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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBOX 250759
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
359 AM EDT SAT MAY 25 2013

.SYNOPSIS...
-- Changed Discussion --
A LOW PRESSURE JUST OFF THE COAST WILL SLOWLY MOVE NORTH THROUGH
TONIGHT. SOME IMPROVEMENT IS LIKELY SUNDAY AS THIS LOW DEPARTS
INTO NORTHERN NEW ENGLAND. MAINLY DRY WEATHER IS ANTICIPATED WITH
MODERATING TEMPS MONDAY INTO TUESDAY. A WARM FRONT WILL MOVE
THROUGH WEDNESDAY BRINGING SOME SHOWERS AND THUNDER. EXPECT WARM
AND MUGGY CONDITIONS BY THE END OF THE WORK WEEK.
-- End Changed Discussion --

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
25/00Z MODELS HAVE COME INTO VERY GOOD AGREEMENT WITH THEIR
HANDLING OF THE SYNOPTIC FEATURES. AS SUCH...USED A GENERAL MODEL
COMPROMISE TO HANDLE THE TIMING.

OVERALL...EXPECTING A LOW PRESSURE OVER MASSACHUSETTS BAY TO STAY
NEARLY STATIONARY TODAY. THIS WILL GENERATE PERIODS OF SHOWERS
ACROSS SOUTHERN NEW ENGLAND...AS WELL AS MAINTAINING DECENT COLD
AIR ADVECTION. HIGH TEMPERATURES TODAY ARE NOT EXPECTED TO BE MUCH
HIGHER THAN OUR NORMAL LOW TEMPERATURES. FOR SOME HIGHER
LOCATIONS...HIGH TEMPERATURES TODAY MAY ACTUALLY BE LOWER THAN THE
NORMAL LOW TEMPERATURE.

HEIGHTS ALOFT CONTINUE TO FALL WHICH RESULTS IN COOLING FROM THE
TOP DOWN. VERY IMPRESSIVE SYNOPTIC SCALE FORCING VIA MID LEVEL
Q-VECTOR CONVERGENCE. STRONGEST LIFT WILL ONCE AGAIN BE ACROSS
WESTERN SECTIONS OF CT/MA INTO SOUTHWEST NH...CENTERED AROUND THE
I-91 CORRIDOR. MODEL SOUNDINGS SUGGEST LATE IN THE DAY ACROSS
THIS AREA ESPECIALLY THE HIGHER TERRAIN OF MA/NH THAT RAIN MAY MIX
OR CHANGE TO SNOW AT TIMES WHEN PRECIPITATION INTENSITY IS
GREATEST. THIS WILL BE MOST COMMON AT ELEVATIONS GREATER THAN 1000
FT AS FREEZING LEVELS DROP TO THIS LEVEL. SURFACE AND GROUND
TEMPERATURES LIKELY TOO WARM FOR ANY ACCUMULATION BUT MINOR SNOW
ACCUMULATION POSSIBLE ON TREES/POWERLINES. DON/T EXPECT ANY IMPACT
JUST SOME DECORATIVE SNOW POSSIBLE HIGHER TERRAIN.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
A MID-LEVEL LOW WILL MOVE SLIGHTLY NORTHEAST TODAY...WHICH WILL
PLACE SOUTHERN NEW ENGLAND WELL INTO THE CORE OF COLDER AIR ALOFT
OVERNIGHT. THIS WILL CONTINUE THE POSSIBILITY FOR MIXED RAIN/SNOW
SHOWERS ACROSS THE HIGHER TERRAIN. LOW TEMPERATURES ARE EXPECTED
TO BE 10 TO 15 DEGS BELOW SEASONAL NORMALS.

AS FOR ANY CONVECTION...HAVE REMOVED MENTION FOR NOW BUT WOULD NOT
BE SURPRISED TO HEAR A FEW ISOLD RUMBLES AS PRECIP AND UPPER LEVEL
SYSTEM START TO SHIFT NE.

ON SUNDAY...LEFTOVER SHOWERS WILL END FROM S-N DURING THE DAY.
CLOUDS WILL REMAIN FOR MOST OF THE DAY AS NORTHWEST WINDS PICK
UP. EXPECTING GUSTS UP TO 30-35 MPH...ESPECIALLY ACROSS CENTRAL
AND WESTERN AREAS. WILL REMAIN COOL WITH HIGHS AGAIN 10-15 DEGREES
BELOW NORMAL.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...

-- Changed Discussion --
HIGHLIGHTS...

* IMPROVEMENTS ON MONDAY WITH MODERATING TEMPS THROUGH THE MID WEEK.
* WARM FRONT MID-WEEK WILL BRING AROUND OF SHOWERS AND THUNDER.
* MUGGY AND WELL ABOVE AVG CONDITIONS RETURN BY THURS.

CONFIDENCE LEVEL/MODEL GUIDANCE...

HIGH CONFIDENCE IN PRECIPITATION FORECAST...MODERATE CONFIDENCE ON
EXACT TIMING. DUE TO UNCERTAINTY IN AMPLIFICATION OF THE RIDGE BY
END OF NEXT WEEK...HAVE MODERATE CONFIDENCE ON TEMPS. MODELS ARE IN
FAIRLY GOOD AGREEMENT WITH THIS RUN SHOWING A UPPER-LEVEL TROUGH
PUSHING INTO THE WESTERN CONUS...WHILE A STRONG AMPLIFIED RIDGE
MOVES OVER THE EASTERN USA. MODELS ARE STRUGGLING WITH HOW MUCH THE
HEIGHTS BUILD BY THE END OF NEXT WEEK. THEREFORE HAVE LEANED WITH
WPC THINKING FOR THE FORECAST AND THE ENSEMBLE MEANS FOR DAYS 6 AND
7.

DETAILS...

MONDAY AND TUESDAY...
UPPER LEVEL TROUGH WILL EJECT EASTWARD AS A RIDGE BUILDS OVER THE
MIDWEST. THE SURFACE LOW WHICH BROUGHT RAIN AND COOL TEMPS WILL BE
WELL IN THE GULF OF MAINE ALLOWING FOR DRYING CONDITIONS AND SUNNY
SKIES. AM CONCERNED ABOUT SUN NIGHT TEMPS...MAY BE TO WARM AS
WINDS DECREASE AND SKIES CLEAR...FROST MAY BE A POSSIBILITY ESP IN
THE NW ZONES. OTHERWISE EXPECT A PLEASANT MEMORIAL DAY WITH TEMPS
REACHING INTO THE LOW TO MID 70S AND SUNNY SKIES. TUESDAY WILL BE
A REPEAT BUT WITH TEMPS WARMING INTO THE MID 70S THANKS TO A MORE
SOUTHERLY WIND COMPONET. COOLER ALONG THE COAST AS SEA BREEZES
DEVELOP.

WEDNESDAY...
UPPER LEVEL RIDGE WILL GLIDE EASTWARD ON WEDNESDAY...HOWEVER A
FEW RIPPLES IN THE FLOW WILL PUSH A WARM FRONT OVER NEW ENGLAND.
EXPECT SHOWERS TO DEVELOP BY WEDNESDAY AND LASTING INTO EARLY
THURSDAY MORNING. CONVECTION PARAMETERS POINT TO THUNDERSTORM
DEVELOP ALONG THE FRONT SO CONTINUED THE MENTIONING OF THUNDER.
TEMPS WILL REACH THE MID TO UPPER 70S.

THURSDAY INTO FRIDAY...
ONCE THE WARM FRONT PUSHES THROUGH WARM AND MUGGY CONDITIONS
RETURN TO SOUTHERN NEW ENGLAND. CANNOT RULE OUT A SPOT SHOWERS
SINCE THE REGION WILL BE IN THE WARM SECTOR. HOWEVER MAIN ISSUE TO
WATCH IS THE MAX TEMPS...WHICH MAY REACH THE MID 80S. SOME MODELS
EVEN PUSH THE REGION INTO THE 90S. SINCE THIS IS SEVERAL DAYS AWAY
WILL CONTINUE TO BE MODEST AND KEEP TEMPS INTO THE MID TO LOW 80S.
-- End Changed Discussion --


&&

.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

OVERVIEW...MODERATE CONFIDENCE INTO TONIGHT.

TODAY...WIDESPREAD SHOWERS OVER WESTERN NEW ENGLAND PIVOTS INTO
EASTERN NEW ENGLAND DURING THE AFTERNOON. SNOW MAY MIX IN WITH THE
RAIN ACROSS THE HIGHER TERRAIN OF WESTERN MA AND SOUTHWEST NH. NW
WINDS MAY GUSTS TO 25 KT. IFR CONFINED TO SOUTHEAST MA WITH MVFR
ELSEWHERE. TIMING OF PRECIPITATION...AND THE DECREASE OF
VISIBILITY...VERY DIFFICULT TO TIME EXACTLY. TAFS WERE MORE OF AN
OVERALL EXPECTATION OF CONDITIONS WITHIN SHOWERS. VISIBILITY
SHOULD BE BETTER OUTSIDE OF SHOWERS.

TONIGHT-SUNDAY...MODERATE CONFIDENCE. UNSETTLED PATTERN WITH
VARIABLE CONDITIONS FROM VFR TO MVFR-IFR CONDITIONS IN SHRA/FOG.
LOW PROB OF ISOLD TSTM TONIGHT. PRECIPITATION TAPERS OFF FROM S-N
DURING SUNDAY WITH GENERAL VFR CONDITIONS BY LATE SUNDAY.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.

OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...

MONDAY INTO TUESDAY...HIGH CONFIDENCE. VFR. MODERATE CONFIDENCE ON
SEA BREEZE DEVELOPMENT.

WEDNESDAY...MODERATED CONFIDENCE. MAINLY VFR. MAY SEE CLOUDS/SCT
SHOWERS MOVE IN AHEAD OF WARM FRONT WITH LOCAL MVFR CONDITIONS.
-- End Changed Discussion --

&&

.MARINE...
-- Changed Discussion --
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

TODAY...LOW PRES TRACKS FROM NANTUCKET TO GULF OF MAINE. NW WINDS
UP TO 25 KT POSSIBLE ALONG WITH LINGERING S SWELLS SOUTH WATERS OF
RI AND MA. SHOWERS REDUCE VSBY AS WELL.

TONIGHT-SUNDAY...SURFACE LOW WILL LINGER ACROSS THE EASTERN
WATERS TONIGHT...THEN SHIFT SLOWLY NE SUNDAY. SEAS REMAINING
ABOVE 5 FT. W-NW WINDS WILL PICK UP...WITH GUSTS UP TO GALE FORCE
MAINLY ACROSS THE SOUTHERN WATERS TO S AND E OF NANTUCKET. WINDS
SHOULD DIMINISH DURING SUNDAY AFTERNOON.

OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...

MONDAY AND TUESDAY...HIGH CONFIDENCE. SEAS WILL SLOWLY DIMINISH. WIND
GUSTS ON MONDAY MAY REACH CLOSE TO 25KTS ESP ACROSS THE SOUTHERN
WATERS. OTHERWISE GOOD BOATING WEATHER ON TUESDAY.

WEDNESDAY...MODERATE CONFIDENCE. SOUTHERLY WINDS WILL PICK UP
DURING THE DAY WITH GUSTS UP TO 20-25 KT. SEAS WILL BE ABOVE 5 FT.
A SCA MAY BE NEEDED.
-- End Changed Discussion --

&&

.HYDROLOGY...
WHILE THERE MAY BE PERIODIC HEAVIER RAIN SHOWERS ACROSS SOUTHERN
NEW ENGLAND TODAY INTO EARLY SUNDAY...NOT THINKING IT WILL BE
PERSISTENT ENOUGH TO RESULT IN FLOODING. WILL HAVE TO MONITOR THE
POSSIBILITY OF TRAINING CELLS THOUGH. NO HEADLINES PLANNED AT THIS
TIME.

&&

.TIDES/COASTAL FLOODING...
EAST COAST OF MA THIS WEEKEND...

HIGH ASTRONOMICAL TIDES THIS WEEKEND. AT BOSTON...A HIGH TIDE OF
12.2 FT EARLY SUNDAY MORNING AT 12:12 AM. ESTOFS INDICATING UP TO
0.7 FT SURGE WHICH SEEMS REASONABLE. DESPITE THE LACK OF MUCH
WAVE ACTION COULD SEE SOME MINOR INUNDATION. AT THE TYPICALLY
PRONE LOCATIONS OF EASTERN MA. CONFIDENCE NOT HIGH ENOUGH TO
ISSUE A COASTAL FLOOD ADVISORY ESPECIALLY GIVEN A MARGINAL EVENT.
LATER SHIFTS WILL HAVE TO REEVALUATE THIS RISK.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 6 PM EDT
     SUNDAY FOR ANZ232>234-236.
     SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO NOON EDT SUNDAY
     FOR ANZ230.
     GALE WARNING FROM 2 PM THIS AFTERNOON TO 7 AM EDT SUNDAY FOR
     ANZ235-237.
     SMALL CRAFT ADVISORY UNTIL NOON EDT SUNDAY FOR ANZ250.
     SMALL CRAFT ADVISORY UNTIL NOON EDT SUNDAY FOR ANZ251.
     GALE WARNING FROM 2 PM THIS AFTERNOON TO 11 AM EDT SUNDAY FOR
     ANZ254>256.
-- End Changed Discussion --

&&

$$
SYNOPSIS...BELK/DUNTEN
NEAR TERM...BELK
SHORT TERM...BELK
LONG TERM...DUNTEN
AVIATION...BELK/DUNTEN
MARINE...BELK/DUNTEN
HYDROLOGY...
TIDES/COASTAL FLOODING...