168  
FXUS61 KBOX 101808  
AFDBOX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE BOSTON/NORTON MA  
208 PM EDT THU JUL 10 2025  
   
SYNOPSIS
 
 
SEASONABLY WARM AND HUMID WEATHER WILL REMAIN IN CONTROL OF OUR  
WEATHER INTO THE FIRST HALF OF NEXT WEEK. ALTHOUGH THERE  
WILL BE DIURNALLY-DRIVEN SHOWER AND THUNDERSTORM CHANCES IN  
WESTERN MA AND CT THIS WEEKEND, MOST OF EASTERN MA AND RI SHOULD  
REMAIN DRY UNDER ONSHORE FLOW. A FRONTAL SYSTEM ON MONDAY  
OFFERS BETTER CHANCES AT SHOWERS AND THUNDERSTORMS ACROSS MOST  
OF SOUTHERN NEW ENGLAND. TEMPERATURES THEN WARM UP AROUND THE  
MIDDLE OF NEXT WEEK, BUT WILL HAVE TO MONITOR FOR POSSIBLE  
UNSETTLED WEATHER OFF THE MID-ATLANTIC WATERS.  
 

 
   
NEAR TERM /THROUGH TONIGHT/
 
 
KEY POINTS...  
 
* LINGERING SHOWERS TOWARDS THE CAPE AND ISLANDS DISSIPATE BY EARLY  
EVENING  
 
* A FEW SHOWERS/ISOLATED T-STORM OR TWO ALSO POSSIBLE ACROSS THE  
DISTANT INTERIOR THIS EVENING...BUT OTHERWISE DRY TONIGHT  
 
* AREAS OF FOG TONIGHT SOME OF WHICH MAY BECOME LOCALLY DENSE WITH  
LOW TEMPS IN THE 60S  
 
DETAILS...  
 
TONIGHT...  
 
A FEW LINGERING SHOWERS ARE POSSIBLE INTO EARLY THIS EVENING TOWARDS  
THE CAPE AND ISLANDS. OTHERWISE...ENOUGH DIURNAL HEATING AND  
MARGINAL INSTABILITY MAY GENERATE A FEW SHOWERS AND PERHAPS AN  
ISOLATED T-STORM OR TWO ACROSS THE DISTANT INTERIOR INTO THIS  
EVENING. GREATEST RISK FOR THIS WILL BE NEAR AND WEST OF THE CT  
RIVER.  
 
OTHERWISE...MOIST LOW LEVEL NORTHEAST FLOW COUPLED WITH DEWPOINTS IN  
THE 60S WILL RESULT IN WIDESPREAD LOW CLOUDS PERSISTING TONIGHT.  
THIS MAY ALSO LEAD TO AREAS OF FOG...WHICH COULD BE LOCALLY DENSE IN  
SPOTS ESPECIALLY NEAR THE COAST AND WORCESTER HILLS. LOW TEMPS  
TONIGHT WILL BE IN THE 60S.  
 

 
   
SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/
 
 
KEY POINTS...  
 
* WARM & HUMID FRI WITH PARTIAL SUNSHINE DEVELOPING FRI  
 
* HIGHS IN THE 80S FRI AWAY FROM THE IMMEDIATE COAST  
 
* A FEW STRONG TO MARGINALLY SEVERE T-STORMS POSSIBLE ACROSS  
THE INTERIOR FRI PM WITH LOCALIZED TORRENTIAL RAINFALL  
 
DETAILS...  
 
FRIDAY...  
 
THE LOW CLOUDS AND FOG SHOULD GRADUALLY BURN OFF FRIDAY MORNING AND  
ESPECIALLY BY AFTERNOON WITH THE HELP OF THE STRONG JULY SUN ANGLE.  
WITH AT LEAST PARTIAL SUNSHINE DEVELOPING...HIGH TEMPERATURES SHOULD  
REACH INTO THE 80S INLAND FROM THE IMMEDIATE COAST. DEWPOINTS IN THE  
UPPER 60S TO NEAR 70 WILL ALSO RESULT IN HUMID CONDITIONS. ON THE  
IMMEDIATE COAST...SEA BREEZES WILL KEEP HIGH TEMPS IN THE 75 TO 80  
DEGREE RANGE BUT IT STILL WILL BE HUMID.  
 
THE OTHER ISSUE WILL BE THE RISK FOR A FEW STRONG TO MARGINALLY  
SEVERE T-STORMS FRI AFTERNOON AND EVENING ACROSS THE INTERIOR. IT  
DOES LOOK LIKE WE SHOULD GENERATE MODEST INSTABILITY IN THE 1500 TO  
2000 J/KG RANGE WITH MARGINAL SHEAR ON THE ORDER OF 25 TO 30 KNOTS.  
POOR MID LEVEL LAPSE RATES AND LIMITED UPPER LEVEL SUPPORT WILL  
TEMPER THIS POTENTIAL. THAT BEING SAID...A FEW STRONG TO MARGINALLY  
SEVERE T-STORMS ARE POSSIBLE FRI AFTERNOON/EARLY EVENING BUT  
CERTAINLY NOT EXPECTING A SEVERE WEATHER OUTBREAK. MAIN RISK WOULD  
BE LOCALIZED STRONG TO DAMAGING WIND GUSTS WITH LOCALIZED TORRENTIAL  
RAINFALL. DRY WEATHER SHOULD PREVAIL ACROSS MOST OF THE COASTAL  
PLAIN WITH THE MAIN INSTABILITY/FORCING FOCUSED TO THE WEST.  
 
FRIDAY NIGHT...  
 
ANY WIDELY SCATTERED CONVECTION SHOULD COME TO AN END FRI EVENING.  
OTHERWISE...DRY WEATHER IS IN STORE FOR FRI NIGHT WITH LOW TEMPS IN  
THE 60S.  
 

 
   
LONG TERM /SATURDAY THROUGH WEDNESDAY/
 
 
KEY MESSAGES:  
 
* DRIER WITH ONSHORE FLOW IN EASTERN PORTION OF SOUTHERN NEW ENGLAND  
THIS WEEKEND, WITH DIURNALLY-DRIVEN SHOWERS/T-STORMS POSSIBLE EACH  
DAY THIS WEEKEND IN WESTERN MA AND CT. STILL RATHER HUMID BUT  
TEMPS AROUND OR SLIGHTLY COOLER THAN SEASONABLE.  
 
* BETTER CHANCE AT MORE WIDESPREAD SHOWERS/T-STORMS MONDAY, ALTHOUGH  
SEVERE WEATHER POTENTIAL LOOKS LIMITED.  
 
* TURNING VERY WARM TO HOT AROUND MID NEXT WEEK, BUT MONITORING  
POSSIBLE UNSETTLED WEATHER OFF THE MID-ATLANTIC COAST.  
 
DETAILS:  
 
THIS WEEKEND:  
 
OVERALL A PRETTY SIMILAR WEATHER PATTERN ANTICIPATED FOR THIS  
WEEKEND. SFC HIGH PRESSURE IN THE GULF OF MAINE FORCES A PERIOD OF  
ONSHORE ESE FLOW, WHILE A WEAKNESS IN THE 500 MB HEIGHT FIELD LENDS  
ITSELF TO MORE UNSETTLED CONDITIONS OVER DISTANT INTERIOR SOUTHERN  
NEW ENGLAND. WHILE MOST OF CENTRAL AND EASTERN MA AND RI SHOULD END  
UP SEEING DRIER CONDITIONS THAN NOT, A DAILY (MAINLY MID-AFTN TO  
EARLY EVENING) RISK FOR SCATTERED SLOW-MOVING SHOWERS OR  
THUNDERSTORMS ARE POSSIBLE FOR WESTERN MA AND CT IN VICINITY OF THE  
WEAK UPPER TROUGH AND ASSOCIATED WITH WEAK UPSLOPE FLOW. WITH WEAK  
FLOW ALOFT AND CAPE VALUES AROUND 1500 J/KG, PROBABLY NOT LOOKING AT  
SEVERE WEATHER WITH ANY STORMS, BUT LIGHTNING AND SLOW-MOVING  
DOWNPOURS ARE POSSIBLE IN ANY STORM WHICH DEVELOPS. DAILY EVENING TO  
OVERNIGHT RISK FOR PATCHY RADIATION FOG AND STRATUS AS WELL. HIGHS  
LOW TO MID 80S (MID/UPPER 70S CAPE AND ISLANDS WITH ONSHORE FLOW,  
WITH MID/UPPER 80S FOR INTERIOR SOUTHERN NEW ENGLAND.  
 
MONDAY:  
 
UNFORTUNATELY MONDAY OFFERS A BETTER CHANCE AT SHOWERS AND  
THUNDERSTORMS ACROSS A WIDER PORTION OF SOUTHERN NEW ENGLAND, AS A  
STRONGER SHORTWAVE TROUGH IN MIDLEVELS AND AN ASSOCIATED SFC FRONT  
CROSS THE AREA DURING THE AFTERNOON TO EARLY EVENING. WIND FIELDS  
ALOFT AT A LITTLE STRONGER THAN DURING THE WEEKEND, THOUGH THEY'RE  
STILL BETTER CHARACTERIZED AS WEAK, AND INSTABILITY VALUES ARE ALSO  
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 MID 80S AND STILL RATHER HUMID.  
 
TUESDAY THROUGH THURSDAY:  
 
SOME UNCERTAINTY IN THE SPECIFIC DETAILS IN THIS PERIOD WITH RESPECT  
TO THE ANTICIPATED WEATHER PATTERN. MORE SPECIFICALLY THE GFS SHOWS  
AN AMPLIFYING RIDGE OVER THE OH VALLEY MOVING EASTWARD. ON THE OTHER  
HAND, THE ECMWF AND THE CANADIAN GEM ARE WEAKER/SLOWER TO ADVANCE  
THIS RIDGE EASTWARD, INSTEAD FAVORING A WEAKNESS IN THE HEIGHT  
FIELD/TROUGHINESS ALONG THE MID-ATLANTIC/NORTHEAST US COASTLINE. A  
MINORITY OF THE ECMWF/GEM MEMBERS EVEN SHOW SOME DIFFUSE AREA OF  
DISTURBED WEATHER MOVING NORTHWARD FROM THE MID-ATLANTIC/CAROLINAS.  
TEMPERATURES STAND TO BE QUITE A BIT WARMER THAN THE WEEKEND/MONDAY  
AND IT WILL ALSO BE QUITE A BIT MORE HUMID TOO, BUT THERE IS MORE  
UNCERTAINTY ON CLOUD COVER/RAIN CHANCES IN THIS PERIOD GIVEN THE  
DIFFERENCES IN ENSEMBLES. BECAUSE OF THAT UNCERTAINTY, DIDN'T REALLY  
STRAY FAR FROM THE NATIONALBLEND. HIGHS IN THE UPPER 80S TO  
LOWER 90S.  
 

 
   
AVIATION /18Z THURSDAY THROUGH MONDAY/
 
 
FORECASTER CONFIDENCE LEVELS...  
 
LOW - LESS THAN 30 PERCENT.  
MODERATE - 30 TO 60 PERCENT.  
HIGH - GREATER THAN 60 PERCENT.  
 
18Z TAF UPDATE...  
 
THIS AFTERNOON & TONIGHT...HIGH CONFIDENCE.  
 
A FEW LINGERING SHOWERS MAY PERSIST INTO EARLY EVENING NEAR THE CAPE  
AND ISLANDS. WE MAY ALSO SEE A FEW SPOT SHOWERS/ISOLATED T-STORMS  
INTO THE EVENING ACROSS THE DISTANT INTERIOR. OVERALL THOUGH THE  
WEATHER SHOULD REMAIN DRY FOR MANY LOCATIONS.  
 
IFR WITH SOME MVFR CONDITIONS ACROSS THE INTERIOR THIS AFTERNOON  
WILL LOWER BACK TO MAINLY IFR/LIFR THIS EVENING WITH A COOLING  
BOUNDARY LAYER. WE ALSO WILL NEED TO WATCH FOR THE DEVELOPMENT OF  
FOG...SOME OF WHICH MAY BECOME LOCALLY DENSE NEAR THE COAST AND  
WORCESTER HILLS BUT THAT REMAINS MORE UNCERTAIN THAN THE LOWER  
CEILINGS. LIGHT/CALM WINDS.  
 
FRIDAY...HIGH CONFIDENCE IN TRENDS BUT LOWER CONFIDENCE IN TIMING.  
 
THE LOW CLOUDS AND FOG PATCHES SHOULD BURN OFF IN MOST LOCATIONS BY  
FRIDAY AFTERNOON ALLOWING MAINLY VFR CONDITIONS TO DEVELOP. A FEW  
STRONG THUNDERSTORMS WILL BE POSSIBLE FRI AFTERNOON AND EARLY  
EVENING ACROSS PARTS OF INTERIOR MA & CT...BUT IT SHOULD REMAIN DRY  
NEAR THE COAST. WINDS WILL MAINLY BE LIGHT FROM AN ESE/SE DIRECTION.  
 
FRIDAY NIGHT...MODERATE CONFIDENCE.  
 
ANY ISOLATED CONVECTION ACROSS THE INTERIOR WOULD WIND DOWN FRI  
EVENING. OTHERWISE...VFR CONDITIONS DOMINATE IN THE EVENING BUT MAY  
SEE SOME MVFR-IFR CONDITIONS DEVELOP OVERNIGHT WITH THE LINGERING  
LOW LEVEL MOISTURE. LIGHT S WINDS.  
 
KBOS TERMINAL...HIGH CONFIDENCE IN LOW CEILINGS WITH MORE  
UNCERTAINTY ON HOW MUCH FOG DEVELOPS TONIGHT.  
 
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.  
 
OUTLOOK /SATURDAY THROUGH MONDAY/...  
 
SATURDAY: VFR. SLIGHT CHANCE SHRA, SLIGHT CHANCE TSRA.  
 
SATURDAY NIGHT THROUGH SUNDAY: MAINLY VFR, WITH LOCAL MVFR  
POSSIBLE.  
 
SUNDAY NIGHT: VFR. SLIGHT CHANCE SHRA.  
 
MONDAY: VFR. CHANCE SHRA, CHANCE TSRA.  
 

 
   
MARINE
 
 
FORECASTER CONFIDENCE LEVELS...  
 
LOW - LESS THAN 30 PERCENT.  
MEDIUM - 30 TO 60 PERCENT.  
HIGH - GREATER THAN 60 PERCENT.  
 
TONIGHT THROUGH FRIDAY NIGHT...HIGH CONFIDENCE.  
 
WEAK PRESSURE GRADIENT WILL KEEP WINDS/SEAS BELOW SMALL CRAFT  
ADVISORY THRESHOLDS THROUGH FRIDAY NIGHT. MAIN CONCERN FOR MARINERS  
WILL BE AREAS OF FOG...SOME OF WHICH MAY BE LOCALLY DENSE  
PARTICULARLY TONIGHT INTO MID-MORNING FRIDAY.  
 
OUTLOOK /SATURDAY THROUGH MONDAY/...  
 
SATURDAY THROUGH MONDAY: WINDS LESS THAN 25 KT.  
 

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

 
 

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