009  
FXUS61 KBOX 120018  
AFDBOX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE BOSTON/NORTON MA  
818 PM EDT FRI JUL 11 2025  
   
SYNOPSIS
 
 
DAILY CHANCES FOR SCATTERED SHOWERS AND THUNDERSTORMS CONTINUE  
SATURDAY. WARM AND HUMID THROUGH THE WEEKEND. STILL A RISK FOR  
WIDELY SCATTERED SHOWERS OR THUNDERSHOWERS ON SUNDAY BUT MAINLY  
DRY WEATHER PREVAILS THE VAST MAJORITY OF THE TIME. A BETTER  
CHANCE AT SHOWERS AND THUNDERSTORMS THEN EXISTS ON MONDAY AS A  
FRONTAL SYSTEM MOVES THROUGH. INCREASING HEAT AND HUMIDITY  
AROUND THE MIDDLE OF NEXT WEEK, WHICH THEN LOOKS TO BREAK  
AROUND FRIDAY AS A COLD FRONT BRINGS RISK FOR SHOWERS AND  
THUNDERSTORMS.  
 

 
   
NEAR TERM /UNTIL 6 AM SATURDAY MORNING/
 
 
KEY MESSAGES:  
 
* WARM AND HUMID WITH FOG AND LOW STRATUS DEVELOPING OVERNIGHT  
 
QUIET BUT WARM AND HUMID TONIGHT ACROSS THE REGION. FOG EXPECTED TO  
DEVELOP AND LINGER INTO THE MORNING HOURS BEFORE DRIER AIR OFFSHORE  
MOVES IN FROM THE SE WINDS. DEWPOINTS AND LOWS IN THE MID TO UPPER  
60S, ALONG WITH CONTINUED LIGHT SOUTHERLY WINDS.  
 

 
   
SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/
 
 
KEY MESSAGES:  
 
* WARM AND HUMID AGAIN  
 
* ISOLATED SHOWERS AND THUNDERSTORMS POSSIBLE IN PARTS OF THE  
INTERIOR SATURDAY AFTERNOON  
 
DETAILS...  
 
HIGH PRESSURE CONTINUES TO SIT OVER THE GULF OF MAINE, CONTINUING  
SOUTHERLY TO SOUTHEASTERLY ONSHORE FLOW THROUGH THE WEEKEND.  
SOME ISOLATED SHOWERS AND THUNDERSTORMS LOOK POSSIBLE ONCE MORE  
IN THE INTERIOR DURING THE AFTERNOON HOURS. HOWEVER, THE SEVERE  
RISK REMAINS QUITE LIMITED; SHEAR LOOKS WEAK AND MLCAPE VALUES  
WILL REACH JUST OVER 1000 J/KG. SOME LOCALLY HEAVY DOWNPOURS ARE  
LOOKING POSSIBLE, AS PWATS ARE EXPECTED TO BE AROUND 1.75" IN  
THE AFTERNOON. HIGHS ARE EXPECTED TO BE IN THE MID TO UPPER 80S  
FOR MOST, WITH THE UPPER 70S OUT ALONG THE CAPE AND ISLANDS.  
 
SE WINDS CONTINUE INTO SATURDAY NIGHT WITH FOG LIKELY REDEVELOPING  
AND LOWER STRATUS RETURNING. LOWS EXPECTED TO BE IN THE LOW TO  
MID 60S, WITH DEWPOINTS AROUND THAT RANGE AS WELL.  
 

 
   
LONG TERM /SUNDAY THROUGH FRIDAY/
 
 
KEY MESSAGES:  
 
* WIDELY SCATTERED SHOWERS/T-SHOWERS OVER THE DISTANT INTERIOR  
SOUTHERN NEW ENGLAND, BUT MAINLY DRY WEATHER PREVAILS SUNDAY.  
 
* BETTER CHANCE AT MORE WIDESPREAD SHOWERS/T-STORMS MONDAY, ALTHOUGH  
LOWER INSTABILITY VALUES SHOULD LIMIT POTENCY OF THESE  
SHOWERS/STORMS.  
 
* VERY WARM TO HOT DURING THE MIDDLE OF NEXT WEEK, WITH ELEVATED  
HEAT INDICES AROUND 95-100F.  
 
* COLD FRONT FRIDAY BRINGS A BREAK FROM THE HEAT AND HUMIDITY, BUT  
ALSO A RISK FOR THUNDERSTORMS.  
 
DETAILS:  
 
SUNDAY:  
 
SUNDAY OVERALL LOOKS TO HAVE A SIMILAR THEME WEATHER-WISE AS DOES  
SATURDAY, WITH MAINLY DRY WEATHER FOR MOST OF CENTRAL AND EASTERN  
PORTIONS OF SOUTHERN NEW ENGLAND IN A REGIME OF MODEST SOUTHEAST  
ONSHORE FLOW GOVERNED BY SFC HIGH PRESSURE NEAR THE CANADIAN  
MARITIMES. MEANWHILE A MODEST UPSLOPE FLOW AGAINST THE BERKSHIRES  
AND HILLS IN LITCHFIELD COUNTY ALONG WITH WEAK CONVECTIVE  
INSTABILITY STILL SEEMS CAPABLE OF PRODUCING POP-UP WIDELY  
SCATTERED SHOWERS/THUNDERSHOWERS. HOWEVER COMPARED TO SAT,  
PROGGED INSTABILITY VALUES IS LESS, SO THE COVERAGE OF SHOWERS  
AND STORMS INTO WESTERN MA AND CT SHOULD PROVE LESS AND ALSO  
GENERALLY LESS POTENT. WILL LIKELY ALSO SEE ANOTHER RISK FOR  
OVERNIGHT PATCHY RADIATION FOG AND STRATUS AS WELL. HIGHS IN THE  
MID 80S (MID/UPPER 70S CAPE AND ISLANDS WITH ONSHORE FLOW, WITH  
MID/UPPER 80S FOR INTERIOR SOUTHERN NEW ENGLAND.  
 
MONDAY:  
 
IT STILL LOOKS LIKE MONDAY OFFERS A BETTER CHANCE AT SHOWERS AND  
THUNDERSTORMS ACROSS A WIDER PORTION OF SOUTHERN NEW ENGLAND THAN  
COMPARED TO THE WEEKEND, AS A STRONGER SHORTWAVE TROUGH IN MIDLEVELS  
AND AN ASSOCIATED SFC FRONT CROSS THE AREA DURING THE AFTERNOON TO  
EARLY EVENING. STILL PRETTY WEAK WIND FIELDS OVERALL, ALBEIT A TOUCH  
STRONGER THAN PRIOR DAYS. INSTABILITY VALUES ARE ALSO STILL ON THE  
LOWER SIDE. WOULDN'T RULE OUT A STRONGER CELL OR TWO BUT THINKING  
ANY STORMS WOULD BE MORE GARDEN-VARIETY THAN OTHERWISE. HIGHS ARE  
GENERALLY SIMILAR IN THE MIDDLE 80S, BUT WILL BE ACCOMPANIED BY  
INCREASED HUMIDITY LEVELS.  
 
TUESDAY THROUGH THURSDAY:  
 
WARMING TEMPERATURES AND INCREASED LEVELS OF HUMIDITY ARE  
ANTICIPATED FOR THIS PERIOD, AS SHORTWAVE RIDGING ALOFT BUILDS OVER  
AND JUST EAST OF SOUTHERN NEW ENGLAND. THIS SHOULD BRING INCREASING  
HEAT INDICES TO ELEVATED LEVELS, IN PARTICULAR FOR WED AND THURS.  
BOTH DAYS COULD FEATURE HEAT INDICES APPROACHING ADVISORY THRESHOLDS  
IN THE MID 90S TO LOW 100S, HIGHEST IN THE CT AND MERRIMACK VALLEYS.  
HIGH TEMPS STAND TO REACH INTO THE UPPER 80S TO MID 90S AWAY FROM  
THE COAST.  
 
IT LOOKS AS THOUGH THIS PERIOD IS GENERALLY DRY WITH SUBSIDENCE  
ALOFT GOVERNING OUR WEATHER. THAT SAID, THERE ARE STILL A SMALLER  
MINORITY OF GEPS/EPS MEMBERS WHICH SHOW SOME UNSETTLED WEATHER  
EMANATING FROM THE MID-ATLANTIC OFFSHORE WATERS/GULFSTREAM CURRENT  
MOVING OFF TOWARDS THE NE. WERE THIS TO TRANSPIRE, IT COULD BRING A  
RISK FOR CLOUDINESS AND SOME SHOWERS. WITH FEWER ENSEMBLE MEMBERS  
OFFERING THIS POTENTIAL, THIS WETTER OUTCOME ISN'T CURRENTLY  
REFLECTED IN THE FORECAST, BUT MAY NEED TO BE RE-CONSIDERED IF  
THERE ARE MORE ENSEMBLE MEMBERS WHICH SHOW RAINIER CONDITIONS.  
 
FRIDAY:  
 
FRIDAY COULD FEATURE ANOTHER DAY OF ELEVATED HEAT AND HUMIDITY, BUT  
MOST OF THE ENSEMBLE MEANS SHOW AN APPROACHING COLD FRONT WITH  
HIGHER-END CHANCE POPS FOR SHOWERS AND THUNDERSTORMS COMING IN  
DURING THE AFTERNOON. FLOW ALOFT IS SEASONABLY STRONG AND COULD  
POINT TO A FEW STRONGER STORMS AROUND AS THE FRONT SAGS SOUTHWARD  
BUT STILL ENOUGH TIME TO DRILL INTO THOSE DETAILS IN THE COMING DAYS  
AHEAD.  
 

 
   
AVIATION /00Z SATURDAY THROUGH WEDNESDAY/
 
 
FORECASTER CONFIDENCE LEVELS...  
 
LOW - LESS THAN 30 PERCENT.  
MODERATE - 30 TO 60 PERCENT.  
HIGH - GREATER THAN 60 PERCENT.  
 
00Z TAF UPDATE:  
 
TONIGHT: HIGH CONFIDENCE IN TAF/TRENDS, THOUGH MODERATE ON  
TIMING.  
 
ISOLATED TSRA VICINITY OF BED AND BAF TO DISSIPATE BY 01Z. VFR  
INITIALLY BUT IFR TO LIFR STRATUS AND FOG RETURN FROM SOUTH TO  
NORTH DURING THE EVENING/OVERNIGHT. LIGHT S TO SE WINDS.  
 
SATURDAY: MODERATE CONFIDENCE.  
 
VFR/MVFR. SIMILAR PATTERN TO FRIDAY: SE WINDS WITH CLOUDS TO  
START AND SOME CLEARING EXPECTED IN THE AFTERNOON. MODERATE  
CONFIDENCE IN THE TIMING FOR IMPROVEMENTS FROM THE MORNING.  
ISOLATED SHOWERS AND THUNDERSTORMS POSSIBLE ONCE AGAIN, MAINLY  
IN WESTERN MA.  
 
SATURDAY NIGHT: MODERATE TO HIGH CONFIDENCE.  
 
ANY TSRA THEN WEAKENS AND DISSIPATES SHORTLY AFTER SUNDOWN. VFR,  
BUT WITH IFR TO LIFR STRATUS AND FOG, THOUGH ITS NORTHWARD  
EXTENT COULD BE MORE LIMITED THAN PRIOR NIGHTS.  
 
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.  
 
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.  
 
OUTLOOK /SUNDAY THROUGH WEDNESDAY/...  
 
SUNDAY: VFR.  
 
SUNDAY NIGHT: MAINLY VFR, WITH LOCAL MVFR POSSIBLE. SLIGHT  
CHANCE SHRA.  
 
MONDAY: MAINLY VFR, WITH LOCAL MVFR POSSIBLE. CHANCE SHRA,  
CHANCE TSRA.  
 
MONDAY NIGHT: VFR. SLIGHT CHANCE SHRA, SLIGHT CHANCE TSRA.  
 
TUESDAY THROUGH TUESDAY NIGHT: VFR.  
 
WEDNESDAY: BREEZY.  
 

 
   
MARINE
 
 
FORECASTER CONFIDENCE LEVELS...  
 
LOW - LESS THAN 30 PERCENT.  
MEDIUM - 30 TO 60 PERCENT.  
HIGH - GREATER THAN 60 PERCENT.  
 
TONIGHT THROUGH SATURDAY NIGHT...HIGH CONFIDENCE.  
 
WEAK PRESSURE GRADIENT WILL KEEP WINDS/SEAS BELOW SMALL CRAFT  
ADVISORY THRESHOLDS THROUGH SATURDAY: SEAS 2-4 FT WITH E WINDS  
OVER THE SOUTHERN WATERS AND SE WINDS OVER THE EASTERN WATERS UP  
TO 15 KTS DURING THE AFTERNOON HOURS, REMAINING LIGHT IN THE  
OVERNIGHT HOURS. MAIN CONCERN FOR MARINERS WILL BE AREAS OF FOG  
TONIGHT THAT MAY REDEVELOP SATURDAY NIGHT.  
 
OUTLOOK /SUNDAY THROUGH WEDNESDAY/...  
 
SUNDAY THROUGH SUNDAY NIGHT: WINDS LESS THAN 25 KT.  
 
MONDAY: WINDS LESS THAN 25 KT. SLIGHT CHANCE OF RAIN SHOWERS.  
 
MONDAY NIGHT THROUGH WEDNESDAY: WINDS LESS THAN 25 KT.  
 

 
   
BOX WATCHES/WARNINGS/ADVISORIES
 
 
CT...NONE.  
MA...NONE.  
RI...NONE.  
MARINE...NONE.  
 

 
 

 
 
SYNOPSIS...LOCONTO/HRENCECIN  
NEAR TERM...HRENCECIN  
SHORT TERM...HRENCECIN  
LONG TERM...LOCONTO  
AVIATION...LOCONTO/HRENCECIN  
MARINE...LOCONTO/HRENCECIN  
 
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