526
FXUS61 KBOX 241935
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
335 PM EDT TUE JUN 24 2025
SYNOPSIS
EXTREME HEAT PEAKS TODAY, THOUGH WEDNESDAY WILL BE SLIGHTLY
COOLER, IT WILL STILL BE VERY WARM AND HUMID. SCATTERED
THUNDERSTORMS ARE POSSIBLE WEDNESDAY AFTERNOON, ESPECIALLY SOUTH
OF THE MASS PIKE, AS A COLD FRONT MOVES FROM NORTH TO SOUTH
ACROSS THE REGION. FINALLY TURNING COOLER THURSDAY THROUGH THE
UPCOMING WEEKEND WITH DAILY CHANCES OF SHOWERS AND
THUNDERSTORMS.
NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/
KEY MESSAGES:
* EXTREME HEAT WARNING EXPIRES AT 8PM.
* VERY LITTLE HEAT RELIEF OVERNIGHT.
DAILY HIGH TEMPERATURE RECORDS HAVE BEEN SHATTERED ACROSS
SOUTHERN NEW ENGLAND, WITH MONTHLY RECORDS BROKEN IN BOTH BOSTON
AND PROVIDENCE. EXTREME HEAT WARNINGS ARE STILL IN EFFECT
THROUGH 8PM TONIGHT, BUT VERY LITTLE RELIEF IS EXPECTED
OVERNIGHT WITH TEMPS REMAINING IN THE MID TO UPPER 70S. AN AIR
QUALITY ALERT REMAINS IN EFFECT THROUGH 11PM IN COLLABORATION
WITH MASSACHUSETTS DEPARTMENT OF ENVIRONMENTAL PROTECTION AND
RHODE ISLAND DEPARTMENT OF ENVIRONMENTAL MANAGEMENT FOR GROUND
LEVEL OZONE CONCENTRATIONS TO APPROACH OR EXCEED UNHEALTHY
STANDARDS.
CONTINUE TO STAY HYDRATED, WEAR LIGHT WEIGHT AND LIGHT COLORED
CLOTHING, SEEK OUT AIR-CONDITIONED ROOMS, AND LIMIT STRENUOUS
ACTIVITY.
SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/
KEY MESSAGES:
* HEAT ADVISORY FOR MOST OF SOUTHERN NEW ENGLAND THROUGH 7PM
WEDNESDAY.
* SCATTERED THUNDERSTORMS POSSIBLE WEDNESDAY AFTERNOON.
EXTREME HEAT WARNINGS GIVE WAY TO HEAT ADVISORIES THIS EVENING.
WEDNESDAY IS EXPECTED TO BE A LITTLE COOLER, BUT NOT MUCH.
DAYTIME TEMPERATURES WILL ONCE AGAIN SKYROCKET AS SOON AS THE
SUN COMES UP, AND DEWPOINTS IN THE UPPER 60S TO LOW 70S WILL
MAKE THE APPARENT TEMPS JUMP TO THE UPPER 90S, POSSIBLY EVEN 100
IN THE CT VALLEY AND NORTHERN RI.
A COLD FRONT MOVING INTO SOUTHERN NEW ENGLAND FROM THE NORTH
WILL BRING CHANCES FOR SCATTERED THUNDERSTORMS WEDNESDAY
AFTERNOON. BETWEEN THE COLD FRONT, PRE-FRONTAL TROUGH AND SEA
BREEZES, THERE WILL LIKELY BE ENOUGH FORCING TO GET SOME
CONVECTION GOING SOUTH OF THE MASS PIKE AND INTO NORTHERN RI.
WITH GUIDANCE INDICATED CAPE AROUND 1000 J/KG, SOME STORMS COULD
BECOME STRONG TO SEVERE, BUT THE CHANCE IS ON THE LOWER END.
COOLER AIR MOVES INTO PLACE POST-FROPA AND FINALLY BRINGS SOME
RELIEF FROM THE HEAT WEDNESDAY NIGHT, WITH TEMPS IN THE MID TO
UPPER 60S.
LONG TERM /THURSDAY THROUGH TUESDAY/
* SIGNIFICANT COOL DOWN COMING THURSDAY INTO THE WEEKEND BEFORE
TEMPS RETURN TO THE UPPER 80S AND LOW 90S EARLY NEXT WEEK.
* DAILY CHANCES OF RAIN AND POSSIBLY SOME THUNDERSTORMS EACH DAY
BUT DIFFICULT TO TIME OUT AT THIS POINT.
RELIEF FROM THE HEAT COMES THURSDAY AS THE RIDGE IS FLATTENED
AND SURFACE HIGH PRESSURE EXPANDS SOUTH FROM CANADA. THIS
DIRECTS COOL NORTHEAST/ONSHORE FLOW OFF THE ATLANTIC OVER
SOUTHERN NEW ENGLAND. TOGETHER THIS WILL LEAD TO HIGH
TEMPERATURES ABOUT 30 DEGREES COLDER THAN TODAY (TUESDAY). IN
FACT, HIGH TEMPERATURES IN THE 70S WILL PUT US BELOW AVERAGE FOR
LATE JUNE. BY SUNDAY INTO MONDAY THAT FLOW ONCE AGAIN TURNS
SOUTHWEST AS A TROUGH OF LOW PRESSURE MOVES INTO THE GREAT LAKES
ADVECTING WARMER AIR NORTH, PUSHING HIGHS BACK INTO THE 80S AND
LOW 90S.
PRECIPITATION-WISE WE'LL SEE PERIODS OF MARGINALLY UNSETTLED
WEATHER THANKS TO ZONAL FLOW WITH SEVERAL WEAK DISTURBANCES
MOVING THROUGH BETWEEN THURSDAY AND EARLY NEXT WEEK. LACKING ANY
LARGE SCALE FORCING, JUST WEAK MID LEVEL SHORTWAVES AND SURFACE
BOUNDARIES, NOT LOOKING AT MUCH IN THE WAY OF WIDESPREAD HEAVY
RAINFALL, BUT PERIODS OF SHOWERS AND THUNDERSTORMS POSSIBLE
THROUGH THE WEEKEND. AT THIS POINT, UNFORTUNATELY THE MOST
POTENT SHORTWAVE AND STRONGEST FORCING FOR ASCENT LOOKS TO PASS
AROUND SATURDAY; THIS IS WHERE WE'VE INDICATED THE BEST CHANCE
FOR SHOWERS.
AVIATION /20Z TUESDAY THROUGH SUNDAY/
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT. MODERATE - 30 TO 60 PERCENT. HIGH -
GREATER THAN 60 PERCENT.
18Z UPDATE:
TONIGHT: HIGH CONFIDENCE.
VFR. W WINDS AROUND 10 KTS WITH GUSTS UP TO 20 KTS POSSIBLE
ACROSS THE INTERIOR TERMINALS.
WEDNESDAY AND WEDNESDAY NIGHT: MODERATE CONFIDENCE.
VFR. SCATTERED EARLY TO MID AFTERNOON SHOWERS AND
THUNDERSTORMS. A FEW SHOWERS LINGER ACROSS THE ISLANDS AND CAPE
COD OVERNIGHT. LIGHT AND VARIABLE WINDS DEPENDING ON PLACEMENT
OF THE COLD FRONT. BECOMING NORTHEAST WEDNESDAY NIGHT.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF. SOME GUSTS UP TO 20 KTS
POSSIBLE. SOME CHANCE OF SHOWERS IN THE AREA TOMORROW
AFTERNOON, BUT NOT CONFIDENT ENOUGH TO INCLUDE IN TAF.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF. VFR. HAZY CONDITIONS
POSSIBLE GIVEN HOT AND HUMID WEATHER. SOME CHANCE OF SHOWERS IN
THE AREA TOMORROW AFTERNOON, BUT NOT CONFIDENT ENOUGH TO INCLUDE
IN TAF.
OUTLOOK /THURSDAY THROUGH SUNDAY/...
THURSDAY: VFR. BREEZY. SLIGHT CHANCE SHRA.
THURSDAY NIGHT: VFR. CHANCE SHRA.
FRIDAY: MAINLY VFR, WITH LOCAL MVFR POSSIBLE. BREEZY. SLIGHT
CHANCE SHRA.
FRIDAY NIGHT: MAINLY VFR, WITH LOCAL IFR POSSIBLE. BREEZY.
CHANCE SHRA, SLIGHT CHANCE TSRA.
SATURDAY: MVFR/IFR CONDITIONS POSSIBLE. BREEZY. CHANCE SHRA,
CHANCE TSRA.
SATURDAY NIGHT: MAINLY VFR, WITH LOCAL IFR POSSIBLE. CHANCE
SHRA, SLIGHT CHANCE TSRA.
SUNDAY: SLIGHT CHANCE SHRA, SLIGHT CHANCE TSRA.
MARINE
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT. MEDIUM - 30 TO 60 PERCENT. HIGH -
GREATER THAN 60 PERCENT.
TODAY THROUGH WEDNESDAY: HIGH CONFIDENCE.
SOUTHWEST WINDS OF 10 TO 15 KNOTS GUSTING UP TO 20 KNOTS OVER
THE SOUTHERN WATERS. SEAS REMAIN LESS THAN 2 FEET.
WEAK COLD FRONT APPROACHES FROM THE NORTH ON WEDNESDAY,
INCREASING CLOUDS AND A FEW POP-UP SHOWERS AND THUNDERSTORMS.
NORTHERN WATERS HAVE NORTHERLY WINDS WHILE THE SOUTHERLY WATERS
HAVE A SOUTHERLY WIND. WIND BECOMES NORTHEAST FOR ALL WATERS
WEDNESDAY NIGHT AND INCREASE TO 10 TO 15 KNOTS. SEAS ARE LESS
THAN 2 FEET.
OUTLOOK /THURSDAY THROUGH SUNDAY/...
THURSDAY: WINDS LESS THAN 25 KT. SLIGHT CHANCE OF RAIN SHOWERS.
THURSDAY NIGHT: WINDS LESS THAN 25 KT. CHANCE OF RAIN SHOWERS.
FRIDAY: WINDS LESS THAN 25 KT. SEAS LOCALLY APPROACHING 5 FT.
SLIGHT CHANCE OF RAIN SHOWERS.
FRIDAY NIGHT: WINDS LESS THAN 25 KT. SEAS LOCALLY APPROACHING 5
FT. CHANCE OF RAIN SHOWERS, SLIGHT CHANCE OF THUNDERSTORMS.
SATURDAY THROUGH SATURDAY NIGHT: WINDS LESS THAN 25 KT. SEAS UP
TO 5 FT. CHANCE OF RAIN SHOWERS, SLIGHT CHANCE OF
THUNDERSTORMS.
SUNDAY: WINDS LESS THAN 25 KT. AREAS OF SEAS APPROACHING 5 FT.
SLIGHT CHANCE OF RAIN SHOWERS.
BOX WATCHES/WARNINGS/ADVISORIES
CT...EXTREME HEAT WARNING UNTIL 8 PM EDT THIS EVENING FOR
CTZ002>004.
HEAT ADVISORY FROM 8 PM THIS EVENING TO 7 PM EDT WEDNESDAY FOR
CTZ002>004.
MA...EXTREME HEAT WARNING UNTIL 8 PM EDT THIS EVENING FOR
MAZ003>007-010>021-026.
HEAT ADVISORY FROM 8 PM THIS EVENING TO 7 PM EDT WEDNESDAY FOR
MAZ003-005-010>014-017-018-020-021-026.
HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR MAZ002-008-009-
022.
AIR QUALITY ALERT UNTIL 11 PM EDT THIS EVENING FOR MAZ017>024.
RI...EXTREME HEAT WARNING UNTIL 8 PM EDT THIS EVENING FOR
RIZ001>007.
HEAT ADVISORY FROM 8 PM THIS EVENING TO 7 PM EDT WEDNESDAY FOR
RIZ001>007.
AIR QUALITY ALERT UNTIL 11 PM EDT THIS EVENING FOR RIZ001>008.
AIR QUALITY ALERT FROM 11 AM TO 11 PM EDT WEDNESDAY FOR
RIZ006>008.
MARINE...NONE.
SYNOPSIS...BW/MCMINN
NEAR TERM...MCMINN
SHORT TERM...MCMINN
LONG TERM...BW
AVIATION...MCMINN
MARINE...MCMINN
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