084
FXUS61 KBOX 311816
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
216 PM EDT TUE MAR 31 2026
WHAT HAS CHANGED
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 /18Z TUESDAY THROUGH SUNDAY/
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
18Z TAF UPDATE...MODERATE CONFIDENCE
THROUGH 00Z...HIGH CONFIDENCE IN FLIGHT CATEGORIES. LOW CONFIDENCE
IN TIMING AND LOCATION OF RAIN SHOWERS.
LOW CLOUDS ASSOCIATED WITH A BACKDOOR COLD FRONT WILL SUPPORT
IFR/LIFR CEILINGS AT BOS/BED FOR THE REST OF THE AFTERNOON. SOUTH
AND WEST OF THE COLD FRONT, VFR CONDITIONS PREVAIL WITH STEADY
SOUTHWEST WINDS. INTERMITTENT PERIODS OF SHOWERS EXPECTED MAINLY
NORTH OF ORH AND BED, BUT A FEW SHOWERS WILL BE POSSIBLE ELSEWHERE.
TONIGHT...MODERATE CONFIDENCE
STEADIER RA MOVES IN FROM WEST TO EAST AFTER 00Z WITH -TSRA POSSIBLE
THROUGH 06Z. AREAS OF IFR/LIFR CEILING NEAR BOS/BED RETREAT EAST
AFTER 06Z WITH IMPROVEMENTS TO MVFR BETWEEN 06-12Z. VFR
CONDITIONS PREVAIL ELSEWHERE.
TOMORROW...MODERATE CONFIDENCE IN FLIGHT CATEGORIES, LOW
CONFIDENCE IN TIMING/LOCATION OF SHRA.
MVFR CEILINGS EARLY WITH SOME PASSING -SHRA. EXPECT IMPROVEMENTS TO
VFR BY MID-MORNING (14-16Z). MVFR CEILINGS REDEVELOP OVER THE SOUTH
COAST, CAPE, AND ISLANDS WITH ANOTHER ROUND OF SHRA MAINLY AFTER 18Z.
KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. BULK OF AFTERNOON SHOWER
ACTIVITY IS NORTH OF I-90, BUT INTERMITTENT PERIODS OF -SHRA AT BOS
LIKELY THROUGH THIS EVENING. -TSRA POSSIBLE BETWEEN 00-04Z BUT LOW
CONFIDENCE IN WHETHER OR NOT STORMS OCCUR OVER THE TERMINAL.
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF BUT LOW CONFIDENCE IN
TIMING OF ANY ISOLATED T-STORM RISK.
OUTLOOK /WEDNESDAY NIGHT THROUGH SUNDAY/...
WEDNESDAY NIGHT: MVFR/IFR CONDITIONS POSSIBLE. BREEZY. SHRA
LIKELY.
THURSDAY THROUGH THURSDAY NIGHT: MVFR/IFR CONDITIONS POSSIBLE.
BREEZY. CHANCE SHRA.
FRIDAY: MAINLY VFR, WITH LOCAL IFR POSSIBLE. BREEZY.
FRIDAY NIGHT THROUGH SATURDAY: BREEZY. SLIGHT CHANCE RA.
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/...
WEDNESDAY NIGHT: WINDS LESS THAN 25 KT. SEAS UP TO 5 FT. RAIN
SHOWERS LIKELY. LOCAL VISIBILITY 1 NM OR LESS.
THURSDAY: LOW RISK FOR SMALL CRAFT ADVISORY WINDS WITH GUSTS UP
TO 25 KT. SEAS UP TO 5 FT. CHANCE OF RAIN SHOWERS.
THURSDAY NIGHT: WINDS LESS THAN 25 KT. AREAS OF SEAS
APPROACHING 5 FT. CHANCE OF RAIN SHOWERS.
FRIDAY: LOW RISK FOR SMALL CRAFT ADVISORY WINDS WITH GUSTS UP
TO 25 KT. AREAS OF SEAS APPROACHING 5 FT.
FRIDAY NIGHT: LOW RISK FOR SMALL CRAFT ADVISORY WINDS WITH
GUSTS UP TO 25 KT. SEAS UP TO 5 FT. SLIGHT CHANCE OF RAIN.
SATURDAY: WINDS LESS THAN 25 KT. AREAS OF SEAS APPROACHING
5 FT. SLIGHT 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...RM
MARINE...RM
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