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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBOX 242030
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
430 PM EDT FRI MAY 24 2013

.SYNOPSIS...
A COLD FRONT WILL MOVE SLOWLY ACROSS NEW ENGLAND TODAY WITH MUCH
COOLER AIR BEHIND THE FRONT. LOW PRESSURE WILL DEVELOP ON THIS
FRONT...CAUSING SCATTERED SHOWERS TO LINGER ACROSS THE REGION
THROUGH THIS WEEKEND. CONDITIONS WILL IMPROVE MONDAY. DRY WEATHER
AND SEASONABLE TEMPS ARE EXPECTED INTO THE MIDDLE OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
230 PM UPDATE...

A BROKEN LINE OF SHOWERS HAS DEVELOPED ALONG THE COLD FRONT ACROSS
EASTERN CT/NW RI INTO METRO WEST BOSTON. TEMPS IN THE L70S ALONG
WITH DEW PTS IN THE MU60S ACROSS THIS AREA HAS RESULTED IN SB
CAPES OF AROUND 500 J/KG. DESPITE MODEST DEEP LAYER SHEAR MID
LEVEL LAPSE RATES ARE WEAK SO NOT EXPECTING MUCH IN THE WAY OF
DEEP CONVECTION...JUST SOME HEAVY SHOWERS ACROSS EASTERN MA/RI AND
EASTERN CT.

FOR THE REMAINDER OF THE REGION COMMA HEAD RAINS WILL CONTINUE TO
BLOSSOM ACROSS NY/PA/NJ AND NYC WILL CONTINUE TO SLOWLY PIVOT NE
INTO WESTERN NEW ENGLAND LATER TODAY.

COLD FRONT WILL CONTINUE TO OOZE EASTWARD INTO EASTERN MA LATE
THIS AFTERNOON/EARLY EVENING. BEHIND THE FRONT GUSTY WNW WINDS
WITH THE INITIAL SURGE OF COOL AIR...THEN RELAXING A BIT.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
A DEVELOPING LOW-PRESSURE JUST EAST OF MA THIS EVENING IS NOT
EXPECTED TO MAKE MUCH PROGRESS AWAY FROM OUR REGION. HOWEVER...AS
THIS LOW DEVELOPS A DRY SLOT IS EXPECTED TO BRIEFLY CUT BACK ON
THE COVERAGE OF RAINFALL TOWARD THE EAST COAST. MAIN DEFORMATION
AND FRONTOGENESIS ZONES SHIFT INLAND AS WELL.

SEASONABLE TEMPERATURES FORECAST. A BLEND OF THE MAV/MET GUIDANCE
HANDLES THIS WELL.

&&

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
-- Changed Discussion --
HIGHLIGHTS...

* UPPER LEVEL SYSTEM WILL KEEP SHOWERS AND COOLER TEMPS FOR THE
  WEEKEND.
* IMPROVEMENTS BEGIN ON MONDAY WITH MODERATING TEMPS THROUGH THE MID
  WEEK.
* WARM FRONT BY END OF THE WEEK WILL PUSH TEMPS WELL ABOVE AVERAGE.

OVERVIEW AND MODEL PREFERENCES...


CONFIDENCE LEVEL/MODEL GUIDANCE...MODERATE CONFIDENCE IN THE
OVERALL FORECAST. MODEL GUIDANCE HAS SEEM TO GET ITS ACT TOGETHER
AND HAVE A BETTER HANDLE ON THE NORTHERN STREAM SHORTWAVE AND ITS
PHASING WITH THE UPPER LEVEL TROUGH. APPEARS THAT THE 00Z GFS HAS
GOOD RUN TO RUN CONSISTENCY AND IS SUPPORTED BY SEVERAL OTHER
MODELS...INCLUDING THE 00Z EC. HAVE TRENDED THE FORECAST TO A
BLEND OF THE NAM AND GFS AND GFS/EC FOR THE EXTENDED PORTION.
OVERALL HAVE HIGH CONFIDENCE OF RAIN AND COOLER TEMPS FOR THIS
WEEKEND AND DRYING CONDITIONS FOR MONDAY. LOW CONFIDENCE ON EXACT
TIMING OF PRECIP AND THUNDER POTENTIAL. MODERATE CONFIDENCE FOR
NEXT WEEK...WITH DRY WEATHER AND SEASONABLE TEMPS FOR MID WEEK.
APPEARS A WARM FRONT WILL TRY TO LIFT JUMPING TEMPS WELL ABOVE
AVERAGE...HAVE MODERATE CONFIDENCE.

DETAILS...

THE WEEKEND...

PRECIP/QPF...COLD AND WET HOLIDAY WEEKEND IS IN STORE FOR
SOUTHERN NEW ENGLAND. THE ONLY REGION WHICH MAY HAVE SOME HOPE IS
THE CAPE/ISLANDS AND PERHAPS EASTERN MASS...WHERE DRY AIR WILL TRY
TO PUNCH THROUGH. UPPER LEVEL TROUGH WILL PUSH OVER THE REGION AND
PINWHEEL OVER SOUTHERN NEW ENGLAND TIL SUNDAY BEFORE PUSHING
NORTHWARD. SURFACE LOW OVER CAPE COD CANAL WILL PUSH EASTWARD OF
THE NORTH SHORE. THIS MAY ALLOW FOR SLIGHTLY WARMER TEMPS AND
DRIER CONDITIONS FOR THE CAPE ON SATURDAY AS DRY AIR INTRUSION
WILL PUSH THROUGH AS LOW PRESSURE UNDERGOES CYCLOGENESIS. APPEARS
THAT A GOOD WRAP AROUND OF RAIN ON THE BACK SIDE OF THE LOW WILL
DEVELOP OVER THE CT VALLEY AND DROP OVER AN INCH TO PERHAPS 2
INCHES OF PRECIP FOR THE WEEKEND IN THIS REGION...MAY NEED TO
WATCH FOR POSSIBLE RIVER FLOODING AS THERE HAVE BEEN SEVERAL
INCHES ALREADY FALLEN OVER THE PAST 24 HRS...WITH MORE ON THE WAY.
SURFACE LOW WILL GET PUSHED MORE NORTHWARD INTO THE GULF OF
MAINE...THIS WILL PUSH PRECIP FARTHER EAST AND NORTHWARD ON SUNDAY
AND SLOWLY DISSIPATE FROM SOUTH TO NORTH SUNDAY NIGHT. MAY BE A
TAD SLOW ON TIMING OF PRECIP YET HAVE LOW CONFIDENCE ON THE EXACT
EXIT TIMING.

THUNDER...THERE IS A LOW PROBABILITY OF THUNDER FOR SATURDAY AND
INTO SUNDAY. HOWEVER INCLUDED AN ISOLATED CHANCE AS TOTAL TOTALS
REACH ABOVE 50 AND SURFACE LIS DO DROP TO NEAR 0. APPEARS THAT THE
POTENTIAL IS THERE ESP ACROSS THE EASTERN HALF OF THE REGION ON
SATURDAY THANKS TO THE DRY AIR ALLOWING FOR SOME DIURNAL HEATING
TO BREAK THROUGH. DO NOT ANTICIPATE ANYTHING TO BE STRONG OR
SEVERE. HOWEVER WITH IT BEING A HOLIDAY WEEKEND WANTED TO FOCUS ON
THAT THE POTENTIAL IS THERE.

TEMPERATURES...AS UPPER LEVEL LOW DROPS OVER SOUTHERN NEW
ENGLAND...A COLD POOL WILL SET UP ALLOWING FOR TEMPS TO DROP WELL
BELOW AVERAGE. EXPECT HIGHS TO STRUGGLE TO REACH INTO THE 60S ON
SATURDAY AND THE MID 60S ON SUNDAY. LOWS OVERNIGHT DO GET QUITE
CHILLY...IN THE MID TO UPPER 30S.


MONDAY AND WEDNESDAY...

MONDAY IS A TRANSITION DAY FROM THE SOGGY COOL WEEKEND TO A
WARM...DRY MID-WEEK. UPPER LEVEL LOW WILL CONTINUE TO PUSH OFF SHORE
INTO THE GULF OF MAINE...ALLOWING FOR MIDWEST RIDGE TO BUILD.
SURFACE HIGH PRESSURE WILL SLIDE OVER AND HELP KEEP A DRY FORECAST
FOR MOST OF THE WORK WEEK. HOWEVER CANNOT RULE OUT A SPOT SHOWER OR
TWO...ESP IF SEA BREEZES DEVELOPS. TEMPS WILL INCREASE THROUGH THE
MID-WEEK...WITH UPPER 60S FOR MONDAY TO UPPER 70S BY WEDNESDAY.

THURSDAY...
MOTHER NATURE IS TRYING TO MAKE UP FOR THE COLD/RAINY WEEKEND BY
BRING A STRONG WARM FRONT TO SOUTHERN NEW ENGLAND BY LATE WEEK.
THIS WARM FRONT WILL BRING MUGGY CONDITIONS AND A CHANCE OS
ISOLATED SHOWERS. HOWEVER MAIN THINK TO WATCH IS MAX TEMPS...WHICH
MAY REACH THE MID 80S. SOME MODELS EVEN PUSH THE REGION INTO THE
90S. SINCE THIS IS SEVERAL DAYS AWAY...KEEP IN MIND THAT MOTHER
NATURE MAY CHANGE HER MIND.
-- End Changed Discussion --

&&

.AVIATION /20Z FRIDAY 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 TONIGHT AND SAT.

THROUGH 00Z...
COLD FRONT AND WIND SHIFT FROM SSW TO WNW WILL SLOWLY ADVANCE
EASTWARD INTO EASTERN MA LATE TODAY. SCATTERED SHOWERS WITH
ISOLATED HEAVIER RAINS ACROSS RI AND EASTERN MA. RISK OF TSTMS IS
VERY LOW. CIGS WERE AN EVEN BLEND OF METNAM AND NAM12 GUID WHILE
VSBYS WERE A 50/50 BLEND OF MET AND MAV GUID. IFR CONFINED TO
SOUTHEAST MA WITH MVFR ELSEWHERE.

AFTER 00Z...
COLD FRONT OVER EASTERN MA WILL DRIFT JUST OFFSHORE WITH ALL
TERMINALS HAVING A WIND SHIFT TO THE WNW. SCATTERED SHOWERS ACROSS
EASTERN NEW ENGLAND WITH MORE WIDESPREAD RAINS WESTERN NEW
ENGLAND. IFR CONFINED TO SOUTHEAST MA WITH MVFR ELSEWHERE.

SAT...
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.

KBOS TERMINAL...WIND SHIFT FROM SOUTH TO WEST-NORTHWEST BETWEEN
19Z-20Z. SCATTERED SHOWERS MAINLY IN MVFR. SAT...SHOWERS BECOME
MORE WIDESPREAD DURING THE AFTERNOON AND WINDS INCREASE UP TO 25
KT.

KBDL TERMINAL...SCATTERED SHOWERS THIS EVENING BECOME MORE
WIDESPREAD TONIGHT AND SATURDAY. MAINLY MVFR CONDITIONS. WNW WINDS
UP TO 25 KT TONIGHT AND POSSIBLY UP TO 30 KT SAT WITH MVFR
CONTINUING.

OUTLOOK...SATURDAY NIGHT THROUGH WEDNESDAY...

SATURDAY NIGHT-SUNDAY...LOW TO MODERATE CONFIDENCE. UNSETTLED
PATTERN WITH VARIABLE CONDITIONS FROM VFR TO MVFR-IFR CONDITIONS
IN SHRA/FOG. LOW PROB OF ISOLD TSTM SAT NIGHT. PRECIP TAPERS OFF
FROM S-N DURING SUNDAY WITH GENERAL VFR CONDITIONS BY LATE SUNDAY
THOUGH VFR CIGS LINGER SUNDAY NIGHT. MAY SEE PATCHY MVFR-IFR VSBYS
IN PATCHY FOG SUN NIGHT.

MONDAY-TUESDAY...HIGH CONFIDENCE. VFR. LOW CONFIDENCE ON SEA
BREEZE DEVELOPMENT. MAY SEE PATCHY FOG WITH MVFR-IFR VSBYS LATE
MON NIGHT-EARLY TUE MORNING.

WEDNESDAY...MODERATE 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.

11 AM UPDATE...

STRONG SSW WINDS BEGINNING TO PULL AWAY FROM EASTERN MA WATERS AT
LATE MORNING. LIGHTER SSW WINDS TO FOLLOW BUT THEN AN ABRUPT WIND
SHIFT TO THE WEST LATE TODAY FROM WEST TO EAST. AREAS OF DENSE FOG
WILL IMPACT THE RI AND SOUTHERN MA WATERS TODAY BUT THEN IMPROVE
WITH THE WIND SHIFT.

HIGH CONFIDENCE TODAY.

A LOW-LEVEL JET AND MODERATE TO HEAVY RAINFALL WILL BRING NEAR 25
KT GUSTS ON THE WATERS EARLY THIS MORNING. A STRONG LOW-LEVEL
INVERSION WILL LIMIT GUSTS...SO GALES NOT EXPECTED. PERSISTENT SW
FLOW WILL RESULT IN BUILDING SEAS TODAY. WINDS WILL DIMINISH LATER
TODAY AS THIS LOW-LEVEL JET DEPARTS. EXPECTING LOW VSBYS IN FOG
AND LOCALLY HEAVY SHOWERS. ISOLATED THUNDERSTORMS ARE ALSO
POSSIBLE.

TONIGHT...MODERATE CONFIDENCE. A LOW PRES AND COLD FRONT WILL
LIKELY STALL ACROSS THE EASTERN NEAR-SHORE WATERS. WIND DIRECTIONS
WILL BE QUITE DIFFERENT DEPENDING UPON WHERE THIS FRONT SETS UP
EXACTLY. SOUTH WINDS SHOULD CONTINUE TO DIMINISH...BEFORE
REINTENSIFYING FROM THE NORTH BEHIND THIS LOW PRESSURE. LOW
PROBABILITY FOR THUNDERSTORMS. AREAS OF LOW VSBYS IN HEAVIER
SHOWERS AND PATCHY FOG. SEAS WILL REMAIN 5 FT OR HIGHER...MAINLY
ACROSS THE OPEN WATERS.

OUTLOOK...SATURDAY NIGHT THROUGH WEDNESDAY...

MODERATE CONFIDENCE THROUGH THE PERIOD.

SATURDAY NIGHT-SUNDAY...SURFACE LOW WILL LINGER ACROSS THE EASTERN
WATERS SAT NIGHT...THEN SHIFT SLOWLY NE SUN. SEAS REMAINING ABOVE
5 FT. W-NW WINDS WILL PICK UP...WITH GUSTS UP TO GALE FORCE MAINLY
ON THE SOUTHERN WATERS TO S AND E OF NANTUCKET. KEPT GALE WATCH
GOING THERE. WINDS SHOULD DIMINISH DURING SUN AFTERNOON/NIGHT.

MONDAY...WINDS DIMINISH BELOW SMALL CRAFT. SEAS REMAIN AOA 5 FT
ON THE OUTER WATERS.

TUESDAY...WINDS AND SEAS REMAIN BELOW SMALL CRAFT.

WEDNESDAY...S-SE WINDS MAY SEE SE WINDS PICK UP DURING THE DAY WITH
GUSTS UP TO 20 KT. SEAS MAY APPROACH 5 FT ON THE SOUTHERN WATERS.
-- End Changed Discussion --

&&

.TIDES/COASTAL FLOODING...
EAST COAST OF MA THIS WEEKEND...
ASTRONOMICAL HIGH TIDES WILL OCCUR THIS WEEKEND INTO EARLY NEXT
WEEK. WITH A SURFACE LOW LINGERING JUST OFF THE SOUTHERN NEW
ENGLAND EAST COAST SATURDAY INTO SUNDAY...EXPECTING GUSTY
NORTHERLY TO NORTHWEST WINDS ESPECIALLY DURING THE DAYTIMES HOURS.
AT BOSTON...A HIGH TIDE OF 11.9FT WILL OCCUR TONIGHT AT 11:21 PM
AND 12.2 FT EARLY SUNDAY MORNING AT 12:12 AM. EXPECTING LIGHT
SOUTHERLY WINDS DURING TODAY/S DAYTIME HIGH TIDE...SO THIS IS LESS
OF A CONCERN. LOOKING AT THE SUNDAY MORNING HIGH TIDE...NORTHERLY
TO NORTHWESTERLY WINDS MAY HELP INCREASE THE SURGE ESPECIALLY FOR
CAPE COD BAY. RIGHT NOW ONLY EXPECTING MINOR SPLASHOVER ACROSS
NORTH-FACING BEACHES. WILL NEED TO CONTINUE TO MONITOR AND UPDATE
WITH THE LATEST FORECAST GUIDANCE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...GALE WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY MORNING
     FOR ANZ235-237-254>256.
     SMALL CRAFT ADVISORY UNTIL 2 PM EDT SATURDAY FOR ANZ235-237-
     250-254>256.
-- End Changed Discussion --

&&

$$
SYNOPSIS...NOCERA/EVT
NEAR TERM...NOCERA
SHORT TERM...NOCERA
LONG TERM...EVT
AVIATION...NOCERA/EVT
MARINE...NOCERA/EVT
TIDES/COASTAL FLOODING...NOCERA