138
FXUS61 KBOX 220703
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
303 AM EDT WED APR 22 2026
WHAT HAS CHANGED
SHOWER COVERAGE TODAY NOW LOOKS MORE INTERMITTENT WITH SEVERAL
PERIODS OF DRIER WEATHER AT TIMES. ALTHOUGH SOME THREAT FOR
ISOLATED SHOWERS SHOULD EXIST THURSDAY IN EASTERN MA AND RI,
LESS INSTABILITY PROBABLY LIMITS THE RISK FOR ANY
THUNDERSHOWERS.
KEY MESSAGES
- OVERCAST TODAY WITH INTERMITTENT SHOWERS TO DODGE, BUT WITH
SEVERAL PERIODS OF DRY WEATHER IN BETWEEN.
- PARTLY TO MOSTLY CLOUDY WITH ISOLATED AFTERNOON SHOWERS
THURSDAY, MAINLY IN EASTERN NEW ENGLAND, BUT TURNING DRIER,
COOL AND BLUSTERY LATER IN THE DAY.
- DRY WEATHER TO GOVERN OUR WEATHER PATTERN LATE IN THE WEEK
INTO EARLY NEXT WEEK, WITH ONSHORE FLOW AND COOLER THAN NORMAL
TEMPERATURES.
DISCUSSION
KEY MESSAGE 1...OVERCAST TODAY WITH INTERMITTENT SHOWERS TO DODGE,
BUT WITH SEVERAL PERIODS OF DRY WEATHER IN BETWEEN.
WEAK-AMPLITUDE 500 MB SHORTWAVE DISTURBANCE AND ASSOCIATED POORLY-
ORGANIZED LOW PRESSURE NEAR EASTERN MI/SOUTHERN ON IS SPREADING A
CANOPY OF MID-LEVEL CLOUDINESS OUR WAY EARLY THIS MORNING. DUE IN
PART TO PRETTY WEAK FORCING AND DRIER AIR TO ITS EAST, REALLY NOT A
HEALTHY LOOK TO THE CHARACTER OF THE PRECIPITATION SHIELD ACROSS
EASTERN NY AND SW CT AND IT SEEMS UNLIKELY TO IMPROVE VERY MUCH AS
IT MOVES EASTWARD INTO SOUTHERN NEW ENGLAND THRU THE MORNING HOURS.
I PHRASED WEATHER IN THE ZONE FORECAST AS ISOLATED TO SCATTERED RAIN
SHOWERS, BUT THERE WILL LIKELY BE SEVERAL PERIODS OF DRY WEATHER IN
BETWEEN THESE SHOWERS AND THOSE THAT DO FALL ARE REALLY OF HARDLY
ANY IMPACT AT ALL. ANY OUTDOOR PLANS SHOULD BE GENERALLY OKAY BUT
THERE COULD BE SOME PASSING SHOWERS TO DODGE. THE BEST CHANCE FOR
MORE PERSISTENT SHOWER COVERAGE IN IN CT AND RI AND THE SOUTHERN
COASTAL WATERS AS THE FEATURE MOVES SOUTHWARD. EVEN AS SPOTTY
SHOWERS COME TO AN END...IT LOOKS AS THOUGH LOWERING CLOUD CEILINGS
TAKES PLACE WITH QUITE A BIT OF LOW-LEVEL RH TAKING HOLD FOR
TONIGHT. EVEN IF SHOWERS AREN'T AS PERSISTENT - AND IT IS LOOKING
LIKE THAT ENDS UP BEING THE CASE - OVERCAST CONDITIONS SHOULD KEEP
TEMPS TODAY ONLY IN THE MID TO UPPER 40S, AND PROBABLY NOT FALLING
VERY MUCH UNDER OVERCAST.
KEY MESSAGE 2...PARTLY TO MOSTLY CLOUDY WITH ISOLATED AFTERNOON
SHOWERS THURSDAY, MAINLY IN EASTERN NEW ENGLAND, BUT TURNING DRIER,
COOL AND BLUSTERY LATER IN THE DAY.
TOUGH FORECAST FOR THURSDAY AS A CLOSED UPPER LOW TO OUR NORTH AND
EAST DUE TO DOWNSTREAM NORTH ATLANTIC BLOCKING DRIVES A COMPACT,
FAST-MOVING DISTURBANCE IN NW FLOW SOUTHEASTWARD FROM NORTHERN
QUEBEC. THIS WILL DRIVE A SURFACE LOW OVER NH/ME AND AN ASSOCIATED
COLD FRONT SOUTHEASTWARD INTO EASTERN SECTIONS OF MA AND RI DURING
THE AFTERNOON. SOME HIGH-RES GUIDANCE AND THE 00Z GFS DEPICT
ISOLATED CONVECTIVE SHOWERS ALONG THE FRONTAL BOUNDARY INTO EASTERN
MA AND RI DURING THE MIDAFTERNOON, DRIVEN BY COLD PROFILES ALOFT
(WBZ HEIGHTS OF AROUND 4000 FT AGL). COMPARED TO YESTERDAY'S
GUIDANCE, INSTABILITY VALUES ARE NOT AS HIGH EVEN IN THE MORE
BULLISH NAM AND THAT COULD BE BECAUSE MOSTLY CLOUDY CONDITIONS
CARRYING OVER FROM THE OVERNIGHT COULD PRECEDE ITS ARRIVAL AND
TEMPER SURFACE HEATING TO AN EXTENT. CALLED IT ISOLATED SHOWERS BUT
ANY SHOWERS COULD BE CAPABLE OF GRAUPEL AS THEY RACE SOUTHEASTWARD.
FRONTAL PASSAGE WILL BE MARKED BY CLEARING SKIES AND A WINDSHIFT TO
NW AROUND 10-15 MPH WITH GUSTS 20-25 MPH, TO GO ALONG WITH RAPIDLY
FALLING DEWPOINTS THROUGH THE UPPER 20S. THIS BRINGS RELATIVE
HUMIDITIES DOWN TO AROUND 30 TO 35 PERCENT; THE COMBO OF RHS AT THIS
RANGE AND THE NORTHWEST BREEZES WOULD LEND THEMSELVES TO POSSIBLE
FIRE WEATHER CONCERNS, BUT THOSE CONDITIONS PROBABLY OVERLAP FOR A
COUPLE/FEW HOURS BEFORE SUNDOWN AND IT IS ALSO DEBATABLE HOW
RECEPTIVE FUELS MIGHT BE. LATER SHIFTS COULD REACH OUT TO THE FIRE
WEATHER PARTNERS FOR THEIR INPUT, BUT METEOROLOGICAL CONDITIONS
COULD BE MORE BORDERLINE THAN PORTIONS OF WESTERN NEW ENGLAND/NEW
YORK, AND ESPECIALLY SO IF WE DO GET POP-UP SHOWERS. HIGHS 50S TO
LOWER 60S.
KEY MESSAGE 3...DRY WEATHER TO GOVERN OUR WEATHER PATTERN LATE IN
THE WEEK INTO EARLY NEXT WEEK, WITH ONSHORE FLOW AND COOLER THAN
NORMAL TEMPERATURES.
CLOSED-OFF UPPER CIRCULATION OVER THE MARITIMES ASSOCIATED WITH A
SLOW-TO-EVOLVE NORTH ATLANTIC BLOCKING REGIME WILL GOVERN OUR
WEATHER PATTERN FRIDAY THROUGH THE WEEKEND, THEN BECOMES REPLACED BY
SHORTWAVE RIDGING INTO EARLY NEXT WEEK.
COLDER POCKET OF AIR ALOFT WILL KEEP TEMPERATURES ON THE COOLER SIDE
OF NORMAL THROUGH THE WEEKEND WITH AN ONSHORE FLOW AS SFC RIDGING
TAKES HOLD. EXPECT HIGHS IN THE 50S, WITH UPPER 50S/LOW 60S WESTERN
NEW ENGLAND AND LOWS IN THE MID 30S TO MID 40S. ALTHOUGH SOME OF THE
GLOBAL GUIDANCE AND ENSEMBLE MEMBERS TRIES TO BRING A PRECIP SHIELD
INTO FAR WESTERN/SOUTHWESTERN PORTIONS OF SOUTHERN NEW ENGLAND LATER
SAT INTO PART OF SUN, COMBO OF ANTECEDENT DRY AIR IN PLACE WITH MID-
LEVEL CONFLUENT FLOW FROM THE CLOSED LOW WOULD SEEM MORE LIKELY TO
SUPPRESS ANY PRECIP TO OUR SOUTH AND WEST. SO WHILE IT'S A GENERALLY
COOLER PERIOD, ALL-IN-ALL SHAPING UP TO BE A DRIER WEEKEND. DRY
WEATHER CONTINUES INTO EARLY NEXT WEEK TOO, WITH INDICATIONS
FOR A WARMING TREND AS GEOPOTENTIAL HEIGHTS RISE.
AVIATION /06Z WEDNESDAY THROUGH SUNDAY/
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
06Z TAF UPDATE: HIGH CONFIDENCE.
THROUGH TODAY: MODERATE CONFIDENCE.
WEAK LOW PRESSURE BRINGS INTERMITTENT -SHRA WITH UNRESTRICTED
VISIBILITY THROUGH TODAY. BEST CHANCE OF STEADIER SHOWERS MAINLY
FOR BDL-PVD SOUTH AND EAST, WITH SPOTTY/VCSH TYPE COVERAGE
NORTH AND EAST.
CEILING HEIGHT GUIDANCE HAS BEEN POOR AND HAS OVERDONE THE
EXTENT OF SUB-VFR ACROSS EASTERN NY WITH MANY AREAS STILL OVC
VFR, WHICH REDUCES FORECAST CONFIDENCE. EVEN IN SHRA/VCSH,
THINKING OVC MAINLY VFR CEILINGS PROBABLY PREVAIL UNTIL AT LEAST
18Z. CEILINGS SHOULD THEN START TO DETERIORATE TOWARD MVFR FROM
WEST TO EAST LATER THIS AFTERNOON AS SHOWERS END, BUT BETTER
POTENTIAL FOR LOWEST CEILINGS (MVFR/IFR) TONIGHT. SOUTH WINDS
INCREASING TO AROUND 10 KT, WITH OCCASIONAL GUSTS TO 20 KT THRU
MIDAFTERNOON BEFORE WEAKENING TO AROUND 5-10 KT BY LATE IN THE
DAY.
TONIGHT: MODERATE CONFIDENCE.
CEILINGS DETERIORATE TO MVFR/IFR, WHICH SHOULD CONTINUE INTO THE
PRE-DAWN THURSDAY HOURS. UNCERTAIN IF WE SEE AREAS OF MIST/FOG
BUT COULD BE POSSIBLE. WINDS GO LIGHT SOUTHEAST.
THURSDAY: HIGH CONFIDENCE.
SUB-VFR CEILINGS CONTINUE EARLY BUT SHOULD BEGIN TO LIFT/SCATTER
TO VFR BASES WITH WINDS BECOMING WSW 5-10 KT. ISOLATED SHRA OR
EVEN POSSIBLE TS FOR EASTERN MA/RI AIRPORTS DURING THE
MIDAFTERNOON. WINDS THEN SHIFT NW AND INCREASE TO 10-13 KT WITH
GUSTS 22-25 KT LATE IN THE DAY.
KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. OVC MAINLY VFR
CEILINGS WITH INTERMITTENT -SHRA (LEFT AS VCSH) 14-20Z. ANY
SHOWERS THEN COME TO AN END, BUT WITH IT BRINGS BETTER
POTENTIAL FOR CEILINGS TO DROP TO MVFR AND EVENTUALLY TO IFR
LEVELS OVERNIGHT. S WINDS AROUND 10-12 KT WITH GUSTS AROUND 20
KT, EASING TONIGHT WHILE BECOMING LIGHT SE.
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF. OVC MAINLY VFR
CEILINGS WITH INTERMITTENT -SHRA 08-18Z. ANY SHOWERS THEN END
AFTER 18Z, BUT BETTER POTENTIAL FOR CEILINGS TO DROP TO MVFR
LATE IN THE DAY AND EVENTUALLY TO IFR LEVELS OVERNIGHT. S WINDS
AROUND 10 KT, EASING TONIGHT WHILE BECOMING LIGHT SE.
OUTLOOK /THURSDAY THROUGH SUNDAY/...
THURSDAY: MAINLY VFR, WITH LOCAL MVFR POSSIBLE. BREEZY.
ISOLATED SHRA.
THURSDAY NIGHT THROUGH SUNDAY: VFR.
MARINE
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
HIGH CONFIDENCE THROUGH THE WEEKEND.
WINDS AND SEAS REMAIN BELOW SCA LEVELS THROUGH THE WEEKEND.
WEAK LOW PRESSURE PASSES SOUTH OF NEW ENGLAND TODAY, BRINGING
MOSTLY INTERMITTENT SHOWERS. SOUTHERLY WINDS AROUND 10-15 KT
WITH GUSTS TO 20KT AND WITH 3-4 FT SEAS. A BRIEF PERIOD OF NW
BREEZES TAKES HOLD THURSDAY AFTERNOON WITH PERHAPS BORDERLINE
SCA GUSTS FOR A FEW HOURS, BUT PROBABLY MARGINAL ENOUGH FOR NO
HEADLINES. ISOLATED SHOWERS/POSSIBLE ROGUE THUNDERSHOWER
POSSIBLE THURSDAY AFTERNOON IN EASTERN WATERS.
LIGHT ONSHORE WINDS AND CALM SEAS WILL PREVAIL INTO THE WEEKEND
AS HIGH PRESSURE REMAINS NEAR MARITIMES AND A SERIES OF LOW
PRESSURE SYSTEMS TRACK WEST AND SOUTH OF NEW ENGLAND.
OUTLOOK /THURSDAY THROUGH SUNDAY/...
THURSDAY: WINDS LESS THAN 25 KT. ISOLATED RAIN SHOWERS.
THURSDAY NIGHT THROUGH SATURDAY NIGHT: WINDS LESS THAN 25 KT.
SUNDAY: WINDS LESS THAN 25 KT. SEAS LOCALLY APPROACHING 5 FT.
BOX WATCHES/WARNINGS/ADVISORIES
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.
DISCUSSION...LOCONTO
AVIATION...LOCONTO
MARINE...LOCONTO
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