259  
FXUS61 KBOX 312333  
AFDBOX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE BOSTON/NORTON MA  
733 PM EDT TUE MAR 31 2026  
   
WHAT HAS CHANGED  
 
UPDATED AVIATION SECTION.  
 
THERE IS A MARGINAL RISK FOR A STRONG TO SEVERE THUNDERSTORM  
THIS EVENING, MAINLY ACROSS WESTERN MA AND CT.  
 
 
   
KEY MESSAGES  
 
- SCATTERED SHOWERS AND THUNDERSTORMS THIS EVENING WITH A STRONG TO  
SEVERE STORM POSSIBLE OVER WESTERN MA  
 
- UNSETTLED WEATHER CONTINUES INTO WEDNESDAY AND WEDNESDAY NIGHT  
 
- MILDER AND UNSETTLED PATTERN LATER THIS WEEK BRINGS SHOWERS FROM  
TIME TO TIME ALONG WITH WARMER TEMPERATURES FOR INLAND LOCATIONS.  
 
 
   
DISCUSSION  
 
KEY MESSAGE 1...SCATTERED SHOWERS AND THUNDERSTORMS THIS EVENING  
WITH A STRONG TO SEVERE STORM POSSIBLE OVER WESTERN MA  
 
SHORT-WAVE ENERGY EMBEDDED WITHIN LARGER SCALE ZONAL FLOW ALOFT  
WILL HELP TRIGGER SHOWERS AND THUNDERSTORMS THIS EVENING OVER  
WESTERN MA/CT. THE LATEST CONVECTIVE OUTLOOK FROM THE STORM  
PREDICTION CENTER PLACES WESTERN MA AND CT IN A MARGINAL RISK  
FOR SEVERE STORM WITH A GENERAL THUNDERSTORM RISK ELSEWHERE IN  
SOUTHERN NEW ENGLAND.  
 
THE OVERALL STRENGTH OF SYNOPTIC FORCING FOR ASCENT IN THE  
ATMOSPHERE WILL BE ON THE WEAK SIDE TONIGHT. FURTHERMORE,  
INSTABILITY WILL BE LIMITED TO THE TUNE OF 250-500 J/KG OF  
MLCAPE. WHILE SUFFICIENT FOR THUNDERSTORM DEVELOPMENT, THESE  
NUMBERS DO NOT PRESENT AN ALARMING SCENARIO FOR SEVERE WEATHER.  
DEEP LAYER SHEAR WILL BE STRONG WITH 40-50 KNOTS OF SHEAR IN  
THE 0-6 KM LAYER. THUS, WE HAVE THE INGREDIENTS NEEDED FOR A  
PERIOD OF CONVECTION.  
 
IF WE CONSULT THE LATEST SUITE OF HI- RESOLUTION MODEL  
GUIDANCE, WE FIND THAT 00-06Z (8PM-2AM), WILL BE THE BEST  
OPPORTUNITY FOR THUNDERSTORMS ACROSS SOUTHERN NEW ENGLAND. HI-  
RES GUIDANCE KEEPS THE MOST ROBUST ACTIVITY MAINLY ALONG AND  
NORTH OF THE I-90 CORRIDOR. CSU ML PROBABILITIES GIVE A 5-10%  
CHANCE OF SEVERE THUNDERSTORM WIND GUSTS OR LARGE HAIL FOR  
WESTERN MA. FURTHER EAST, LIGHTNING AND PERIODS OF HEAVY  
RAINFALL WOULD BE THE MOST LIKELY HAZARDS. EXPECT THUNDERSTORM ACTIVITY  
TO WANE AFTER MIDNIGHT AS INSTABILITY DIMINISHES.  
 
KEY MESSAGE 2...UNSETTLED WEATHER CONTINUES INTO WEDNESDAY AND  
WEDNESDAY NIGHT  
 
A WIND SHIFT TO THE WEST/SOUTHWEST EARLY WEDNESDAY WILL SUPPORT  
ANOTHER MILD AFTERNOON IN SOUTHERN NEW ENGLAND WITH MANY  
LOCATIONS REACHING THE UPPER 60S TO LOW 70S. THE PRESENCE OF A  
FRONTAL WAVE MOVING OVER THE NORTHEAST WILL CONTINUE TO KEEP  
THINGS UNSETTLED WITH INTERMITTENT PERIODS OF SHOWERS EXPECTED  
DURING THE DAY WEDNESDAY. A LULL IN SHOWER ACTIVITY IS EXPECTED  
WEDNESDAY AFTERNOON, BUT A COLD FRONT SAGGING SOUTH WILL  
SUPPORT AN ADDITIONAL ROUND OF SHOWERS WEDNESDAY NIGHT INTO  
THURSDAY, MAINLY ALONG AND SOUTH OF THE I-90 CORRIDOR. LATEST  
MODEL GUIDANCE RESOLVES THE MOST SHOWER ACTIVITY OVER THE SOUTH  
COAST OF MA AND RI. CHILLIER TEMPERATURES SETTLE IN WEDNESDAY  
NIGHT WITH LOWS TEMPERATURES FALLING TO THE 30S BY THURSDAY  
MORNING.  
 
KEY MESSAGE 3...MILDER AND UNSETTLED PATTERN LATER THIS WEEK BRINGS  
SHOWERS FROM TIME TO TIME ALONG WITH WARMER TEMPERATURES FOR INLAND  
LOCATIONS.  
 
BEYOND WEDNESDAY WE'RE IN FOR A BIG COOLDOWN AS 1040MB HIGH PRESSURE  
MOVES INTO NOVA SCOTIA AND SURFACE WINDS VEER TO THE NORTHEAST  
PUSHING A COLD FRONT THE REST OF THE WAY THROUGH THE REGION. THIS,  
COMBINED WITH STUBBORN LOW CLOUDS WILL KEEP HIGH TEMPERATURES VERY  
COLD COMPARED TO WEDNESDAY, IN THE UPPER 30S AND LOW 40S. THIS WILL  
BE A 30 DEGREE DIFFERENCE IN HIGH TEMPERATURES FOR SOME LOCATIONS!  
THE ROLLER COASTER CONTINUES ON FRIDAY AS THE FRONT LIFTS BACK TO  
THE NORTH BRINGING WARMER TEMPS IN THE 60S AND EVEN SOME 70S BY THE  
WEEKEND. THAT BEING SAID, IT REMAINS A VERY CHAOTIC AND DYNAMIC  
PATTERN WITH SNE SANDWICHED BETWEEN A SUBTROPICAL RIDGE AND EAST  
COAST TROUGH SO CONFIDENCE IN THE TEMPERATURE FORECAST IS LOW TO  
MODERATE. SAME WITH EXACT TIMING AND PLACEMENT OF ANY RAINFALL  
ASSOCIATED WITH THESE FRONTAL PASSAGES AND PASSING SHORTWAVES. A  
GENERALLY UNSETTLED PATTERN WITH SCATTERED RAIN SHOWERS LOOKS TO  
HOLD ON THROUGH THE EARLY PART OF THE WEEKEND BEFORE A MORE  
APPRECIABLE FRONT AND MID LEVEL TROUGH MOVE THROUGH AROUND  
SUNDAY/SUNDAY NIGHT.  
 
 
   
AVIATION /00Z WEDNESDAY THROUGH SUNDAY/  
 
LOW - LESS THAN 30 PERCENT.  
MODERATE - 30 TO 60 PERCENT.  
HIGH - GREATER THAN 60 PERCENT.  
 
00Z TAF UPDATE...MODERATE CONFIDENCE.  
 
BACKDOOR FRONT WAS SETTLING NEAR A LINE FROM ORE-PVD THIS  
EVENING. MVFR/IFR CEILINGS WITH NE WINDS IN ITS WAKE WILL  
IMPROVE OVERNIGHT ONCE FRONT LIFTS BACK TO NORTH. VFR TO WEST OF  
FRONT WITH S WINDS. WATCHING TSRA MOVING THROUGH EASTERN NY  
WHICH SHOULD WEAKEN AS IT REACHES SNE, MAINLY BRINGING SHRA AND  
AN EMBEDDED TS ALONG AND NORTH OF I-90 UNTIL AROUND MIDNIGHT.  
 
LLWS EXPECTED OVERNIGHT, ESPECIALLY NEAR COAST, WITH 020 WINDS  
230-240/50-60KT.  
 
SCATTERED SHOWERS EXPECTED WED MORNING WITH S/SW WINDS, THEN  
BACKDOOR FRONT ONCE AGAIN DROPS S DURING AFTERNOON AND EVENING,  
THIS TIME TO MORE OF SOUTHERN NEW ENGLAND, WITH WIND SHIFT TO  
N/NE AND LOWERING CEILINGS TO MVFR/IFR. ALSO EXPECTING A PERIOD  
OF SHOWERS, MAINLY FOCUSED NEAR SOUTH COAST, LATER IN DAY.  
 
KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. TIMING OF  
IMPROVEMENT LATER TONIGHT MAY BE TOO QUICK AND THERE IS LOWER  
CONFIDENCE ON WHETHER OR NOT IFR CIGS RETURN WED AFTERNOON.  
 
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF BUT LOW CONFIDENCE IN  
TIMING OF ANY ISOLATED T-STORM RISK.  
 
OUTLOOK /WEDNESDAY NIGHT THROUGH SUNDAY/...  
 
THURSDAY: MAINLY MVFR, WITH AREAS IFR POSSIBLE. BREEZY. CHANCE  
RA, FZRA LIKELY.  
 
THURSDAY NIGHT: MAINLY MVFR, WITH AREAS IFR POSSIBLE. CHANCE  
RA.  
 
FRIDAY: MAINLY VFR, WITH LOCAL IFR POSSIBLE. BREEZY.  
 
FRIDAY NIGHT THROUGH SATURDAY: BREEZY. SLIGHT CHANCE RA.  
 
SATURDAY NIGHT: BREEZY. CHANCE RA.  
 
SUNDAY: WINDY WITH LOCAL GUSTS UP TO 30 KT. RA LIKELY.  
 
 
   
MARINE  
 
FORECASTER CONFIDENCE LEVELS...  
 
LOW - LESS THAN 30 PERCENT.  
MODERATE - 30 TO 60 PERCENT.  
HIGH - GREATER THAN 60 PERCENT.  
 
MODERATE SOUTHWEST WINDS OVERNIGHT BETWEEN 15 AND 25 KNOTS WITH  
STRONGEST WINDS OVER THE OUTER SOUTH COASTAL WATERS. A FEW  
MARGINAL GALE FORCE GUSTS ARE POSSIBLE. SCY IN PLACE THROUGH  
TOMORROW NIGHT. SEAS REMAIN ELEVATED OVER THE SOUTHERN MARINE  
ZONES AS WELL BUT GRADUALLY SUBSIDE FROM 7-10 FEET WEDNESDAY  
MORNING TO 4-6 FEET BY WEDNESDAY EVENING. WINDS SHIFT TO THE  
NORTHEAST WEDNESDAY NIGHT INTO THURSDAY BUT REMAIN MODERATELY  
STRONG WITH SUSTAINED WINDS BETWEEN 15 AND 20 KNOTS.  
 
OUTLOOK /WEDNESDAY NIGHT THROUGH SUNDAY/...  
 
THURSDAY: LOW RISK FOR SMALL CRAFT ADVISORY WINDS WITH GUSTS UP  
TO 25 KT. SEAS UP TO 5 FT. CHANCE OF RAIN.  
 
THURSDAY NIGHT: WINDS LESS THAN 25 KT. AREAS OF SEAS  
APPROACHING 5 FT. CHANCE OF RAIN.  
 
FRIDAY: LOW RISK FOR SMALL CRAFT ADVISORY WINDS WITH GUSTS UP  
TO 25 KT. AREAS OF SEAS APPROACHING 5 FT.  
 
FRIDAY NIGHT: MODERATE RISK FOR SMALL CRAFT ADVISORY WINDS WITH  
GUSTS UP TO 25 KT. SEAS UP TO 5 FT.  
 
SATURDAY: WINDS LESS THAN 25 KT. AREAS OF SEAS APPROACHING  
5 FT.  
 
SATURDAY NIGHT: LOW RISK FOR SMALL CRAFT ADVISORY WINDS WITH  
LOCAL GUSTS UP TO 30 KT. SEAS UP TO 5 FT. SLIGHT CHANCE OF  
RAIN.  
 
SUNDAY: STRONG WINDS WITH GUSTS UP TO 30 KT. AREAS OF ROUGH  
SEAS. CHANCE OF RAIN.  
 
 
   
BOX WATCHES/WARNINGS/ADVISORIES  
 
CT...NONE.  
MA...NONE.  
RI...NONE.  
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ231-  
250.  
SMALL CRAFT ADVISORY UNTIL 7 PM EDT WEDNESDAY FOR ANZ232>235-  
237.  
SMALL CRAFT ADVISORY UNTIL 2 PM EDT WEDNESDAY FOR ANZ236.  
SMALL CRAFT ADVISORY UNTIL 6 AM EDT THURSDAY FOR ANZ254>256.  
 
 
 
 
 
DISCUSSION...BW/RM  
AVIATION...JWD  
MARINE...RM  
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