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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
943 PM EDT TUE OCT 21 2014

.SYNOPSIS...
SCATTERED SHOWERS TONIGHT INTO THE FIRST PART OF WEDNESDAY WILL
TURN INTO A SOAKING RAIN LATER WEDNESDAY INTO EARLY THURSDAY IN
ASSOCIATION WITH A COASTAL LOW PRESSURE SYSTEM. SHOWERS WILL
LINGER FRIDAY AS THE STORM SLOWLY PULLS AWAY FROM NEW ENGLAND.
MAINLY DRY WEATHER EXPECTED THIS WEEKEND WITH SEASONABLE
TEMPERATURES.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...

930 PM UPDATE...

CLUSTER OF HEAVY SHOWERS WITH EMBEDDED THUNDER OVER WESTERN
WORCESTER COUNTY HAS FINALLY DISSIPATED. THUS FLASH FLOOD WARNING
AND FLOOD ADVISORY HAVE BEEN ALLOWED TO EXPIRE. BIG DIFFERENCE
BETWEEN DUAL POL WHICH ESTIMATED A STORM TOTAL OF UP TO 5.9 INCHES
NEAR WARE...WHILE LEGACY MUCH LESS AT 2.9 INCHES. LEGACY MATCHES
UP BETTER WITH SURROUNDING RADARS AND IT PROBABLY MORE ACCURATE
THAN THE DUAL POL GIVEN THE LOW FREEZING LEVEL THIS EVENING /7
KFT/.

AS FOR THE REMAINDER OF THIS EVENING AND OVERNIGHT...WATER VAPOR
IMAGERY INDICATES CLOSED MID LEVEL LOW OVER WESTERN PA WITH
MULTIPLE SHORT WAVES ROTATING AROUND THIS LARGE CIRCULATION. THIS
WILL TRANSLATE TO SCATTERED SHOWERS OVERNIGHT. 00Z UPSTREAM SOUNDING
AT OKX LONG ISLAND INDICATES A VERY DEEP LAYER OF MOIST ADIABATIC
LAPSE RATES. THIS WILL CONTINUE THE RISK OF AN ISOLATED
THUNDERSTORM WITH HEAVY RAIN OVERNIGHT. PREVIOUS FORECAST CAPTURES
THESE NICELY SO NO MAJOR CHANGES WITH THIS UPDATE.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...

***A SOAKING RAIN LATE WEDNESDAY INTO EARLY THURSDAY WITH THE 
  HEAVIEST AMOUNTS EXPECTED ACROSS NORTHEAST MASSACHUSETTS***

WEDNESDAY AND WEDNESDAY NIGHT...

AREAS OF LIGHT RAIN AND SHOWERS WILL CONTINUE TO EXPAND FROM NORTH 
TO SOUTH THROUGH MID AFTERNOON WEDNESDAY...AS MOIST ONSHORE 
NORTHEAST FLOW INCREASES. THE WIDESPREAD SOAKING RAIN WILL WAIT 
UNTIL LATER WEDNESDAY AFTERNOON AND PARTICULARLY WEDNESDAY NIGHT.

THE SOAKING RAIN WILL DEVELOP AS LOW PRESSURE AND ITS ASSOCIATED 
CLOSED MID LEVEL CENTERS LIFTS NORTHEAST.  A STRONG EASTERLY LOW 
LEVEL JET OF 30 TO 40 KNOTS WILL PROVIDE PLENTY OF MOISTURE AND 
STRONG LIFT FOR A WIDESPREAD HEAVY RAIN EVENT.  THE CORE OF THE 
STRONGEST LOW LEVEL JET WILL SETUP ACROSS OUR NORTHEAST 
ZONES...WHICH IS WHERE WE EXPECT THE HEAVIEST RAIN.  OVERALL... 
EXPECT A WIDESPREAD 1 TO 2 INCHES OF RAIN ACROSS MOST OF OUR REGION 
THROUGH EARLY THURSDAY. THE EXCEPTION MIGHT BE OUR FAR NORTHEAST 
ZONES...WHERE 2 TO 3 INCH RAINFALL AMOUNTS SEEM REASONABLE.  THERE 
IS A LOW PROBABILITY OF SOME 4 INCH RAINFALL AMOUNTS IN OUR FAR 
NORTHEAST ZONES...MAINLY IN ESSEX COUNTY.  IF THIS WERE TO 
MATERIALIZE...WE MIGHT HAVE SOME FLOODING ISSUES DEPENDING ON HOW 
FAST IT FALLS.  HOWEVER...SINCE ITS A LOW PROBABILITY AND A 3RD AND 
4TH PERIOD EVENT DID NOT ISSUE ANY FLOOD HEADLINES AT THIS TIME.  
WILL NEED TO MONITOR THINGS CLOSELY...ESPECIALLY IF MODEL TRENDS 
SLIDE THE AXIS OF HEAVY RAIN A BIT FURTHER SOUTH THAN CURRENTLY 
INDICATED.  REGARDLESS...EXPECT TYPICAL NUISANCE POOR DRAINAGE 
STREET FLOODING ISSUES.

FINALLY...WE DID NOTE SOME ELEVATED INSTABILITY LATE WED INTO WED 
NIGHT.  INCLUDED A SLIGHT CHANCE OF THUNDER IN THE FORECAST...BUT DO 
NOT EXPECT ANYTHING WIDESPREAD.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...

* LONG DURATION COASTAL STORM WILL BRING RAIN THU 
* LINGERING SHOWERS POSSIBLE ON FRI
* MAINLY DRY AND SEASONABLE WEATHER THIS WEEKEND

OVERALL MODELS ARE IN FAIRLY GOOD AGREEMENT THROUGH THE LONG TERM.  
THERE ARE SOME DISCREPANCIES WITH A COUPLE OF FEATURES AS WELL AS 
SOME DIFFERENCES IN THE MESOSCALE DETAILS BUT THOSE ARE TO BE 
EXPECTED.  THE MAIN WEATHER STORY WILL BE THE LONG DURATION COASTAL 
STORM EARLY IN THE PERIOD.  AFTER THE COASTAL STORM MOVES AWAY FROM 
SOUTHERN NEW ENGLAND...THE WEATHER DRIES OUT AND BECOMES MORE 
SEASONABLE.  UPPER LEVEL FLOW FLATTENS OUT LATE IN THE WEEKEND INTO 
EARLY NEXT WEEK WITH MORE ZONAL FLOW EXPECTED.

THURSDAY...EXPECT WIDESPREAD RAIN TO CONTINUE AS A COASTAL LOW 
PRESSURE SYSTEM SLOWLY MOVES UP THE COAST TO MAINE.  AN ADDITIONAL 
HALF TO INCH AND A HALF OF RAIN IS EXPECTED ACROSS THE MAJORITY OF 
THE AREA THURSDAY.  AS THE LOW PRESSURE MOVES INTO THE GULF OF MAINE 
AND THEN THE MARITIMES...EXPECT HIGHEST AMOUNTS TO OCCUR ALONG THE 
IMMEDIATE EAST COAST OF MASSACHUSETTS...PARTICULARLY ON CAPE COD AND 
CAPE ANN WHERE RAIN WILL LAST THE LONGEST.  WITH THE HIGHER PWATS 
AND LOW LEVEL JET STRONGEST ACROSS NORTHERN NEW ENGLAND...EXPECT THE 
HEAVIEST RAIN AND THE STRONGEST WINDS TO OCCUR THERE.  THE ONE 
EXCEPTION COULD BE ALONG CAPE ANN WHERE THERE MAY BE SOME STRONG 
NORTHEASTERLY WINDS OFF THE OCEAN.  COOL...ONSHORE FLOW AND OVERCAST 
SKIES WILL KEEP TEMPERATURES IN THE 50S TO LOW 60S DURING THE DAY 
AND IN THE 50S OVERNIGHT.

FRIDAY...COULD SEE SOME LINGERING SHOWERS AS LOW PRESSURE MOVES UP 
INTO THE MARITIMES BUT WINDS SHIFT TO THE NORTHWEST BRINGING 
SOMEWHAT DRIER AIR INTO THE REGION.  OVERALL EXPECT DRIER WEATHER 
AND A GRADUAL IMPROVEMENT AS THE DAY GOES ON.

SATURDAY THROUGH MONDAY...ANOTHER UPPER LEVEL TROUGH MOVES OVER THE 
NORTHEAST BUT HERE IS WHERE WE SEE SOME DISCREPANCIES BETWEEN THE 
ECMWF AND THE GFS.  THE ECMWF HAS A STRONG NEGATIVELY TILTED UPPER 
TROUGH OVER SOUTHERN NEW ENGLAND WHILE THE GFS HAS A MORE NEUTRAL 
UPPER TROUGH.  IN BOTH MODELS LOW PRESSURE IN QUEBEC WILL PULL A 
COLD FRONT THROUGH AT LEAST A PORTION OF SOUTHERN NEW ENGLAND.  THE 
GFS IS MORE AGGRESSIVE WITH THE FRONT AND HAS MORE MOISTURE 
ASSOCIATED WITH IT...RESULTING IN A GREATER CHANCE OF SHOWERS WITH 
THE FRONT.  EXPECTING DRY SEASONABLE WEATHER SUNDAY AND MONDAY AS 
HIGH PRESSURE BUILDS ALONG THE EASTERN SEABOARD AND THEN SLIDES 
SOUTH OF SOUTHERN NEW ENGLAND.

TUESDAY...LOW PRESSURE MOVING THROUGH THE GREAT LAKES AND INTO 
QUEBEC MAY BRING A COLD FRONT THROUGH SOUTHERN NEW ENGLAND LATE 
TUESDAY AND TUESDAY NIGHT.  ANOTHER CHANCE OF SOME SHOWERS POSSIBLE 
WITH THIS FRONT BUT PLENTY OF UNCERTAINTY.

&&

.AVIATION /02Z WEDNESDAY THROUGH SUNDAY/...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /THROUGH WEDNESDAY NIGHT/...

930 PM UPDATE...

NO MAJOR CHANGES FROM 00Z TAFS. EARLIER DISCUSSION BELOW.

=================================================================

TONIGHT...MODERATE CONFIDENCE.  CONDITIONS GRADUALLY WILL LOWER TO 
MVFR FROM EAST TO WEST TONIGHT.  WE THEN EXPECT FURTHER LOWERING TO 
MAINLY IFR BY DAYBREAK WEDNESDAY...BUT TIMING REMAINS UNCERTAIN.  
AREAS OF LIGHT RAIN AND DRIZZLE WILL EXPAND OVERNIGHT IN AREAS NORTH 
OF THE MA TURNPIKE...BUT A FEW SHOWERS ARE POSSIBLE JUST ABOUT 
ANYWHERE.  PATCHY FOG MAY ALSO DEVELOP.

WEDNESDAY AND WEDNESDAY NIGHT...MODERATE TO HIGH CONFIDENCE.  LOW 
END MVFR TO IFR CONDITIONS EXPECTED.  AREAS OF LIGHT RAIN...SHOWERS 
AND DRIZZLE WILL BE COMMON FOR THE FIRST PART OF WEDNESDAY ACROSS 
THE NORTHERN ZONES AND GRADUALLY EXPAND SOUTH.  WIDESPREAD MODERATE 
TO HEAVY RAIN EXPECTED LATER WED INTO WED NIGHT.  NORTHEAST WIND 
GUSTS OF 20 TO 25 KNOTS DEVELOP ON THE COAST WED NIGHT...BUT NEAR 30 
KNOT GUSTS ARE POSSIBLE ACROSS NORTHEAST MA COAST.

KBOS...MODERATE CONFIDENCE IN TAF BUT LOW CONFIDENCE IN TRENDS.

KBDL...MODERATE CONFIDENCE IN TAF BUT LOW CONFIDENCE IN TRENDS.

OUTLOOK...THURSDAY THROUGH SUNDAY...

THURSDAY...HIGH CONFIDENCE.  MVFR/IFR CONDITIONS LIKELY IN RAIN AND 
POSSIBLY SOME ISOLATED THUNDER.  NE WINDS GUSTING UP TO 20 TO 25 KTS 
ACROSS S NH AND NE MA.

FRIDAY...HIGH CONFIDENCE.  SLOW IMPROVEMENT TO VFR EXPECTED IN 
CLEARING SKIES.

SATURDAY AND SUNDAY...MODERATE CONFIDENCE. VFR.  LOW PROBABILITY OF 
SCATTERED SHOWERS SATURDAY.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /THROUGH WEDNESDAY NIGHT/...

***HIGH SEAS AND GALE FORCE NORTHEAST WIND GUSTS POSSIBLE WEDNESDAY 
  NIGHT ACROSS OUR NORTHEAST ATLANTIC WATERS***

945 PM UPDATE...

NO MAJOR CHANGES FROM PREVIOUS FORECAST. NE WINDS WILL INCREASE
TOWARD MORNING ACROSS THE CAPE ANN WATERS WITH GUSTS OF 25-30 KT
POSSIBLE. EARLIER DISCUSSION BELOW.

======================================================================

TONIGHT...MODERATE TO HIGH CONFIDENCE.  EAST TO SOUTHEAST WINDS WILL 
SHIFT TO THE NORTHEAST LATER TONIGHT AS LOW PRESSURE LIFTS NORTHEAST 
OFF THE MID ATLANTIC COAST.  WINDS ACROSS MOST OF THE WATERS WILL 
REMAIN BELOW SCA THRESHOLDS...EXCEPT FOR THE NORTHEAST WATERS WHERE 
GUSTS TO 25 KNOTS POSSIBLE TOWARD DAYBREAK.  

WEDNESDAY AND WEDNESDAY NIGHT...MODERATE TO HIGH CONFIDENCE.  LOW 
PRESSURE WILL LIFT NORTHEAST AS AN INTENSIFYING EASTERLY LOW LEVEL 
JET DEVELOPS.  AT THE SURFACE...SHOULD SEE NORTHEAST SCA WIND GUSTS 
OVERSPREAD MOST OF OUR WATERS DURING THE DAY WEDNESDAY.  THE CORE OF 
THE STRONGEST JET WILL BE NORTH OUR WATERS WEDNESDAY NIGHT.  STILL 
THE POTENTIAL FOR A PERIOD OF NORTHEAST 35 KNOT WIND GUSTS ACROSS 
OUT FAR NORTHEAST WATERS.  THEREFORE...HAVE ISSUED A GALE WATCH FOR 
THIS LOCATION.  ALSO...SEAS MAY BUILD TO AROUND 15 FEET IN OUR 
EXTREME NORTHEAST ATLANTIC WATERS.

OUTLOOK...THURSDAY THROUGH SUNDAY...

THURSDAY...HIGH CONFIDENCE. 10 TO 15 FOOT SEAS ON THE NORTHEASTERN 
WATERS WILL SLOWLY DIMINISH THROUGH THE MORNING AND INTO THE EARLY 
AFTERNOON...5 TO 10 FOOT SEAS ELSEWHERE WILL DO THE SAME.  
NORTHEASTERLY WINDS 20 TO 25 KTS WILL SLOWLY DIMINISH THROUGH THE 
DAY AS WELL.  SMALL CRAFT ADVISORIES WILL LIKELY BE NEEDED FOR MOST 
WATERS FOR AT LEAST A PORTION OF THE DAY.

FRIDAY AND SATURDAY...HIGH CONFIDENCE. MAINLY QUIET BOATING WEATHER. 
WINDS AND SEAS INCREASE SLOWLY LATE SATURDAY NIGHT.

SUNDAY...MODERATE CONFIDENCE.  SEAS AND WINDS INCREASE GRADUALLY ON 
THE SOUTHERN WATERS...BRIEFLY REACHING SMALL CRAFT CRITERIA.

&&

.TIDES/COASTAL FLOODING...
FORTUNATELY ASTRONOMICAL HIGH TIDES ARE RATHER LOW OVER THE NEXT 48 
HOURS AND THE CORE OF THE STRONGEST WINDS WILL BE TO OUR NORTH.  
THEREFORE...THE RISK OF EVEN MINOR COASTAL FLOODING IS QUITE LOW.  
HOWEVER...THERE IS THE POTENTIAL FOR SOME MINOR BEACH EROSION ALONG 
THE SALISBURY AND PLUM ISLAND COASTS DURING THE HIGH TIDES WEDNESDAY 
NIGHT AND THURSDAY.  NO COASTAL FLOOD HEADLINES ARE ANTICIPATED 
THOUGH FOR THIS UPCOMING EVENT.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM NOON WEDNESDAY TO 8 AM EDT THURSDAY 
     FOR ANZ231>235-237.
     GALE WATCH FROM WEDNESDAY EVENING THROUGH LATE WEDNESDAY NIGHT 
     FOR ANZ250.
     SMALL CRAFT ADVISORY UNTIL 8 PM EDT WEDNESDAY FOR ANZ250.
     SMALL CRAFT ADVISORY UNTIL 8 AM EDT THURSDAY FOR ANZ251-
     254>256.

&&

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

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