542
FXUS61 KBOX 121753
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
153 PM EDT WED AUG 12 2026
WHAT HAS CHANGED
LATER FRONTAL PASSAGE FRIDAY BRINGS INCREASED SHOWER AND
THUNDERSTORM POTENTIAL.
KEY MESSAGES
- A GENERALLY UNSETTLED PATTERN PERSISTS THROUGH FRIDAY AS A
QUASI-STATIONARY FRONT REMAINS ACROSS THE NORTHEAST,
RESULTING IN MULTIPLE OPPORTUNITIES FOR SHOWERS AND
THUNDERSTORMS. WHILE COVERAGE SHOULD REMAIN LIMITED THROUGH
THURSDAY, STRONGER FORCING FRIDAY MAY BRING A BETTER CHANCE
FOR SHOWERS AND THUNDERSTORMS BEFORE DRIER WEATHER ARRIVES FOR
THE WEEKEND.
- TEMPERATURES TREND TOWARD SEASONABLE LEVELS THROUGH THE END OF
THE WEEK, WITH LOWER HUMIDITY AND MORE COMFORTABLE CONDITIONS
EXPECTED THIS WEEKEND.
DISCUSSION
KEY MESSAGE 1...A GENERALLY UNSETTLED PATTERN PERSISTS THROUGH
FRIDAY AS A QUASI-STATIONARY FRONT REMAINS ACROSS THE NORTHEAST,
RESULTING IN MULTIPLE OPPORTUNITIES FOR SHOWERS AND THUNDERSTORMS.
WHILE COVERAGE SHOULD REMAIN LIMITED THROUGH THURSDAY, STRONGER
FORCING FRIDAY MAY BRING A BETTER CHANCE FOR SHOWERS AND
THUNDERSTORMS BEFORE DRIER WEATHER ARRIVES FOR THE WEEKEND.
A MID-LEVEL RIDGE REMAINS ANCHORED ACROSS THE SOUTH-CENTRAL AND
SOUTHEASTERN CONUS, WHILE A WEAKER RIDGE EXTENDS INTO THE CANADIAN
PRAIRIES. THIS LEAVES THE FLOW ALOFT RELATIVELY QUASI-ZONAL,
ALLOWING SHORTWAVE ENERGY TO QUICKLY TRAVERSE THE CONTINENT INTO THE
NORTHEAST. GIVEN THE LACK OF STRONG SYNOPTIC-SCALE FORCING, SHOWER
DEVELOPMENT AND COVERAGE WILL REMAIN DIFFICULT TO PIN DOWN THROUGH
THURSDAY.
TODAY WILL BE MAINLY DRY, WITH A WEAK SURFACE LOW PASSING SOUTH OF
NEW ENGLAND. THE HIGHEST POPS, GENERALLY 10-20 PERCENT, WILL BE
CONFINED TO THE IMMEDIATE SOUTH COAST AND ISLANDS DURING THE
MORNING. OTHERWISE, A MIX OF SUN AND CLOUDS IS EXPECTED, ALTHOUGH
ANOTHER SURGE OF WILDFIRE SMOKE MAY RESULT IN HAZY OR MILKY SKIES. A
MID-LEVEL SHORTWAVE TROUGH WILL MOVE THROUGH TONIGHT INTO THURSDAY
MORNING, PROVIDING ENOUGH FORCING FOR SCATTERED SHOWERS AND A FEW
THUNDERSTORMS. COVERAGE SHOULD REMAIN LIMITED, HOWEVER, WITH POPS
GENERALLY IN THE 20-30 PERCENT RANGE NORTHWEST OF I-95 AND I-495.
THURSDAY FEATURES A WEAK DISTURBANCE PASSING THROUGH THE FLOW, WITH
SIMILAR POPS ONCE AGAIN ACROSS THE EASTERN HALF OF SOUTHERN NEW
ENGLAND.
A MORE NOTABLE CHANGE ARRIVES FRIDAY AS THE FRONT'S DEPARTURE HAS
TRENDED LATER. A STRONGER 500 MB SHORTWAVE TROUGH AND INCREASING
FORCING WILL BRING A BETTER CHANCE FOR SHOWERS AND THUNDERSTORMS,
PARTICULARLY AS THE FRONT FINALLY PUSHES OFFSHORE. BEHIND THE FRONT,
HIGH PRESSURE BUILDS INTO THE REGION FOR SATURDAY AND SUNDAY,
BRINGING A MUCH DRIER AIRMASS ALONG WITH MOSTLY SUNNY AND
COMFORTABLE CONDITIONS. THE NEXT OPPORTUNITY FOR MORE SUBSTANTIAL
RAINFALL ARRIVES LATE SUNDAY INTO MONDAY AS LOW PRESSURE APPROACHES
FROM THE NORTHERN GREAT LAKES.
KEY MESSAGE 2...TEMPERATURES TREND TOWARD SEASONABLE LEVELS THROUGH
THE END OF THE WEEK, WITH LOWER HUMIDITY AND MORE COMFORTABLE
CONDITIONS EXPECTED THIS WEEKEND.
TEMPERATURES ALOFT GRADUALLY COOL THROUGH THE END OF THE WEEK, WITH
DEW POINTS FOLLOWING SUIT. THE RESULT WILL BE A NOTICEABLY COOLER
AND MORE REFRESHING AIRMASS BY LATE WEEK. THE WEEKEND IS SHAPING UP
TO BE THE MOST COMFORTABLE STRETCH OF WEATHER IN QUITE SOME TIME,
WITH HIGHS GENERALLY IN THE UPPER 70S ACROSS INTERIOR SOUTHERN NEW
ENGLAND AND LOWER 80S ALONG THE COASTAL PLAIN. DEW POINTS IN THE 50S
WILL MAKE FOR MUCH MORE COMFORTABLE CONDITIONS, WHILE OVERNIGHT LOWS
FALL INTO THE 50S SATURDAY AND SUNDAY MORNINGS. TEMPERATURES EARLY
NEXT WEEK REMAIN SEASONABLE, THOUGH DEW POINTS MAY TREND UPWARD ON
MONDAY DEPENDING ON THE TIMING OF THE NEXT FRONTAL SYSTEM.
AVIATION /18Z WEDNESDAY THROUGH MONDAY/
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
18Z TAF UPDATE:
THROUGH 00Z THURSDAY: HIGH CONFIDENCE.
VFR. SHRA/ROGUE TS DEVELOPING IN VT/NH MAKES A CLOSE PASS ESE
BUT SHOULD END NORTH OF TAFS THROUGH 00Z. N/NE WINDS UNDER 10
KT, WITH SEABREEZES AT BOS.
TONIGHT: HIGH CONFIDENCE OVERALL BUT MODERATE CONFIDENCE ON
TIMING.
VFR INITIALLY, BUT SHRA/EMBEDDED WEAK TS COMING IN FROM THE NW
AFTER 03Z WILL DETERIORATE CONDITIONS INTO THE VFR/MVFR RANGE.
BKN/OVC VFR/MVFR CEILINGS WITH SHRA MORE LIKELY FOR BDL, BUT
HAVE LEFT AS PROB30S AFTER 06Z FOR BOS, PVD AND ORH AND THE CAPE
AIRPORTS. WINDS BECOME SW 5-10 KT.
THURSDAY: MODERATE CONFIDENCE.
LINGERING SHRA/PSBL TS MAINLY PVD AND CAPE AIRPORTS SHOULD MOVE
OFFSHORE BY 14Z. LEFTOVER SCT/BKN VFR/MVFR DECKS SHOULD BEGIN TO
SCATTER OUT BY 15-17Z, WHICH WILL INCREASE THE RISK FOR SHRA/TS
MAINLY FROM THE MASS PIKE NORTH AS SFC COLD FRONT MOVES THROUGH.
COVERAGE LOOKS TOO SPOTTY FOR A TAF MENTION BUT WILL NEED TO BE
CONSIDERED IN LATER TAF ISSUANCES. WINDS SW TO W UNDER 10 KT,
THEN SHIFT TO WNW/NW 5-10K KT AFTER 20Z.
THURSDAY NIGHT: HIGH CONFIDENCE.
SHRA DISSIPATES EARLY TO VFR. NW WINDS 5-10 KT.
KBOS TERMINAL...HIGH CONFIDENCE.
KBDL TERMINAL...HIGH CONFIDENCE.
OUTLOOK /THURSDAY NIGHT THROUGH MONDAY/...
THURSDAY NIGHT: VFR. SLIGHT CHANCE SHRA.
FRIDAY THROUGH FRIDAY NIGHT: VFR. BREEZY.
SATURDAY THROUGH SATURDAY NIGHT: VFR.
SUNDAY: MAINLY VFR, WITH LOCAL IFR POSSIBLE. BREEZY. SLIGHT
CHANCE SHRA.
MARINE
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
THROUGH THURSDAY NIGHT: HIGH CONFIDENCE.
SUB-SCA WINDS AND SEAS THROUGH THE PERIOD. N WINDS UNDER 10 KT
SHIFT TO SW EARLY TONIGHT AROUND 10-15 KT, THEN REMAIN SO UNTIL
FRONTAL PASSAGE LATE THURS/EARLY THURS NIGHT WITH WINDSHIFT TO
NW AROUND 10-15 KT. SEAS 3 FT OR LESS ALL WATERS. POSSIBLE
THUNDERSTORMS OVER MAINLY SOUTHERN WATERS OVERNIGHT TONIGHT,
THEN MORE ISOLATED SHRA THURS AFTERNOON OVER NORTHEAST WATERS.
OUTLOOK /THURSDAY NIGHT THROUGH MONDAY/...
THURSDAY NIGHT: WINDS LESS THAN 25 KT. SLIGHT CHANCE OF RAIN
SHOWERS.
FRIDAY: WINDS LESS THAN 25 KT. SEAS LOCALLY APPROACHING 5 FT.
SLIGHT CHANCE OF RAIN SHOWERS.
FRIDAY NIGHT THROUGH SATURDAY: WINDS LESS THAN 25 KT. AREAS OF
SEAS APPROACHING 5 FT.
SATURDAY NIGHT THROUGH SUNDAY: WINDS LESS THAN 25 KT.
BOX WATCHES/WARNINGS/ADVISORIES
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.
DISCUSSION...DOOLEY
AVIATION...BELK/LOCONTO
MARINE...BELK/LOCONTO
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