUME OF ANOMOLOUSLY DEEP MOISTURE SITS WITH PWATS NEAR 2
INCHES. THIS, TOGETHER WITH TALL-SKINNY CAPE PROFILES, DEEP WARM
CLOUD DEPTHS, AND SLOW STORM MOTION WILL MEAN A RISK OF SOME
STORMS BRINGING HEAVY DOWNPOURS THAT COULD LEAD TO LOCALIZED
FLASH FLOODING. THE GREATEST RISK WILL REMAIN AHEAD OF THE
FRONT, OVER THE SOUTH COAST AND SOUTHERN RI, AS A SWATH OF DRY
AIR IS QUICKLY MOVING INTO WESTERN MA BEHIND THE FRONT. WILL
LIKELY SEE A FEW QUICK POP-UPS IN WESTERN MA AND/OR NORTHERN RI,
BUT THEY SHOULD BE VERY BRIEF. ANY FLOODING ISSUES ARE EXPECTED
TO BE ISOLATED AS OPPOSED TO WIDESPREAD. WE CONTINUE TO CARRY
THE MARGINAL RISK (LEVEL 1 OR 4) OF FLASH FLOODING. THE
POSITIVELY TROPICAL-FEELING AIRMASS CONTINUES FOR ONE MORE DAY
AS HIGHS REACH WELL INTO THE 80S WITH DEWPOINTS IN THE 70S.
DRIER AIR KICKS IN BEHIND THE FRONT LATER TONIGHT.
SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/
KEY MESSAGES...
* COOLER TEMPERATURES AND DRIER WEATHER KICK OFF THE WEEKEND.
FRIDAY STANDS TO BE MORE TOLERABLE TEMPERATURE-WISE. AFTERNOON
TEMPS WILL STILL BE IN THE LOW TO MID 80S, BUT DEWPOINTS WILL BE
SIGNIFICANTLY LOWER... IN THE UPPER 50S TO LOW 60S. THE DRY
AIRMASS MOVING IN BEHIND THE COLD FRONT WILL CLEAR OUT SKIES AND
BRING PLENTY OF SUNSHINE TO KICK OFF THE WEEKEND.
LONG TERM /SATURDAY THROUGH THURSDAY/
KEY MESSAGES:
* SEASONABLE TEMPERATURES WITH LOWER HUMIDITY LEVELS SAT
* WARMER AND MORE HUMID SUNDAY WITH CHANCES FOR
SHOWERS/THUNDERSTORMS IN AFTERNOON/EVENING.
* COOLER NEXT WEEK WITH POTENTIAL FOR SOME SCATTERED SHOWERS
TUES- THURS IN SPOTS.
SATURDAY:
SURFACE PRESSURE PERSISTS OVER SOUTHERN NEW ENGLAND SATURDAY
KEEPING CONDITIONS DRY WITH SEASONABLE TEMPERATURES. HIGHS
TEMPERATURES SHOULD RANGE IN THE LOW TO MID 80S. WEAK PRESSURE
GRADIENT AND HIGH PRESSURE CENTER IN THE EAST WILL SUPPORT
EASTERLY COMPONENT WINDS/LOCALIZED SEA BREEZES ALONG THE EAST
COASTLINE. THIS WILL KEEP THE COASTAL AREAS A BIT COOLER IN THE
MID-UPPER 70S.
SUNDAY:
A SHORTWAVE TROUGH IN THE MID-LEVEL FLOW ALOFT MOVES THROUGH ON
SUNDAY WITH AN ACCOMPANYING COLD FRONT. SURFACE WINDS TURN MORE
SOUTHWESTERLY WITH BRIEF ADVECTION OF HIGHER MOISTURE/DEWPOINT
AIR INTO SOUTHERN NEW ENGLAND. WEAK WARM ADVECTION WILL BRING
TEMPERATURES INTO THE MID-UPPER 80S WITH ELEVATED HUMIDITY
LEVELS MAKING IT FEEL LIKE LOW 90S. DAYTIME HEATING, MOISTURE,
AND AN APPROACHING FRONT/SHORTWAVE SHOULD SUPPORT DEVELOPMENT OF
AFTERNOON SHOWERS AND THUNDERSTORMS. DETERMINISTIC AND ENSEMBLE
GUIDANCE SHOW AT LEAST MARGINAL INSTABILITY IN PLACE WITH SOME
UNCERTAINTY ON HOW FAR EAST THE INSTABILITY AXIS EXTENDS INTO
SOUTHERN NEW ENGLAND. UPPER LEVEL FORCING APPEARS TO BE LIMITED
OVERALL, SO COVERAGE WILL BE MORE LIKELY SCATTERED IN NATURE.
OVERALL THERE WILL BE LOW CHANCES (25-40%) FOR AFTERNOON-EARLY
EVENING SHOWERS AND THUNDERSTORMS, WITH BETTER CHANCES FURTHER
WEST.
NEXT WEEK:
THE COLD FRONT WILL PUSH THROUGH THE REGION OVERNIGHT SUNDAY
INTO EARLY MONDAY BRINGING IN A COOL AIRMASS TO START THE WEEK.
ENSEMBLE GUIDANCE SHOWS THE AIRMASS TO BE BELOW NORMAL WITH
850MB TEMPERATURES 10-12C. THIS WILL BRING MUCH COOLER HIGHS IN
THE 70S, PERHAPS A FEW 80S IN THE CT VALLEY. FLOW ALOFT WILL BE
GENERALLY WEAK TROUGHING WITH A WEAK SHORTWAVE OR TWO MOVING
THROUGH DURING THE WEEK. THIS MAY BRING WEAK ISOLATED TO
SCATTERED SHOWERS. GIVEN FAIRLY WEAK FORCING AND UNCERTAINTY IN
TIMING OF THE WAVES THIS FAR OUT, TIMING OF PRECIPITATION IS LOW
CONFIDENCE STILL. ALTHOUGH THERE SEEMS TO BE CHUNKS OF MEMBERS
SHOWING HIGHER PROBABILITIES FOR SEEING SHOWERS
TUESDAY/WEDNESDAY AND POTENTIALLY INTO THURSDAY. CONFIDENCE
SHOULD INCREASE AS WE GET CLOSER, BUT OVERALL NOT EXPECTING ANY
SIGNIFICANT RAINFALL WITH THESE WEAKER SHORTWAVES.
STILL VERY FAR AWAY, BUT OVERALL ACTIVITY IN THE TROPICS HAS
SEEN AN UPTICK IN THE PAST FEW WEEKS. WE CONTINUE TO MONITOR FOR
IMPACTS FROM TROPICAL SYSTEM ERIN AS IT RECURVES N/NE'WARD (IN
SOME FASHION) LATE NEXT WEEK. AT THIS POINT, ANY IMPACT WILL BE
OFFSHORE (MARINE, RIP CURRENTS, SURF). AGAIN, THIS WILL CONTINUE
TO BE MONITORED AS WE GET CLOSER AND MORE CONFIDENT/DETAILED
INFORMATION WILL BECOME AVAILABLE.
AVIATION /19Z THURSDAY THROUGH TUESDAY/
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
18Z TAF UPDATE:
TODAY...MODERATE CONFIDENCE OVERALL. LOW CONFIDENCE IN
PLACEMENT/TIMING OF SHOWERS/STORMS.
SCATTERED SHOWERS AND T-STORMS ARE POSSIBLE AGAIN THIS
AFTERNOON AND EVENING. CONFIDENCE IS LOWER WITH RESPECT TO
TIMING AND CHANCES AS COVERAGE IS MORE SCATTERED IN NATURE.
LIGHTNING, BRIEF GUSTY WINDS/OUTFLOWS, AND HEAVY RAIN POSSIBLE
IN ANY STORMS.
TONIGHT...MODERATE CONFIDENCE.
VFR. A FEW LINGERING SHOWERS AND STORMS POSSIBLE EARLY IN THE
EVENING. VFR FOR MOST TERMINALS. POTENTIAL FOR LOW STRATUS AND
FOG/MIST FOR CAPE/ISLANDS TONIGHT.
FRIDAY...HIGH CONFIDENCE.
VFR. NE WINDS 5-10 KTS.
KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. LOWER CONFIDENCE IN
TSRA CHANCES TODAY, BUT WOULD LIKELY BE IN THE 20-23Z.
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF. COULD SEE SOME POP-
UP SHOWERS/T-STORMS THIS EVENING, BUT CONFIDENCE IS TOO LOW TO
MENTION IN TAF.
OUTLOOK /SATURDAY THROUGH TUESDAY/...
SATURDAY THROUGH SATURDAY NIGHT: VFR.
SUNDAY: VFR. BREEZY. SLIGHT CHANCE SHRA, SLIGHT CHANCE TSRA.
SUNDAY NIGHT THROUGH MONDAY: VFR. BREEZY. SLIGHT CHANCE SHRA.
MONDAY NIGHT: VFR. SLIGHT CHANCE SHRA.
TUESDAY: BREEZY. SLIGHT CHANCE SHRA.
MARINE
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MEDIUM - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
HIGH CONFIDENCE THROUGH THE PERIOD.
WINDS INCREASE OUT OF THE SOUTHWEST TO 10 TO 15 KNOTS THIS
AFTERNOON WITH A SLIGHT CHANCE FOR AN AFTERNOON/EVENING
THUNDERSTORM. STORMS SHOULD DIMINISH SHORTLY AFTER MOVING OUT
OVER THE WATERS IF THEY MAKE IT THAT FAR.
SEAS REMAIN IN THE 2-3 FOOT RANGE. A COLD FRONT WILL CROSS THE
COASTAL WATERS LATE TOMORROW AFTERNOON RESULTING IN A WIND SHIFT
TO THE NORTHWEST. OVERALL QUIET CONDITIONS OVER THE MARINE
ZONES FOR THE FORESEEABLE FUTURE.
OUTLOOK /SATURDAY THROUGH TUESDAY/...
SATURDAY THROUGH SATURDAY NIGHT: WINDS LESS THAN 25 KT.
SUNDAY: WINDS LESS THAN 25 KT. SLIGHT CHANCE OF RAIN SHOWERS.
SUNDAY NIGHT: LOW RISK FOR SMALL CRAFT ADVISORY WINDS WITH
GUSTS UP TO 25 KT. SEAS LOCALLY APPROACHING 5 FT. SLIGHT CHANCE
OF RAIN SHOWERS.
MONDAY: WINDS LESS THAN 25 KT. AREAS OF SEAS APPROACHING 5 FT.
SLIGHT CHANCE OF RAIN SHOWERS.
MONDAY NIGHT THROUGH TUESDAY: WINDS LESS THAN 25 KT. AREAS OF
SEAS APPROACHING 5 FT.
BOX WATCHES/WARNINGS/ADVISORIES
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.
SYNOPSIS...MCMINN/MENSCH
NEAR TERM...KJC/MCMINN
SHORT TERM...KJC/MCMINN
LONG TERM...MENSCH
AVIATION...KJC/MCMINN/MENSCH
MARINE...MCMINN
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