362
FXUS61 KBOX 032328
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
728 PM EDT FRI JUL 3 2026
WHAT HAS CHANGED
NO SIGNIFICANT CHANGES TO THE FORECAST.
KEY MESSAGES
- DANGEROUS HEATWAVE CONTINUES THROUGH THIS AFTERNOON AND
INDEPENDENCE DAY. HEAT INDICES OF 100-110 DEGREES EXPECTED
THIS AFTERNOON, AND 95-100+ ON INDEPENDENCE DAY.
- A WELCOMED BREAK FROM THE HEAT WITH COOLER AND MORE
SEASONABLE TEMPERATURES RETURNING FOR THE FIRST HALF OF NEXT
WEEK. THERE IS ALSO SOME LOW CONFIDENCE POTENTIAL FOR SOME
MUCH NEED RAIN MAY OCCUR IN THE LATE SUNDAY THOUGH TUESDAY
TIME FRAME.
DISCUSSION
KEY MESSAGE 1...DANGEROUS HEATWAVE CONTINUES THROUGH THIS
AFTERNOON AND INDEPENDENCE DAY. HEAT INDICES OF 100-110 DEGREES
EXPECTED THIS AFTERNOON, AND 95-100+ ON INDEPENDENCE DAY.
STOUT SUMMER RIDGE CONTINUES TO SPIN OVER THE CAROLINAS AND VA.
DANGEROUS HEAT IS ONGOING ACROSS NEW ENGLAND. HOURLY METAR
OBSERVATION AT KBOS REGISTERED A TEMPERATURE OF 100F AT 2:54 PM
EDT, MARKING TWO CONSECUTIVE DAYS OF TRIPLE DIGITS.
HEAT INDICES ACROSS THE REGION ARE HANGING WELL IN THE 100-110
RANGE. EXTREME HEAT WARNING CONTINUES UNTIL 8 PM EDT SATURDAY
FOR ALL OF SOUTHERN NEW ENGLAND EXCEPT FOR THE CAPE/ISLANDS
(HEAT ADVISORY IN THOSE PARTS). HEAT INDICES SATURDAY WILL RANGE
FROM 95F TO AT OR ABOVE 100F DURING THE AFTERNOON.
MEANWHILE, ISOLATED TO SCATTERED CONVECTION IS POPPING UP OVER
WESTERN AND SOUTHERN NY. THESE STORMS MAY TRY TO MAKE THEIR WAY
INTO WESTERN MA LATE THIS EVENING INTO THE OVERNIGHT HOURS, BUT
IT'LL GET HARDER AFTER SUNSET WITH INSTABILITY DROPPING OFF.
CONVECTION CHANCES LOOK SLIGHTLY BETTER SATURDAY AFTERNOON AND
EVENING WITH A COLD FRONT APPROACHING, BUT GUIDANCE HAS COME
DOWN ON THE COVERAGE WITH EACH FORECAST UPDATE, SO THIS MAY NOT
BE AS MUCH OF AN ISSUE AS ONCE THOUGHT. GOOD NEWS FOR
INDEPENDENCE DAY FESTIVITIES. STAY COOL AND HYDRATED!
KEY MESSAGE 2...A WELCOMED BREAK FROM THE HEAT WITH COOLER AND
MORE SEASONABLE TEMPERATURES RETURNING FOR THE FIRST HALF OF
NEXT WEEK. THERE IS ALSO SOME LOW CONFIDENCE POTENTIAL FOR SOME
MUCH NEED RAIN MAY OCCUR IN THE LATE SUNDAY THOUGH TUESDAY TIME
FRAME.
THERE IS HIGH CONFIDENCE THAT TEMPS WILL COOL DOWN AND RETURN
TO MORE SEASONABLE READINGS THRU THE MIDDLE OF NEXT WEEK. SOME
OF THAT IS DUE TO MODELED CLOUD COVER AND RAIN, BUT EVEN IN THE
ABSENCE OF THOSE FACTORS 850 MB TEMPS AROUND +15C WOULD GIVE
SURFACE TEMPS IN THE 80S RATHER THAN THE 90S TO 100 DEGREES WE
HAVE BEEN SEEING. IN ADDITION THERE IS PRETTY GOOD CONSENSUS
THAT DEWPOINTS MAY EVEN FALL BACK INTO THE 50S FOR SOME PARTS OF
THE WORCESTER HILLS AND MERRIMACK VALLEY. SO OVERALL MUCH MORE
COMFORTABLE TEMPS ARE FORECAST IN THE EXTENDED.
THE RAINFALL CHANCES ON THE OTHER HAND REMAIN UNCERTAIN. THERE
IS GROWING ENSEMBLE SUPPORT FOR AT LEAST A WIDESPREAD LIGHT RAIN
EVENT, WHICH IS MUCH NEEDED. THE NBM 10TH PERCENTILE QPF IS
STILL ZERO FOR THE FORECAST AREA, BUT 25TH PERCENTILE VALUES
HAVE CLIMBED TO 0.10 TO 0.05 INCHES FROM SOUTHWEST TO NORTHEAST.
75TH PERCENTILE QPF HAS ALSO INCREASED TO NEAR 1 INCH, MAINLY
ACROSS WESTERN MASS. SO I DON'T FEEL THAT LIKELY TO CATEGORICAL
POP IS UNREASONABLE AT THIS TIME. THERE DOES APPEAR TO BE A BIT
OF A BIMODAL STRUCTURE WITH QPF ACROSS ENSEMBLE GUIDANCE. ONE
LESS THAN 0.50 INCHES, AND ANOTHER AT OR ABOVE 1 INCH. AROUND
BDL ABOUT 25 PERCENT OF MEMBERS ARE GREATER THAN 1 INCH QPF, VS
AROUND 15 PERCENT AS YOU MOVE TOWARDS LWM. IT IS ALSO NOTABLE
THAT MANY OF THESE RAINY MEMBER ARE FROM THE ECMWF ENSEMBLE.
THAT'S WHY I'M LEANING MORE LIGHT RAIN AT THIS TIME THAN A TRUE
SOAKER.
AVIATION /00Z SATURDAY THROUGH WEDNESDAY/
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
00Z TAF UPDATE...
TODAY THROUGH INDEPENDENCE DAY...HIGH CONFIDENCE.
VFR CONDITIONS CONTINUE TO DOMINATE THROUGH INDEPENDENCE DAY.
HI-RES WOFS GUIDANCE SUGGESTS ANY SHRA/TSRA KEEPS SOUTHWEST OF
THE FORECAST AREA THIS EVENING. THERE IS A LOW CHANCE THAT SOME
CONVECTION CAN HOLD TOGETHER OUT OF THE LAKE ONTARIO AREA SO I
WILL MAINTAIN THE PROB30 FOR TSRA AT BDL AND SHRA AT ORH.
OTHERWISE SHRA/TSRA WILL BE A THREAT AGAIN ON INDEPENDENCE DAY
FOR SOUTHWESTERN PORTIONS OF THE FORECAST AREA. GIVEN THAT IT IS
A MAINLY CT THREAT I WILL ALSO KEEP THE SECOND PROB30 AT BDL FOR
AFTERNOON EVENING TSRA. MUCH LIKE PREVIOUS NIGHTS IT WILL BE
DIFFICULT TO BRING FOG INTO ACK, ESPECIALLY WITH WINDS TURNING
MORE WESTERLY THAN SOUTHWESTERLY. SO I DO NOT HAVE MENTION IN
THE TAF. WEST NORTHWEST WINDS ON INDEPENDENCE DAY WILL BE GUSTY
AT TIMES, UP TO 20 KNOTS AT THE TERMINALS.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF, UNCERTAINTY IN
THUNDERSTORM POTENTIAL AND TIMING.
OUTLOOK /SATURDAY NIGHT THROUGH WEDNESDAY/...
SUNDAY: VFR. SLIGHT CHANCE SHRA.
SUNDAY NIGHT: VFR. CHANCE SHRA.
MONDAY: MAINLY VFR, WITH LOCAL MVFR POSSIBLE. CHANCE SHRA,
SLIGHT CHANCE TSRA.
MONDAY NIGHT: MVFR/IFR CONDITIONS POSSIBLE. SHRA LIKELY, SLIGHT
CHANCE TSRA.
TUESDAY: VFR. BREEZY. CHANCE SHRA, CHANCE TSRA.
TUESDAY NIGHT: VFR. CHANCE SHRA.
WEDNESDAY: VFR. SLIGHT CHANCE SHRA.
MARINE
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
TODAY THROUGH INDEPENDENCE DAY...HIGH CONFIDENCE.
WINDS/SEAS STILL LOOK TO REMAIN BELOW SMALL CRAFT ADVISORY
THRESHOLDS THIS AFTERNOON THROUGH INDEPENDENCE DAY. HOWEVER,
SOME 20+ KNOT WIND GUSTS NEAR SHORE THIS AFTERNOON WILL RESULT
IN SOME CHOP IN SOME NEAR SHORE SOUNDS AND BAYS. A SIMILAR STORY
IS IN STORE FOR SATURDAY.
OUTLOOK /SATURDAY NIGHT THROUGH WEDNESDAY/...
SUNDAY: WINDS LESS THAN 25 KT. SLIGHT CHANCE OF RAIN SHOWERS.
SUNDAY NIGHT: WINDS LESS THAN 25 KT. CHANCE OF RAIN SHOWERS.
MONDAY: WINDS LESS THAN 25 KT. CHANCE OF RAIN SHOWERS, SLIGHT
CHANCE OF THUNDERSTORMS.
MONDAY NIGHT: WINDS LESS THAN 25 KT. SEAS LOCALLY APPROACHING
5 FT. RAIN SHOWERS LIKELY, CHANCE OF THUNDERSTORMS.
TUESDAY: WINDS LESS THAN 25 KT. AREAS OF SEAS APPROACHING 5 FT.
CHANCE OF RAIN SHOWERS, CHANCE OF THUNDERSTORMS.
TUESDAY NIGHT: WINDS LESS THAN 25 KT. SEAS UP TO 5 FT. CHANCE
OF RAIN SHOWERS, SLIGHT CHANCE OF THUNDERSTORMS.
WEDNESDAY: WINDS LESS THAN 25 KT. SEAS UP TO 5 FT. SLIGHT
CHANCE OF RAIN SHOWERS.
CLIMATE
RECORD HIGH TEMPERATURES:
JULY 3:
KBOS: 102/1911
KBDL: 102/1966
KPVD: 98/2002
KORH: 96/1911
JULY 4:
KBOS: 104/1911
KBDL: 99/1911
KPVD: 99/1919
KORH: 102/1911
RECORD HIGH MINIMUM TEMPERATURES:
JULY 3:
KBOS: 80/2002
KBDL: 73/2018
KPVD: 78/2002
KORH: 72/2002
JULY 4:
KBOS: 77/2002
KBDL: 74/2018
KPVD: 77/2002
KORH: 73/2018
BOX WATCHES/WARNINGS/ADVISORIES
CT...EXTREME HEAT WARNING UNTIL 8 PM EDT SATURDAY FOR CTZ002>004.
MA...EXTREME HEAT WARNING UNTIL 8 PM EDT SATURDAY FOR MAZ002>021-
026.
AIR QUALITY ALERT UNTIL 11 PM EDT THIS EVENING FOR MAZ020>024.
HEAT ADVISORY UNTIL 8 PM EDT SATURDAY FOR MAZ022-023.
RI...EXTREME HEAT WARNING UNTIL 8 PM EDT SATURDAY FOR RIZ001>007.
AIR QUALITY ALERT UNTIL 11 PM EDT THIS EVENING FOR RIZ003-004-
006>008.
MARINE...NONE.
DISCUSSION...BOATMAN/LEGRO
AVIATION...LEGRO
MARINE...BOATMAN
CLIMATE...FT
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page