483  
FXUS61 KBOX 261909  
AFDBOX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE BOSTON/NORTON MA  
309 PM EDT SUN OCT 26 2025  
   
SYNOPSIS
 
 
CANADIAN HIGH PRESSURE WILL KEEP COOL CONDITIONS AROUND FOR THE  
START OF THE WORK WEEK, WITH MAINLY DRY WEATHER TONIGHT AND  
TOMORROW. AS THIS HIGH SHIFTS FURTHER EAST ACROSS  
QUEBEC...ONSHORE FLOW MAY BRING SOME SCATTERED SHOWERS MAINLY  
NEAR THE COAST ON TUESDAY AND WEDNESDAY. A LOW PRESSURE SYSTEM  
MAY BRING A PERIOD OF RAIN AND GUSTY WINDS SOMETIME THURSDAY  
INTO FRIDAY, BUT OVERALL IMPACTS LOOK TO BE ON THE MINOR SIDE AT  
THIS POINT.  
 

 
   
NEAR TERM /THROUGH TONIGHT/
 
 
UPPER-LEVEL COLD POOL REMAINS PARKED OVER THE GULF OF MAINE  
OVERNIGHT, WITH WEAK SUBSIDENCE FROM NVA OVER SNE. SKIES ARE  
EXPECTED TO REMAIN CLEAR OVERNIGHT, WITH LITTLE TO NO WIND. WITH  
GREAT RADIATIONAL COOLING CONDITIONS AND TOO COLD AN AIR MASS  
ALREADY IN PLACE, OVERNIGHT LOWS WILL TUMBLE INTO THE UPPER 20S TO  
LOW 30S AWAY FROM URBAN AREAS AND THE COASTS.  
 

 
   
SHORT TERM /MONDAY THROUGH MONDAY NIGHT/
 
 
STALLED UPPER-LEVEL COLD POOL SENDS SOME WEAK SHORTWAVE ENERGY ALONG  
WITH A REINFORCING SHOT OF COLD AIR ADVECTION INTO THE REGION FOR  
TOMORROW. 850MB TEMPS DROP SLIGHTLY TO -5C, WHICH, COMBINED WITH A  
MORE NORTHERLY WIND AND CHILLY START, HIGH TEMPS WILL BE A FEW  
DEGREES COOLER THAN TODAY, IN THE UPPER 40S TO LOW 50S. SKIES TURN  
PARTLY TO MOSTLY CLOUDY TOMORROW AS STRATOCUMULUS FORMS, ESPECIALLY  
NEAR THE EASTERN WATERS.  
 
CHILLY AGAIN OVERNIGHT MONDAY INTO TUESDAY AS WINDS BECOME LIGHT.  
LOWS WILL AGAIN DROP INTO THE UPPER 20S TO LOW 30S AWAY FROM URBAN  
AREAS AND THE COASTS. THERE COULD BE ISOLATED OCEAN EFFECT SHOWERS  
NEAR THE CAPE AND ISLANDS OVERNIGHT AS NORTHERLY WINDS BEGIN TO  
INCREASE.  
 

 
   
LONG TERM /TUESDAY THROUGH SUNDAY/
 
 
KEY MESSAGES:  
 
* COOLER TEMPERATURES WITH BREEZY NORTHEAST WINDS THROUGH WEDNESDAY.  
 
* NEXT CHANCE FOR WIDESPREAD RAIN LATE IN THE WEEK, THOUGH THERE IS  
UNCERTAINTY WITH EXACT DETAILS.  
 
IT'S HARD TO BELIEVE, BUT HERE COMES THE FINAL WEEK OF OCTOBER AND  
THIS COMING WEEK FEATURES PERIODS OF UNSETTLED CONDITIONS. LET'S GET  
INTO THE OVERALL DETAILS.  
 
TUESDAY AND WEDNESDAY:  
 
1030+ HPA AREA OF HIGH PRESSURE REMAINS ANCHORED ACROSS EASTERN  
CANADA TUESDAY INTO EARLY THURSDAY, BEFORE WEAKENING. ON TUESDAY, A  
SOUTHERN STREAM SHORTWAVE AND LOW PRESSURE EXITS OFF THE SOUTHEAST  
COAST AND HEADS NORTHEAST TOWARDS BERMUDA AND THEN OUT INTO THE  
NORTH ATLANTIC. RESULTING PRESSURE GRADIENT ACROSS SOUTHERN NEW  
ENGLAND FAVORS NORTHEAST FLOW, COMING OFF THE GULF OF MAINE, WITH  
SST AROUND THE MID-50S. COMBINED WITH A MID-LEVEL LOW AND COLD POOL,  
WILL HAVE BELOW NORMAL TEMPERATURES BETWEEN THE LOW AND MID-50S AT  
THE COASTAL AND UPPER-40S ACROSS HIGHER TERRAIN OF NORTHERN AND  
WESTERN MASSACHUSETTS. NIGHTTIME LOWS ARE SEASONABLY COOL IN THE 30S  
AND MIDDLE-40S AT THE COAST.  
 
ORIENTATION OF THE FLOW CAN RESULT IN OCEAN EFFECT CLOUDS AND/OR  
SHOWER ACTIVITY. MODERATE CONFIDENCE IN THIS, WHICH WOULD AFFECT  
MAINLY EASTERN MASSACHUSETTS; CAPE ANN, CAPE COD, AND THE ISLANDS.  
DID OPT TO CAP POPS AT 'SLIGHT CHANCE' AS PWATS ARE LOW, LESS THAN  
80% OF AVERAGE, THESE WOULD BE MORE OF SPRINKLES OR LIGHT RAIN.  
 
THURSDAY AND FRIDAY:  
 
ROUNDING OUT THE WEEK BRINGS OUR NEXT CHANCE OF APPRECIABLE RAINFALL  
TO SOUTHERN NEW ENGLAND, BUT THERE REMAINS UNCERTAINTY WITH OVERALL  
TIMING DURING THIS FORECAST PERIOD. WEDNESDAY NIGHT INTO THURSDAY A  
POWERFUL SHORTWAVE EJECTS FROM THE ROCKIES, DIVES SOUTH TO THE GULF  
COAST, AND ABSORBS THE EXISTING SHORTWAVE THAT WAS OVER NEW ENGLAND.  
AT SURFACE LEVEL, LOW PRESSURE DEVELOPS AND STRENGTHENS QUICKLY AS  
IT RACES FROM THE SOUTHEASTERN CONUS TO THE NORTHEASTERN CONUS. WILL  
SAY, THE ENSEMBLE SPREAD IN THE POSITION OF THIS LOW IS VAST, HENCE  
THE LEVEL OF UNCERTAINTY WITH THIS PERIOD OF THE FORECAST. ANOTHER  
FEATURE THAT COULD INFLUENCE IS T.C. MELISSA. OFFICIAL FORECAST FROM  
NHC WOULD BRING MELISSA NEAR BERMUDA EARLY FRIDAY, WILL HAVE TO SEE  
OF THE SYSTEM TO THE WEST INTERACTS WITH THE T.C. AS THERE ARE SIGNS  
SOME OF THE TROPICAL MOISTURE MAY ADVECT NORTH AND ENHANCE RAINFALL.  
 
IT'S TOO EARLY TO SPECULATE ON HOW MUCH RAIN, BUT SIGNALS ARE THERE  
FOR SOAKING RAIN SOMETIME LATE THURSDAY INTO FRIDAY. PWATS SURGE AND  
REACH 2-3 STANDARD DEVIATIONS ABOVE NORMAL, POTENTIALLY INFLUENCED  
BY MELISSA'S TROPICAL ORIGINS. THE PROBABILITY OF AT LEAST 1.0" FROM  
THURSDAY NIGHT INTO FRIDAY NIGHT ARE 60 TO 80%. WITH 30 TO 50%  
PROBABILITIES OF AT LEAST 2.0". DAY 5 MRGL ERO FOR PARTS OF SOUTHERN  
NEW ENGLAND HAVE BEEN ISSUED AS A RESULT.  
 
GIVEN INHERENT UNCERTAINTIES WITH T.C. THIS FAR OUT, THERE IS A LOT  
OF TIME FOR ADJUSTMENTS TO THE FORECAST. SIDE NOTE: GIVEN FALL LEAF  
LITTER IN STORM DRAINS, BEING PROACTIVE AND REMOVING THE LEAF LITTER  
CAN REDUCE THE RISK OF POOR DRAINAGE FLOODING... WHICH BY DEFINITION  
IS NOT FLASH FLOODING.  
 

 
   
AVIATION /18Z SUNDAY THROUGH FRIDAY/
 
 
FORECASTER CONFIDENCE LEVELS...  
 
LOW - LESS THAN 30 PERCENT.  
MODERATE - 30 TO 60 PERCENT.  
HIGH - GREATER THAN 60 PERCENT.  
 
TONIGHT...HIGH CONFIDENCE.  
 
VFR WITH NW WINDS AROUND 5-10 KNOTS. CHANCE FOR PATCHY RADIATION  
FOG IN LOW LYING AREAS.  
 
MONDAY...HIGH CONFIDENCE  
 
VFR WITH PERIODS OF MVFR POSSIBLE NEAR THE CAPE AND ISLANDS IN  
THE AFTERNOON. NORTH WINDS AT 5-10 KNOTS.  
 
MONDAY NIGHT...HIGH CONFIDENCE  
 
VFR EXCEPT FOR MVFR NEAR THE CAPE AND ISLANDS. OCEAN EFFECT  
SHOWERS POSSIBLE NEAR THE CAPE AND ISLANDS. WINDS REMAIN LIGHT  
FROM THE NORTH.  
 
KBOS TERMINAL... HIGH CONFIDENCE IN TAF.  
 
VFR. NW WINDS AROUND 10 KNOTS TODAY  
 
KBDL TERMINAL... HIGH CONFIDENCE IN TAF.  
 
VFR. LIGHT N WINDS UNDER 10 KNOTS TODAY.  
 
OUTLOOK /TUESDAY THROUGH FRIDAY/...  
 
TUESDAY: MAINLY VFR, WITH LOCAL MVFR POSSIBLE. BREEZY. CHANCE  
SHRA.  
 
TUESDAY NIGHT THROUGH WEDNESDAY: MAINLY VFR, WITH AREAS MVFR  
POSSIBLE. BREEZY. CHANCE SHRA.  
 
WEDNESDAY NIGHT: MAINLY VFR, WITH LOCAL MVFR POSSIBLE. BREEZY.  
SLIGHT CHANCE SHRA.  
 
THURSDAY: VFR. BREEZY. CHANCE SHRA.  
 
THURSDAY NIGHT: MAINLY MVFR, WITH LOCAL IFR POSSIBLE. WINDY  
WITH LOCAL GUSTS UP TO 30 KT. CHANCE SHRA.  
 
FRIDAY: MVFR/IFR CONDITIONS POSSIBLE. WINDY WITH AREAS OF GUSTS  
UP TO 30 KT. CHANCE SHRA.  
 

 
   
MARINE
 
 
FORECASTER CONFIDENCE LEVELS...  
 
LOW - LESS THAN 30 PERCENT.  
MEDIUM - 30 TO 60 PERCENT.  
HIGH - GREATER THAN 60 PERCENT.  
 
TONIGHT THROUGH MONDAY NIGHT...HIGH CONFIDENCE.  
 
NW WINDS BEGIN TO SHIFT MORE NORTHERLY ON MONDAY, REMAINING AROUND  
10-15 KNOTS WITH 2-4 FOOT SEAS. WINDS REMAIN NORTH MONDAY NIGHT,  
BUT BEGIN TO INCREASE TO 20-25 KNOTS BY DAYBREAK TUESDAY. SEAS  
REMAIN 2-4 FEET OVERNIGHT.  
 
OUTLOOK /TUESDAY THROUGH FRIDAY/...  
 
TUESDAY: MODERATE RISK FOR SMALL CRAFT ADVISORY WINDS WITH  
LOCAL GUSTS UP TO 30 KT. SEAS UP TO 5 FT. CHANCE OF RAIN  
SHOWERS.  
 
TUESDAY NIGHT: STRONG WINDS WITH GUSTS UP TO 30 KT. ROUGH SEAS  
UP TO 10 FT. CHANCE OF RAIN SHOWERS.  
 
WEDNESDAY: STRONG WINDS WITH LOCAL GUSTS UP TO 30 KT. ROUGH  
SEAS UP TO 11 FT. CHANCE OF RAIN SHOWERS.  
 
WEDNESDAY NIGHT THROUGH THURSDAY: LOW RISK FOR SMALL CRAFT  
ADVISORY WINDS WITH GUSTS UP TO 25 KT. ROUGH SEAS UP TO 11 FT.  
CHANCE OF RAIN SHOWERS.  
 
THURSDAY NIGHT: STRONG WINDS WITH GUSTS UP TO 35 KT. ROUGH SEAS  
UP TO 13 FT. RAIN SHOWERS LIKELY.  
 
FRIDAY: STRONG WINDS WITH GUSTS UP TO 35 KT. ROUGH SEAS UP TO  
13 FT. RAIN SHOWERS LIKELY. LOCAL VISIBILITY 1 TO 3 NM.  
 

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

 
 

 
 
SYNOPSIS...DOOLEY/KP  
NEAR TERM...KP  
SHORT TERM...KP  
LONG TERM...DOOLEY  
AVIATION...DOOLEY/KP  
MARINE...DOOLEY/KP  
 
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