782
FXUS61 KBOX 150547
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
147 AM EDT FRI MAY 15 2026
WHAT HAS CHANGED
NO SIGNIFICANT CHANGES MADE WITH THIS UPDATE.
KEY MESSAGES
- RAIN CONTINUES EASTWARD THIS AFTERNOON AND EVENING BEFORE
CLEARING FOR MOST EARLY TONIGHT. DREARY AGAIN FRIDAY.
- WARMER TEMPERATURES FOR THE WEEKEND INTO NEXT WEEK, WITH
MOSTLY DRY WEATHER.
- POTENTIAL FOR THUNDERSTORMS RETURNS TUE/WED, A FEW OF WHICH
COULD BE STRONG TO SEVERE.
DISCUSSION
KEY MESSAGE 1...RAIN CONTINUES EASTWARD THIS AFTERNOON AND EVENING
BEFORE CLEARING FOR MOST EARLY TONIGHT. DREARY AGAIN FRIDAY.
RAIN CURRENTLY OVER CENTRAL MA, RI, AND EASTERN CT WILL SLOWLY
CONTINUE EAST AND NORTH THIS AFTERNOON AND EVENING AHEAD OF AN
OCCLUDED FRONT PUSHING THROUGH SOUTHERN NEW ENGLAND. GUIDANCE
INDICATES THE MOISTURE PLUME FROM THE SOUTH HELPING FUEL THIS
RAINFALL HAS PWAT VALUES BETWEEN 1-1.25", WITH THE HIGHER VALUES
FURTHER TO THE EAST ALONG THE COAST AND OVER CAPE COD AND THE
ISLANDS. WITH REGARDS TO THE CHANCES FOR SOME EMBEDDED THUNDER LATER
THIS EVENING, THE CHANCES ARE STILL LOW, BUT LATEST MESOANALYSIS
DOES HAVE SOME POCKETS OF INSTABILITY OVER EASTERN MA. SO,
OCCASIONAL RUMBLES OF THUNDER CANNOT BE COMPLETELY RULED OUT.
RAINFALL TOTALS EXPECTED TO RANGE BETWEEN 0.5" TO 1.5"; HIGHER
TOTALS ARE MOST LIKELY IN NORTHERN MA, WITH SOUTHERN RI SEEING
THE LOWER END OF THE SCALE. ELSEWHERE ACROSS THE REGION, TOTALS
AROUND 0.75-1.00" ARE MORE LIKELY. LOWS TONIGHT WILL LIKELY BE
IN THE MID TO UPPER 40S.
RAIN WILL TAPER OFF AND BECOME MORE OF A DRIZZLE TONIGHT, LIKELY
SOMETIME BEFORE MIDNIGHT, AS A SURFACE LOW PASSES RIGHT OVER
SOUTHERN NEW ENGLAND BEHIND THE FRONT. THIS FEATURE WILL ALSO AID IN
THE RETURN OF ONSHORE FLOW. NE WINDS ARE EXPECTED TO CONTINUE
THROUGH FRIDAY, LIMITING THE CHANCE FOR ANY SIGNIFICANT IMPROVEMENTS
TO CLOUD COVER. THE ASSOCIATED UPPER LEVEL LOW THAT'S CURRENTLY
CENTERED OVER LAKE ONTARIO WILL MOVE IN OVERHEAD, AND WITH IT,
COOLER TEMPERATURES ALOFT THROUGH THE COLUMN. 950 MB TEMPERATURES
AROUND 6-8C TOMORROW AFTERNOON COMBINED WITH THE PERSISTENT CLOUD
COVER WILL LIKELY KEEP HIGH TEMPERATURES IN THE 50S.
KEY MESSAGE 2...WARMER TEMPERATURES FOR THE WEEKEND INTO NEXT
WEEK, WITH MOSTLY DRY WEATHER.
A MUCH IMPROVED FORECAST AS WE HEAD INTO THE WEEKEND AND MID LEVEL
HEIGHTS WILL FINALLY BE ON THE RISE AS A MARGINAL RIDGING/ZONAL
PATTERN MOVES IN FOR THE WEEKEND. THIS W/SW FLOW ADVECTS A MUCH
WARMER AIRMASS OVERHEAD AT 850 MB TEMPS RISE FROM 3C FRIDAY TO 12C
OVER THE WEEKEND AND THEN SURGING TO NEAR 18C BY TUESDAY/WEDNESDAY.
THE RESULT WILL BE A STRETCH OF WARM WEATHER THIS WEEKEND, THEN
HIGHLY ANOMALOUS WARMTH BY TUESDAY. HIGH TEMPERATURES ON SATURDAY
WILL SIT COMFORTABLY IN THE 70S, WITH UPPER 70S MORE LIKELY SUNDAY
AND MONDAY, PEAKING ON TUESDAY WITH POTENTIAL FOR WIDESPREAD 80S.
THIS, WITH DEWPOINTS SURGING WELL INTO THE 60S MAY MAKE FOR A BIT OF
A MUGGY DAY.
KEY MESSAGE 3...POTENTIAL FOR THUNDERSTORMS RETURNS TUE/WED, A
FEW OF WHICH COULD BE STRONG TO SEVERE.
AS PREVIOUSLY MENTIONED, DEWPOINTS ARE EXPECTED TO SURGE INTO THE
60S ON TUESDAY AND THIS TOGETHER WITH TEMPS IN THE 80S WILL
CONTRIBUTE TO >1000 J/KG OF SURFACE BASED CAPE WITH LOW LEVEL LAPSE
RATES OF 8-9C/KM. LOTS OF INSTABILITY, BUT THE MISSING PIECE IS A
GOOD FORCING MECHANISM AS THE COLD FRONT UNTIL LATER WED OR WED
NIGHT. THAT BEING SAID, THERE ARE SIGNS OF ENOUGH OF A KINK IN THE
LOW LEVEL FLOW THAT THERE COULD BE ENOUGH CONVERGENCE TO KICK OFF
SOME STORMS. LACK OF BULK SHEAR AND POOR ML LAPSE RATES WOULD LIMIT
VERTICAL GROWTH AND HOW STRONG ANY STORMS COULD GET BUT CSU AND NSSL
MACHINE LEARNING GUIDANCE BOTH HIGHLIGHT TUESDAY WITH A POSSIBILITY
OF SOME SEVERE STORMS. STAY TUNED.
AVIATION /06Z FRIDAY THROUGH TUESDAY/
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
06Z TAF UPDATE:
THROUGH 12Z FRIDAY: MODERATE CONFIDENCE.
LOWEST CATEGORIES (IFR-LIFR) DUE TO STRATUS AND MIST/FOG FOR
EASTERN/NORTHERN MA AND RI. LOW-END VFR TO PERIODS MVFR CEILINGS
FOR ORH AND BDL WITH NO VISBY RESTRICTIONS. THESE GENERAL
TRENDS SHOULD CONTINUE THROUGH 12Z FRIDAY, ALTHOUGH FOG COVERAGE
SHOULD EXPAND A BIT FURTHER NORTH AND EAST. HOWEVER BETTER
MOISTURE SUPPORTIVE OF -RA IS CONFINED WELL TO THE NORTH SO
SHOULD BE LARGELY DRY. LIGHT MAINLY WNW WINDS BUT COULD TURN
CALM FOR A WHILE.
TODAY: MODERATE CONFIDENCE.
IFR-LIFR STRATUS/FOG FOR EASTERN/NORTHEAST MA AND RI REMAINS,
ALTHOUGH VISBYS COULD IMPROVE TOWARD 3-6 SM RANGE. MVFR CEILINGS
TO EVENTUALLY FILL BACK INTO BDL AND ORH THRU THIS MORNING.
WINDS EVENTUALLY TURN NE 6-10 KT, MORE LIKELY AROUND ~13-15Z IN
FAR NORTHEAST MA AND THEN GRADUALLY BUILDING SOUTHWARD THROUGH
~17-19Z. THAT PROBABLY BRINGS THE BEST CHANCE AT DRIZZLE OR
LIGHT RAIN SHOWERS TOO; ONE SECONDARY AREA TO WATCH FOR POP-UP
SHOWERS IS ALONG THE SOUTH COAST IN THE AFTERNOON. GRADUAL
CLEARING FROM NORTH TO SOUTH TOWARD MVFR/PERHAPS SPOT VFR LEVELS
AFTER 22Z, AS WINDS TURN LIGHT N/NW.
TONIGHT: HIGH CONFIDENCE IN TRENDS, BUT MODERATE ON FOG
DEVELOPMENT.
PERIOD OF CLEARING TAKES PLACE 00-03Z SAT WITH AT LEAST BRIEF
VFR. HOWEVER MVFR- IFR PATCHY FOG COULD DEVELOP UPON CLEARING, GIVEN
RECENT DAMP GROUND, LIGHT WINDS AND A LIKELIHOOD OF NARROW
TEMPERATURE/DEWPOINT SPREADS. IT IS UNCERTAIN IF FOG DEVELOPS
AND ITS AREAL COVERAGE, BUT MOST TAFS SEEM PRONE TO FOG
DEVELOPMENT BESIDES THE USUAL FOG TROUBLE SPOTS. LIGHT NORTHERLY
WINDS, WHICH SHIFT TO SW 5 KT OR LESS BY DAYBREAK.
SATURDAY: HIGH CONFIDENCE.
ANY MIST OR FOG FROM OVERNIGHT DISSIPATES RAPIDLY AFTER SUNRISE
TO VFR CONDITIONS. SW WINDS INCREASE TO AROUND 10-13 KT WITH
GUSTS IN THE 20-25 KT RANGE.
KBOS...MODERATE CONFIDENCE IN TAF. IFR CEILINGS WITH NW WINDS
AROUND 5-8 KT. WINDS TO FLIP TO NE AROUND 14-16Z WHICH BRINGS
BETTER CHANCE AT EITHER -DZ OR LIGHT -SHRA THRU 22Z. WINDS THEN
FLIP TO LIGHT NORTHERLY AFTER 22-00Z. POSSIBLE MIST/FOG FOR
FRIDAY NIGHT.
KBDL...MODERATE CONFIDENCE IN TAF. LOW END VFR CEILINGS TO TREND
TO MVFR 09-13Z, WITH NORTH/NORTHEAST WINDS 5-10 KT. CEILINGS
THEN SCATTER TO VFR LEVELS LATE THIS AFTERNOON, BUT CLEARING
COULD BRING A RISK FOR POSSIBLE MIST/FOG FRIDAY NIGHT.
OUTLOOK /SATURDAY THROUGH TUESDAY/...
SATURDAY THROUGH SUNDAY: VFR. BREEZY.
SUNDAY NIGHT THROUGH MONDAY NIGHT: VFR.
TUESDAY: VFR. BREEZY.
MARINE
FORECASTER CONFIDENCE LEVELS...
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
SE TO E WINDS AROUND 10-15 KT THROUGH THE REST OF TODAY, BUT
EASTERLY SWELL INCREASES WAVE HEIGHTS TO AROUND 4-7 FT TONIGHT
AND CONTINUE INTO FRIDAY. SMALL CRAFT ADVISORIES HAVE BEEN
ISSUED TO ACCOUNT FOR THE RISING SEAS. RAIN WITH EMBEDDED
DOWNPOURS CONTINUE THROUGH THIS AFTERNOON AND EVENING, WITH
MORE INTERMITTENT SHOWERS, DRIZZLE AND FOG FOR TONIGHT INTO
FRIDAY.
WINDS REMAIN GENERALLY BELOW 15 KT FOR FRIDAY NIGHT. SEAS WILL
START TO DIMINISH FRIDAY NIGHT AS A COASTAL LOW WELL OFFSHORE
CONTINUES PULLING AWAY, THOUGH SMALL CRAFT ADVISORIES MAY NEED
TO CONTINUE THROUGH THE OVERNIGHT HOURS THEN.
OUTLOOK /SATURDAY THROUGH TUESDAY/...
SATURDAY THROUGH SATURDAY NIGHT: LOW RISK FOR SMALL CRAFT
ADVISORY WINDS WITH GUSTS UP TO 25 KT. SEAS UP TO 5 FT.
SUNDAY THROUGH TUESDAY: WINDS LESS THAN 25 KT. AREAS OF SEAS
APPROACHING 5 FT.
BOX WATCHES/WARNINGS/ADVISORIES
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EDT SATURDAY FOR ANZ235-237-
251.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT SATURDAY FOR ANZ250-
254>256.
DISCUSSION...BW/HRENCECIN
AVIATION...LOCONTO
MARINE...BW/HRENCECIN
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