217
FXUS61 KBOX 061853
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
ISSUED BY NATIONAL WEATHER SERVICE GRAY ME
253 PM EDT TUE MAY 6 2025
SYNOPSIS
PERIODS OF LIGHT TO MODERATE RAIN WILL CONTINUE TODAY.
WEDNESDAY IS TRENDING DRIER, WITH ONLY ISOLATED SHOWERS AND
THUNDERSTORMS. APPEARS WE MAY BRIEFLY DRY OUT BY THURSDAY BEFORE
MORE RAIN ARRIVES ON FRIDAY INTO SATURDAY.
NEAR TERM /THROUGH TONIGHT/
TODAY
ANOTHER DREARY AND RAINY DAY AS AN UPPER LEVEL CLOSED TROUGH
OVER THE OHIO RIVER VALLEY SENDS MULTIPLE ROUNDS OF SHORTWAVE
ENERGY INTO SNE. NO MAJOR CHANGES IN QPF AMOUNTS FROM GUIDANCE
OVERNIGHT, STILL EXPECTING A WIDE 1-2 INCHES OF RAIN THROUGH
TODAY. WITH ESE WINDS, THE EAST SLOPES OF THE BERKS, WORCESTER
HILLS, AND NW RI COULD SEE LOCALLY HIGHER AMOUNTS OF UP TO 2.5
INCHES DUE TO UPSLOPING EFFECTS. THE MAIN FLOODING IMPACTS
CONTINUE TO BE RIVER FLOODING, WITH SEVERAL GAUGES NEARING THE
ACTION OR MINOR FLOOD STAGES. WILL ALLOW THE FLOOD WATCH TO
CONTINUE AS PLANNED AS THERE MAY STILL BE MINOR/NUISANCE STREET
FLOODING TODAY AS RAIN RATES COULD EXCEED 0.25 INCHES PER HOUR.
WITH WARM SOUTHERLY FLOW TODAY, HIGH TEMPERATURES WILL REACH THE
UPPER 60S TO LOW 70S.
SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/
TONIGHT
THE DRY SLOT MOVES IN TONIGHT, ALLOWING RAIN TO SCATTER OUT
FROM WEST TO EAST. WITH AN ABUNDANCE OF LEFTOVER LOW-LEVEL
MOISTURE, EXPECT LOW STATUS, FOG, AND DRIZZLE TO FILL IN,
ESPECIALLY NEAR COASTAL AREAS. LOW TEMPERATURES STAY MILD ONCE
AGAIN IN THE LOW TO MID-50S.
WEDNESDAY
LATEST GUIDANCE HAS SPED UP THE UPPER LEVEL CLOSED LOW AND COLD
POOL, EXITING PRIOR TO PEAK HEATING. THE RAPID DEAMPLIFICATION
OF THE TROUGH ALSO BRINGS THE 500MB COLD POOL FURTHER NORTH.
THESE FACTORS HAVE GREATLY DIMINISHED THE CONVECTIVE
THUNDERSTORM RISK, WITH THE BEST CHANCE NOW BEING ACROSS EASTERN
MA WHERE HREF MEANS SBCAPE STILL REACHES 500 J/KG. DECREASING
CLOUDS IN THE AFTERNOON WILL ALLOW HIGH TEMPERATURES TO REACH
THE LOW TO MID-70S.
LONG TERM /THURSDAY THROUGH MONDAY/
KEY POINTS
* BRIEF DRY AND MILD WEATHER FOR A CHANGE THURS
* LOOKING UNSETTLED WITH RAIN LIKELY, ALTHOUGH THE DETAILS STILL
ARE UNCERTAIN.
THURSDAY:
THURS LOOKS TO BE THE ONLY RELATIVELY DRY DAY IN THE WORKWEEK,
WITH WEAK SFC RIDGING AND MOSTLY SUNNY TO PARTLY CLOUDY
CONDITIONS. HIGHS COULD REACH MORE SEASONABLE LEVELS IN THE MID
60S TO MID 70S, HOWEVER CLOUDS THEN START TO INCREASE AGAIN FOR
THURS NIGHT.
FRIDAY INTO THE WEEKEND:
PREDICTABILITY IN THE DETAILS THEN DWINDLES WITH PRETTY LARGE
DIFFERENCES IN THE GUIDANCE STILL CONTINUING. WHAT'S REASONABLY
AGREED UPON IS ANOTHER TROUGH OR UPPER LEVEL LOW AGAIN LEADING
TO ANOTHER PERIOD OF UNSETTLED WEATHER, BUT IT REMAINS UNCERTAIN
WHERE SURFACE LOW PRESSURE SETS UP RELATIVE TO SOUTHERN NEW
ENGLAND, EITHER THROUGH THE INTERIOR OR OFFSHORE. IT STANDS TO
BE AGAIN QUITE UNSETTLED, BUT UNTIL THERE'S A BIT MORE
CONSISTENCY, IT'S DIFFICULT TO REALLY PINPOINT MORE SPECIFICS
SHORT OF IT BEING A LIKELY WET WEATHER PATTERN WITH COOLER THAN
NORMAL TEMPS.
AVIATION /18Z TUESDAY THROUGH SATURDAY/
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
18Z TAF UPDATE:
THROUGH 00Z WEDNESDAY: MODERATE CONFIDENCE.
MAINLY IFR-LIFR FOR MOST AIRPORTS IN MIST/FOG, STRATUS AND
PERIODS OF LIGHT SHOWERS. A ROUND OF STEADIER SHRA/POSSIBLE TS
NOW OVER LONG ISLAND/SOUTHERN CT TO LIFT ENE BETWEEN 19-22Z WITH
3-5SM VISBY. MAINLY SE WINDS AROUND 10 KT; EXCEPT BOS/BED WHERE
NE WINDS TO TURN ESE/SE WITH THE APPROACH/PASSAGE OF LINE OF
SHOWERS/EMBEDDED TS.
TONIGHT: MODERATE CONFIDENCE.
AREAS IFR EARLY MAY TREND CLOSER TO MVFR/VFR, HOWEVER ANY
BREAKS IN CLOUD COVER COULD LEAVE AREAS PRONE TO MVFR-LIFR
RADIATIONAL BR/FG WITH BETTER CHANCE FOR INTERIOR TAFS. S WINDS
AROUND 5-10 KT.
WEDNESDAY: MODERATE CONFIDENCE.
SHOULD SEE CONDITIONS TREND TO VFR EARLY WED IF THEY HAVE NOT
ALREADY DONE SO. AFTER 17Z, MAY SEE SCT LOW-TOPPED SHRA/TS
DEVELOP MAINLY ALONG/NORTH OF THE MASS PIKE WITH BRIEF/TEMPORARY
RESTRICTIONS PSBL. S TO SW WINDS AROUND 10 KT.
WEDNESDAY NIGHT: HIGH CONFIDENCE.
VFR. WILL HAVE MONITOR FOR PATCHY FOG GIVEN DAMP CONDITIONS LAST
COUPLE DAYS AS SKIES CLEAR OUT BUT NOT A SURE THING.
KBOS TAF...MODERATE CONFIDENCE.
KBDL TAF...MODERATE CONFIDENCE.
OUTLOOK /THURSDAY THROUGH SATURDAY/...
WEDNESDAY NIGHT: VFR.
THURSDAY: MAINLY VFR, WITH LOCAL MVFR POSSIBLE. SLIGHT CHANCE
SHRA.
THURSDAY NIGHT: MAINLY VFR, WITH LOCAL IFR POSSIBLE. CHANCE
SHRA.
FRIDAY: MVFR/IFR CONDITIONS POSSIBLE. SHRA LIKELY, ISOLATED
TSRA.
FRIDAY NIGHT: MAINLY VFR, WITH AREAS IFR POSSIBLE. CHANCE SHRA.
SATURDAY: MAINLY VFR, WITH LOCAL IFR POSSIBLE. SLIGHT CHANCE
SHRA.
MARINE
FORECASTER CONFIDENCE LEVELS:
LOW - LESS THAN 30 PERCENT.
MEDIUM - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
TODAY THROUGH WEDNESDAY: HIGH CONFIDENCE.
WINDS FLIP ESE TODAY AT 20-25 KNOTS. SEAS RISE TO 3-5 FEET. LOW
CLOUDS, FOG, AND DRIZZLE WILL LIKELY PERSIST TODAY AND TONIGHT
WITH PERIODS OF OFF AND ON SHOWERS AND PERHAPS A RUMBLE OR TWO
OF THUNDER. WINDS TURN MORE SSW WEDNESDAY, BUT REMAIN UNDER 20
KNOTS. LOW CHANCE FOR AN ISOLATED THUNDERSTORM ENTERING THE NEAR
SHORE WATERS NEAR THE EAST COAST ON WEDNESDAY
OUTLOOK /THURSDAY THROUGH SATURDAY/...
WEDNESDAY NIGHT: WINDS LESS THAN 25 KT. SEAS UP TO 5 FT. PATCHY
FOG.
THURSDAY: WINDS LESS THAN 25 KT. AREAS OF SEAS APPROACHING
5 FT.
THURSDAY NIGHT: WINDS LESS THAN 25 KT. SEAS UP TO 5 FT. CHANCE
OF RAIN SHOWERS.
FRIDAY: WINDS LESS THAN 25 KT. SEAS UP TO 5 FT. RAIN SHOWERS
LIKELY, ISOLATED THUNDERSTORMS.
FRIDAY NIGHT: WINDS LESS THAN 25 KT. SEAS UP TO 5 FT. CHANCE OF
RAIN SHOWERS.
SATURDAY: WINDS LESS THAN 25 KT. SEAS UP TO 5 FT. SLIGHT CHANCE
OF RAIN SHOWERS.
HYDROLOGY
245 PM UPDATE:
FLOOD WATCH CONTINUES IN EFFECT UNTIL 8 PM FOR WESTERN AND
CENTRAL MA. SOME AREAS IN CT AND WESTERN MA SAW RAIN TOTALS IN
THE 3-4 INCH RANGE OVERNIGHT. ANOTHER ROUND OF SHOWERS AND
EMBEDDED THUNDERSTORMS WILL MOVE THROUGH SOUTHERN NEW ENGLAND
DURING THE MID TO LATE-AFTERNOON HOURS. ALTHOUGH RAIN AMTS
SHOULD NOT PROVE SUBSTANTIAL WITH THIS PASSING SHOWERS, MOST
AREAS ARE PRETTY SATURATED IN THE FLOOD WATCH AREA SUCH THAT
LEAVING IT UP SEEMS TO BE THE BEST COURSE OF ACTION, THEN COULD
BE DROPPED UPON CESSATION OF RAINS.
SEVERAL RIVERS AND TRIBS TIED TO THE CT RIVER ARE SWOLLEN FROM
YESTERDAY'S RAINS, AND MANY GAGES ARE STILL EXPERIENCING AT
LEAST MODEST RISES. WE'VE ISSUED A RIVER FLOOD WARNING FOR THE
CT RIVER AT HARTFORD, WHICH IS EXPECTED TO RISE INTO FLOOD STAGE
AROUND MIDNIGHT IN RESPONSE TO THE AFOREMENTIONED RAINS WORKING
THROUGH THE BASIN. WE ARE ALSO MONITORING THE CT RIVER AT
MIDDLE HADDAM, WHICH IS FORECAST TO RISE INTO FLOOD STAGE
TOMORROW AFTERNOON.
BOX WATCHES/WARNINGS/ADVISORIES
CT...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR CTZ002>004.
MA...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR MAZ002>004-008>012.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EDT WEDNESDAY FOR ANZ235-237.
SMALL CRAFT ADVISORY UNTIL 8 PM EDT WEDNESDAY FOR ANZ254>256.
SYNOPSIS...LOCONTO
NEAR TERM...LOCONTO
SHORT TERM...LOCONTO
LONG TERM...LOCONTO
AVIATION...LOCONTO
MARINE...LOCONTO
HYDROLOGY...LOCONTO
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