057
FXUS61 KBOX 092330
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
730 PM EDT SAT AUG 9 2025
SYNOPSIS
HIGH PRESSURE WILL BRING A COMFORTABLY COOL NIGHT TONIGHT. VERY
WARM TO HOT WEATHER RETURNS SUNDAY WITH POTENTIAL FOR 90 DEGREE
HEAT IN THE INTERIOR. MORE WIDESPREAD HEAT AND MODERATE
HUMIDITY THEN TAKES HOLD THROUGH WEDNESDAY. THIS MAY CONTINUE
INTO THURSDAY BEFORE TEMPERATURES COOL A BIT BY FRIDAY. DRY
WEATHER IS EXPECTED THROUGH WEDNESDAY BEFORE THE CHANCE FOR SOME
SHOWERS AND THUNDERSTORMS RETURNS TOWARDS THE END OF THE WEEK.
NEAR TERM /UNTIL 6 AM SUNDAY MORNING/
KEY MESSAGES:
* WARM AND DRY THIS AFTERNOON
* ONE MORE COOL AND COMFORTABLE NIGHT
MESOANALYSIS SHOWS AXIS OF SURFACE HIGH PRESSURE DIRECTLY OVER
SOUTHERN NEW ENGLAND THIS AFTERNOON. SURFACE OBSERVATIONS SHOW A
PLEASANT START TO THE WEEKEND UNFOLDING WITH MOST AREAS QUICKLY
WARMING INTO THE UPPER 70S AND LOW 80S. IT'S A RATHER COMFORTABLE
DAY AS WELL AS DEWPOINTS FALL INTO THE LOW 50S WITH A WELL-MIXED AND
DRY BOUNDARY LAYER. EXPECTING WARMING TO CONTINUE FOR THE REST OF
THE AFTERNOON WITH SOME INTERIOR LOCATIONS POSSIBLY APPROACHING THE
UPPER 80S AND PERHAPS 90 DEGREES.
ANOTHER CLEAR NIGHT FOR MOST OF US WILL ALLOW FOR EFFICIENT
RADIATIONAL COOLING, ESPECIALLY ACROSS THE INTERIOR. EXPECTING
INCREASING DEWPOINTS ACROSS COASTAL AREAS AND SOUTHEAST
MASSACHUSETTS AS A WEAK SOUTHWESTERLY RETURN FLOW BECOMES
ESTABLISHED. HIGH-RES GUIDANCE IS SHOWING A CHANCE FOR PATCHY FOG
ACROSS SOUTHEAST MASS AND SOUTHERN RHODE ISLAND BY EARLY SUNDAY
MORNING AS DEWPOINTS INCREASE.
SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/
KEY MESSAGES:
* WARMER AND BECOMING A BIT MORE HUMID SUNDAY
THE HIGH PRES SHIFTS OFFSHORE AS AN UPPER RIDGE BUILDS OVER NEW ENG.
WARMING TEMPS ALOFT WITH 850 MB TEMPS REACHING 16-17C WILL RESULT IN
HIGHS WELL INTO THE 80S WITH SOME LOWER 90S IN THE CT VALLEY AND
INTERIOR NE MA SUNDAY AFTERNOON. IT WILL BECOME A BIT MORE HUMID AS
HIGHER PWATS MOVES INTO THE REGION, BUT WELL SHORT OF OPPRESSIVE
LEVELS WITH DEWPOINTS INTO THE LOWER 60S.
LONG TERM /MONDAY THROUGH SATURDAY/
KEY MESSAGES:
* MULTI-DAY STRETCH OF HEAT WITH MODERATE HUMIDITY THROUGH
WEDNESDAY. HEAT MAY CONTINUE INTO THURSDAY, BUT CONFIDENCE REMAINS
LOW.
* COOLER TEMPERATURES MOVE IN FRIDAY HEADING INTO THE WEEKEND
* CHANCE FOR SOME SHOWERS AND T-STORMS TOWARD THE END OF NEXT WEEK.
OTHERWISE, A DRY PATTERN OVERALL.
AN UPPER LEVEL RIDGE BUILDS IN OVER NEW ENGLAND TO START THE WEEK
AND IS EXPECTED TO BE THE DOMINATING FORCE THROUGH MIDWEEK. 925 MB
TEMPERATURES SIT AROUND 25C WITH 850 MB TEMPERATURES UP TO 20C FOR
TUESDAY AND WEDNESDAY AFTERNOON. THESE WARMER TEMPERATURES ALOFT
DROP OFF AS THE RIDGE BEGINS TO BREAK DOWN HEADING INTO THURSDAY,
DROPPING UPPER LEVEL TEMPS BY AROUND 5C. HIGHS THURSDAY MAY STILL
SIT IN THE UPPER 80S AND LOW 90S, BUT AFTER THAT THEY DROP INTO THE
LOW 80S HEADING INTO THE WEEKEND.
COMPARED TO PREVIOUS HOT STRETCHES FROM THIS SUMMER, DEW POINTS ARE
NOT EXPECTED TO BE AS HIGH, MIXING OUT INTO THE LOW TO MID-60S.
ENSEMBLE PROBS STILL INDICATE CHANCES FOR HEAT INDICES TO REACH THE
MID-90S MONDAY THROUGH WEDNESDAY, PARTICULARLY IN THE MERRIMACK AND
CT RIVER VALLEYS, SO FUTURE HEAT ADVISORIES CANNOT BE COMPLETELY
RULED OUT.
A FRONTAL BOUNDARY MOVES THROUGH THE REGION SOMETIME THURSDAY AND
POSSIBLY INTO FRIDAY, BRINGING THE CHANCE FOR SOME RAIN WITH IT.
THERE IS STILL SIGNIFICANT SPREAD ACROSS THE ENSEMBLES AND
DETERMINISTIC MODELS REGARDING RAINFALL, SO TIMING AND LOCATION
REMAIN UNCERTAIN AT THIS TIME. ASIDE FROM THESE LOW CHANCES, THE
OVERALL PATTERN REMAINS DRY AND WARM.
AVIATION /00Z SUNDAY THROUGH THURSDAY/
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
00Z TAF UPDATE:
TONIGHT...MODERATE CONFIDENCE.
VFR WITH PATCHY MVFR/IFR FOG POSSIBLE ACROSS SE MA INTO THE
CAPE. SOME MVFR/IFR FOG ALSO POSSIBLE FOR THE ISLANDS. LIGHT
AND VARIABLE WINDS.
SUNDAY...HIGH CONFIDENCE.
VFR. LOCAL SEABREEZES MOVING IN BY MID-MORNING. AWAY FROM THE
COASTS, WINDS GENERALLY S TO SW TOMORROW UP TO 10 KTS.
SUNDAY NIGHT...MODERATE CONFIDENCE.
VFR WITH ISOLATED MVFR/IFR POSSIBLE IN THE VALLEYS, SE MA, AND
THE CAPE AND ISLANDS DUE TO FOG. WINDS SHIFTING SW AND BECOMING
LIGHT TO CALM, ESPECIALLY IN THE INTERIOR.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK /MONDAY THROUGH THURSDAY/...
MONDAY THROUGH TUESDAY NIGHT: VFR.
WEDNESDAY: VFR. BREEZY.
WEDNESDAY NIGHT THROUGH THURSDAY: VFR. BREEZY. SLIGHT CHANCE
SHRA.
MARINE
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MEDIUM - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
THROUGH SUNDAY NIGHT...HIGH CONFIDENCE.
TRANQUIL BOATING CONDITIONS EXPECTED TO CONTINUE WITH E-SE WINDS 15
KT OR LESS BECOMING S DURING SUNDAY, THEN SW SUNDAY NIGHT. SEAS 3 FT
OR LESS ALL WATERS.
OUTLOOK /MONDAY THROUGH THURSDAY/...
MONDAY THROUGH MONDAY NIGHT: WINDS LESS THAN 25 KT. SEAS
LOCALLY APPROACHING 5 FT.
TUESDAY THROUGH THURSDAY: WINDS LESS THAN 25 KT.
BOX WATCHES/WARNINGS/ADVISORIES
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.
SYNOPSIS...HRENCECIN/FT
NEAR TERM...FT
SHORT TERM...FT
LONG TERM...HRENCECIN
AVIATION...HRENCECIN/FT
MARINE...HRENCECIN/FT
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page