845
FXUS61 KBOX 110607
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
207 AM EDT THU JUN 11 2026
WHAT HAS CHANGED
SMALL CRAFT ADVISORY ISSUED FOR THE SOUTHERN OUTER WATERS FROM
06Z THURSDAY TO 00Z FRIDAY.
KEY MESSAGES
- SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS EXPECTED
OVERNIGHT.
- HEAT ADVISORIES ADVISORIES REMAIN IN EFFECT FOR NORTHERN
CONNECTICUT AND MUCH OF INTERIOR MASSACHUSETTS FROM NOON
THURSDAY TO 8PM FRIDAY.
- A FEW SCATTERED STRONG TO SEVERE THUNDERSTORMS ARE POSSIBLE
THURSDAY AND FRIDAY.
- ABOVE NORMAL TEMPERATURES CONTINUE INTO NEXT WEEK. DECREASING
HUMIDITY AS WELL. WEEKEND LOOKING MOSTLY DRY, WHILE
UNCERTAINTY REMAINS HIGH REGARDING POTENTIAL FOR RAIN SHOWERS
EARLY NEXT WEEK.
DISCUSSION
KEY MESSAGE 1
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS
EXPECTED OVERNIGHT.
AN APPROACHING WARM FRONT PUSHES INTO THE REGION OVERNIGHT
BRINGING A ROUND OF SCATTERED SHOWERS AND ISOLATED ELEVATED
THUNDERSTORMS. POTENTIAL FOR SEVERE WILL BE HELD AT BAY AS 0-6KM
BULK SHEAR VALUES STAY BELOW 15KTS. STILL, SOME OF THE MACHINE
LEARNING GUIDANCE SHOWS A SLIGHT (5-15%) CHANCE FOR SOME
STRONGER STORMS. NOTABLY, THE HRRR NEURAL NETWORK STILL
HIGHLIGHTS THE POTENTIAL FOR SEVERE WINDS ACROSS FAR NORTHERN
MASSACHUSETTS OVERNIGHT. HIGHER CONFIDENCE PART OF THE FORECAST
IS AREAS OF HEAVY RAIN AS PWATS SURGE TO 1.9"-2.0" ACROSS MOST
OF SOUTHERN NEW ENGLAND OVERNIGHT INTO THURSDAY MORNING. THE
EXACT CORRIDOR OF THE MOST CONCENTRATED PRECIPITATION IS STILL
SOMEWHAT UNCERTAIN AS FORCING WILL BE SOMEWHAT WEAK AND
NEBULOUS. THERE MAY BE TWO CORRIDORS OF HEAVIER RAIN, ONE NEAR
NORTHWESTERN MASS, AND THE OTHER ACROSS THE CAPE AND ISLANDS AS
A WEAK LOW PRESSURE PASSES OFFSHORE.
KEY MESSAGE 2...HEAT ADVISORIES ADVISORIES REMAIN IN EFFECT FOR
NORTHERN CONNECTICUT AND MUCH OF INTERIOR MASSACHUSETTS FROM
NOON THURSDAY TO 8PM FRIDAY.
THE WARMEST AIR MASS OF THE SEASON SO FAR ARRIVES THURSDAY AND
FRIDAY AS 925 MB TEMPERATURES SOAR TO +25-29C. IN ADDITION TO
THE HEAT, HUMIDITY WILL INCREASE BEHIND A WARM FRONT AS IT MOVES
NORTH OF OUR CWA. SOUTHWEST FLOW BRINGS OPPRESSIVE 65-70 DEGREE
DEW POINT TEMPERATURES ESPECIALLY ACROSS INTERIOR MA AND
NORTHERN CT. THESE HIGH DEW POINTS COMBINED WITH TEMPERATURES
CLIMBING INTO THE LOW TO MID 90S WILL LEAD TO HEAT INDEX VALUES
APPROACHING THE UPPER 90S TO NEAR 100F THURSDAY AND LIKELY ABOVE
100F FRIDAY ACROSS THE CT RIVER VALLEY. AS SUCH, HEAT
ADVISORIES REMAIN IN EFFECT FOR THESE AREAS THROUGH 8PM FRIDAY.
BY FRIDAY, A BACKDOOR COLD FRONT WILL PROVIDE SOME RELIEF FROM
THE HEAT AS ONSHORE FLOW DEVELOP. LOWEST TEMPERATURES WILL BE
FOUND MAINLY EAST OF 495. FURTHER INLAND, TEMPERATURES SOAR TO
THE MIDDLE AND PERHAPS UPPER 90S WITH HEAT INDEX VALUES AS HIGH
AS 100-101 DEGREES FOR THE CT RIVER VALLEY. MODERATE HEAT-
RELATED IMPACTS EXPAND ACROSS THE REGION, WITH MAJOR IMPACTS
EXPECTED IN THE CT RIVER VALLEY, BOTH THURSDAY AND FRIDAY,
LEADING TO AN INCREASED RISK OF HEAT-RELATED ILLNESS FOR ANYONE
SPENDING EXTENDED TIME OUTDOORS WITHOUT ADEQUATE HYDRATION OR
ACCESS TO COOLING.
THERE IS STILL SOME UNCERTAINTY AS TO HOW FAR EAST HEAT INDEX
VALUES >95F EXPAND. THE LATEST GUIDANCE SHOWS APPARENT
TEMPERATURES INCREASING TO BETWEEN 90 AND 95 DEGREES IN THE
MERRIMACK VALLEY. WHILE JUST BELOW HEAT ADVISORY CRITERIA, THESE
TEMPERATURES ARE NO LESS DANGEROUS TO THOSE WITHOUT ADEQUATE
HYDRATION OR COOLING.
KEY MESSAGE 3...A FEW SCATTERED STRONG TO SEVERE THUNDERSTORMS
ARE POSSIBLE THURSDAY AND FRIDAY.
THE INCREASED HEAT AND HUMIDITY SET THE STAGE FOR IMPRESSIVE
LEVELS OF INSTABILITY THURSDAY AND FRIDAY. IN TERMS OF AGGREGATE
SEVERE WEATHER PROBABILITES, MACHINE LEARNING GUIDANCE CONTINUES
TO SHOW A 15-20 PERCENT CHANCE FOR SEVERE WIND POTENTIAL
THURSDAY AND FRIDAY. IN TERMS OF CAPE, GUIDANCE CONTINUES TO
SHOW MODERATE DESTABILIZATION WITH VALUES APPROACHING 1500-2000
J/KG ACROSS THE REGION. THE LIMITING FACTOR WILL BE WEAK SHEAR
AS VALUES OF 0-6KM BULK SHEAR STRUGGLE TO GET ABOVE 20KTS
THURSDAY AFTERNOON. FORCING WILL ALSO BE WEAK AND CONFINED TO
WESTERN PORTIONS OF THE CWA. GUIDANCE SHOWS ONLY MODEST HEIGHT
FALLS AS A WEAK SHORTWAVE MOVES THROUGH THE REGION THURSDAY
EVENING. STILL, ANY STORMS THAT DO FORM WILL HAVE THE
OPPORTUNITY TO TAP INTO THE RICHLY BUOYANT AND UNSTABLE AIRMASS.
NOTABLY, FORECAST SOUNDINGS SHOW MID LEVEL LAPSE RATES AROUND
6-7.5C/KM THURSDAY AFTERNOON AND EVENING. THE PRIMARY THREAT
WITH ANY STRONGER STORM WOULD BE COLD POOL-DRIVEN DAMAGING
WINDS.
KEY MESSAGE 4...ABOVE NORMAL TEMPERATURES CONTINUE INTO NEXT
WEEK. DECREASING HUMIDITY AS WELL. WEEKEND LOOKING MOSTLY DRY,
WHILE UNCERTAINTY REMAINS HIGH REGARDING POTENTIAL FOR RAIN
SHOWERS EARLY NEXT WEEK.
A WEAK HIGH PRESSURE SANDWICHED BETWEEN TWO FRONTS SHOULD
DOMINATE OUR WEATHER FOR MOST OF THIS WEEKEND. THE MAIN IMPACT
OF THESE FRONTS WILL BE LOWERED HUMIDITY. IT SHOULD STILL BE
PLENTY WARM FOR MOST, IF NOT OUTRIGHT HOT. AT LEAST THE PEAK
HEAT INDEX VALUES SHOULD REMAIN MAINLY IN THE 80S, WITH A FEW
LOCATIONS REACHING THE LOWER 90S.
STILL QUITE A BIT OF UNCERTAINTY WITH THE DETAILS OF THE
FORECAST EARLY NEXT WEEK. THE LATEST GUIDANCE STALLS YET ANOTHER
FRONT TOWARDS THE SOUTH COAST OF NEW ENGLAND AS A WEAK LOW
PRESSURE DEVELOPS TOWARDS NJ SOMETIME MONDAY NIGHT INTO TUESDAY.
THE FORCING LOOKS RATHER WEAK, BUT CANNOT COMPLETELY DISMISS THE
IDEA OF SCATTERED SHOWERS IN OUR AREA AT TIMES. A SUBTLE SHIFT
OF EVEN JUST 20 MILES TO THE SOUTH, AND THE FORECAST COULD BE
LARGELY DRY. THIS IS ONE OF THOSE DETAILS YET TO BE IRONED OUT.
CHANGES WITH LATER FORECASTS ARE EXPECTED.
AVIATION /06Z THURSDAY THROUGH MONDAY/
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
THROUGH TONIGHT...MODERATE CONFIDENCE.
LINGERING CHANCES FOR A FEW SPRINKLES THROUGH 09Z, MAINLY
ACROSS THE EASTERN AND CAPE TERMINALS, BUT CONFIDENCE REMAINS ON
THE LOWER END. VISBY'S DROP TO MVFR/IFR THROUGHOUT THE EARLY
MORNING HOURS, ESPECIALLY ALONG THE CAPE/ISLANDS.
THURSDAY...MODERATE CONFIDENCE.
GENERALLY MVFR/IFR CONDITIONS. IMPROVEMENT FROM SHOWERS AND FOG
OVERNIGHT WILL LIKELY BE SLOW (NOT UNTIL 12Z OR LATER). SOME
AREAS COULD BE ON THE CUSP OF LIFR CONDITIONS AS ANY LINGERING
SHOWERS PUSH OFFSHORE. SW WINDS CONTINUE THROUGH THE MORNING
HOURS, GENERALLY AROUND 10 KTS ONCE SHOWERS MOVE OUT. CHANCE THE
WINDS COULD BRIEFLY SWAP TO E/SE AT BOS LATER IN THE DAY, BUT
CONFIDENCE IS LOW.
THURSDAY NIGHT...MODERATE CONFIDENCE.
GENERALLY VFR/MVFR WITH LIGHTER WNW WINDS. ANOTHER ROUND OF
DIURNAL SHOWERS POSSIBLE, PRIMARILY ACROSS THE WESTERN
TERMINALS. THUNDER AND HIGH WIND GUSTS CAN'T BE RULED OUT IF
SHOWERS DO FORM, BUT THEY SHOULD BE QUICK MOVING IN NATURE.
AFTERWARDS, A RETURN TO VFR FOR THE INTERIOR. IFR CIGS AND
VISBYS LIKELY RETURN ALONG THE COASTAL AND CAPE/ISLAND
TERMINALS.
KBOS TERMINAL...MODERATE CONFIDENCE IN TAF.
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.
OUTLOOK /FRIDAY NIGHT THROUGH MONDAY/...
FRIDAY NIGHT: MAINLY VFR, WITH LOCAL IFR POSSIBLE. BREEZY.
CHANCE SHRA, SLIGHT CHANCE TSRA.
SATURDAY THROUGH SATURDAY NIGHT: VFR.
SUNDAY: VFR. BREEZY.
SUNDAY NIGHT: VFR. BREEZY. CHANCE SHRA, SLIGHT CHANCE TSRA.
MONDAY: VFR. CHANCE SHRA.
MARINE
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
THROUGH FRIDAY...HIGH CONFIDENCE.
SEAS 2-4 FEET FOR THE MAJORITY OF THE WATERS EXCEPT 3-5 FEET
ACROSS THE SOUTHERN OUTER WATERS TONIGHT. SW WINDS INCREASE TO
15-25 KT WITH GUSTS AS HIGH AS 30 KTS. AREAS OF SHOWERS AND
PERHAPS A THUNDERSTORM OR TWO THROUGH THURSDAY MORNING. SCA
CONDITIONS CONTINUE FOR THE SOUTHERN WATERS THURSDAY BEFORE
GRADUALLY SUBSIDING BY THE LATE EVENING.
OUTLOOK /FRIDAY NIGHT THROUGH MONDAY/...
FRIDAY NIGHT: WINDS LESS THAN 25 KT. CHANCE OF RAIN SHOWERS,
ISOLATED THUNDERSTORMS.
SATURDAY THROUGH SUNDAY: WINDS LESS THAN 25 KT.
SUNDAY NIGHT: WINDS LESS THAN 25 KT. SEAS LOCALLY APPROACHING
5 FT. CHANCE OF RAIN SHOWERS, SLIGHT CHANCE OF THUNDERSTORMS.
MONDAY: WINDS LESS THAN 25 KT. CHANCE OF RAIN SHOWERS.
BOX WATCHES/WARNINGS/ADVISORIES
CT...HEAT ADVISORY FROM NOON TODAY TO 8 PM EDT FRIDAY FOR
CTZ002>004.
MA...HEAT ADVISORY FROM NOON TODAY TO 8 PM EDT FRIDAY FOR MAZ002-
003-008>011.
AIR QUALITY ALERT FROM 11 AM THIS MORNING TO 8 PM EDT THIS
EVENING FOR MAZ013-016>024.
RI...AIR QUALITY ALERT FROM 11 AM THIS MORNING TO 8 PM EDT THIS
EVENING FOR RIZ001>008.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
ANZ254>256.
DISCUSSION...MCMINN
AVIATION...MCMINN
MARINE...MCMINN
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