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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBOX 160757
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
351 AM EDT SUN JUN 16 2013

.SYNOPSIS...
-- Changed Discussion --
A COLD FRONT WILL SLIDE OVER THE REGION OVERNIGHT THEN STALL IN
THE VICINITY OF SOUTHERN NEW ENGLAND INTO MONDAY NIGHT...LEADING TO
A PROLONGED PERIOD OF UNSETTLED WEATHER. A COLD FRONT WILL MOVE INTO
NEW ENGLAND LATE MONDAY NIGHT AND STALL DURING TUESDAY BEFORE MOVING
OFFSHORE TUESDAY NIGHT. LARGE HIGH PRESSURE WILL BRING DRY AND
SEASONABLE CONDITIONS WEDNESDAY THROUGH FRIDAY...THEN A WEAK FRONT
MAY BRING WIDELY SCATTERED SHOWERS INTO NEXT WEEKEND.
-- End Changed Discussion --

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CI AND MID LVL ALTO-CU IS GRADUALLY BUILDING OVER FROM THE W THIS
MORNING IN ADVANCE OF OCCLUDING LOW PRES. THIS LOW IS THE RESULT
OF ENERGY LEFT OVER FROM A CONVECTIVE COMPLEX WHICH WAS AFFECTING
THE OH VALLEY DURING THE OVERNIGHT HOURS...IT WILL BE THIS SYSTEM
WHICH WILL HAVE TO BE WATCHED FOR THE AFTERNOON/EVENING TIMEFRAME.

WITH CLOUDS ALREADY BEGINNING TO BUILD OVER FROM THE W...EXPECT
ONLY A PARTLY CLOUDY DAY TO GIVE WAY TO BKN-OVC CIGS BY ABOUT MID
DAY. AS THE WEAKENING SYSTEM MOVES FROM THE W...EXPECT THE BULK OF
THE ENERGY TO SHIFT TO THE N...BUT WITH THE OCCLUSION PROCESS
UNDERWAY...GUIDANCE NOW AGREES THAT SRN NEW ENGLAND WILL LIKELY BE
UNABLE TO REALIZE THE WARM SECTOR. THEREFORE...INSTABILITY WAINS
MUCH OF THE DAY WITH A FAIR AMOUNT OF CLOUD COVER. BEST
INSTABILITY/LIFT AND SHEAR IS EXPECTED TO REMAIN UPSTREAM FOR
MOST OF THE DAY. HOWEVER...WITH INCREASING MOISTURE...EXPECT THAT
AFTER 18Z...SOME -SHRA /POSSIBLY FROM WEAKENED CONVECTION/ TO MAKE
ITS WAY ACROSS IN THE W AND GRADUALLY EXPAND E AS THE FRONT WASHES
OUT. WILL INCLUDE SOME ISO THUNDER AS LAPSE RATES ARE EXPECTED TO
BEGIN TO INCREASE TOWARD THE EVENING IN ADVANCE OF A SECONDARY
COLD FRONT /MORE ON THIS BELOW/.

GIVEN ALL OF THESE FACTORS...EXPECT A AT LEAST SOME SUN TO START
GIVING WAY TO MOSTLY CLOUDY CONDITIONS WITH AT LEAST SOME SHOWERS
POSSIBLE BY LATE DAY. NOT A WASHOUT...BUT SOME AREAS WILL LIKELY
SEE DAMP GROUND BEFORE SUNSET. TEMPS WILL BE SIMILAR TO SAT
ALTHOUGH POSSIBLY A BIT COOLER GIVEN THE INCREASING CLOUDS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
TONIGHT...
THE WEAK LOW PRES WILL MOVE INTO SRN NEW ENGLAND DURING THE
OVERNIGHT HOURS...DRAGGING A WEAK SECONDARY COLD FRONT OVER THE
REGION DURING THE 00Z-06Z TIMEFRAME. THIS FRONT IS ASSOCIATED WITH
A MODEST 30 KT LLJ...AS WELL AS STEEPENING LAPSE RATES /6.5+C/KM
BY ABOUT 06Z/ THANKS TO SOME COOLING APPARENT AT ABOUT H5.
THEREFORE...STILL A THREAT FOR SOME /ELEVATED/ CONVECTION DURING
THE OVERNIGHT HOURS WHICH WILL GRADUALLY SHIFT FROM INLAND TO THE
WATERS AFTER MIDNIGHT. ONCE AGAIN...NOT A WASHOUT HERE BUT AN
OCCASIONAL HEAVY DOWNPOUR THANKS TO 1.0-1.5 INCH PWATS AND A
RUMBLE OF THUNDER IS POSSIBLE. MAY NEED TO WATCH THIS ONLY BECAUSE
OF THE RECENT RAINS WHICH HAS AFFECTED THE REGION.

WITH THE FRONT MOVING OFFSHORE EXPECT SOME IMPROVEMENT INTO THE
EARLY MORNING HOURS SAVE FOR SOME GROUND FOG AND POSSIBLE STRATUS
DEVELOPMENT ALONG THE S COAST THANKS TO RISING DWPTS AND RETURN SW
FLOW.

MONDAY...
TRICKY SITUATION REGARDING POTENTIAL THREAT FOR CONVECTIVE
ACTIVITY LATE IN THE DAY. GUIDANCE ALL SHOWS ANOTHER FAIRLY
ROBUST SHORTWAVE WRAPPING THROUGH THE CYCLONIC FLOW ALOFT DRAGGING
WITH IT YET ANOTHER FRONT ASSOCIATED WITH LOW PRES NOW IN THE
CANADIAN MARITIMES. THIS FRONT LOOKS TO PROVIDE ENOUGH OF A FOCUS
FOR LIFT DURING THE LATE AFTERNOON EVENING HOURS. THE KEY WILL BE
THE INSTABILITY. SHOULD ENOUGH SUN BREAK OUT...MODELS SB CAPE
VALUES 1000-1500 J/KG...WHICH IS HIGHER THAN PREVIOUSLY PROGGED.
THIS WOULD OF COURSE BE PREDICATED ON HOW MUCH CLOUD COVER IS LEFT
OVER FROM THE OVERNIGHT HOURS INITIALLY AS IT COULD EASILY LIMIT
THE INSTABILITY. AM NOTING 30-40 KT OF 0-6KM SHEAR HOWEVER...WHICH
SHOULD AN UPDRAFT FORM...WOULD BE ENOUGH TO SUPPORT SOME ORGANIZED
MULTICELLS WITH A WIND AND HAIL THREAT. THE BEST CHANCE LOOKS TO
BE IN THE WEST...WHERE SKIES HAVE THE BEST CHANCE OF CLEARING
DURING THE MORNING AS THE OVERNIGHT COLD FRONT SHIFTS TO THE W.
WILL NEED TO MONITOR THIS THREAT OVER THE NEXT 24 HOURS OF
FORECAST UPDATES AS NEW DATA BECOMES AVAILABLE.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...

* SHOWERS/TSTMS POSSIBLE MON NIGHT AND TUE BUT NOT A WASHOUT
* DRY AND SEASONABLE WEATHER FOR THE MIDDLE AND END OF THE WEEK

OVERVIEW AND MODEL PREFERENCES...
MODELS ARE IN PRETTY GOOD AGREEMENT ON THE OVERALL PATTERN DURING
THE EXTENDED PERIOD...BUT THERE ARE SOME DIFFERENCES IN THE DETAILS
EARLY IN THE PERIOD.  DECENT MID LEVEL TROF PASSES TO THE NORTH TUE
WITH THE ASSOCD COLD FRONT MOVING INTO NEW ENG. HOW QUICKLY THIS
FRONT MOVES OFFSHORE WITH SUBSEQUENT CLEARING IS SOMEWHAT UNCERTAIN
AS COASTAL LOW IS EXPECTED TO DEVELOP TO THE SOUTH WHICH MAY SLOW
ITS SOUTHWARD PUSH. THINK THE GFS IS TOO QUICK IN PUSHING THE FRONT
S...AND WE LEANED TOWARD ECMWF/UKMET SOLUTION WHICH IS SLOWER AND
KEEPS UNSETTLED PATTERN TUE POSSIBLY LINGERING INTO TUE NIGHT ALONG
THE COAST.  THEREAFTER...DEAMPLIFICATION OF THE PATTERN OCCURS FOR
THE LATTER HALF OF THE WEEK INTO THE WEEKEND AS THE POLAR JET LIFTS
TO THE NORTH AND RIDGE BUILDS ACROSS CENTRAL CONUS.  A PIECE OF THIS
MIDWEST HEAT WILL TRY TO SNEAK INTO SNE NEXT WEEKEND BUT WILL
PROBABLY REMAIN TO THE SW.

MON NIGHT...
WILL HAVE TO WATCH FOR ANY UPSTREAM CONVECTION SPILLING INTO SNE MON
EVENING.  INSTABILITY IS MARGINAL BUT SHEAR IS RATHER IMPRESSIVE
WHICH WILL HELP TO ORGANIZE/SUSTAIN ANY STORMS THAT MOVE INTO NEW
ENG.  NOT CERTAIN THERE WILL BE STORMS BUT ANY THAT DEVELOP WILL
HAVE TO BE MONITORED GIVEN MAGNITUDE OF DEEP LAYER SHEAR.
OTHERWISE...THREAT OF SHOWERS AND ISOLATED TSTMS WILL CONTINUE
THROUGH THE NIGHT AS THE COLD FRONT MOVES INTO THE REGION FROM THE
WEST.

TUESDAY INTO TUE NIGHT...
AS MENTIONED ABOVE WE LEANED TOWARD SLOWER ECMWF SOLUTION WITH FRONT
LIKELY STALLING ACROSS NEW ENG TUE.  EXPECT LOTS OF CLOUDS TUE WITH
CONTINUED CHC OF SHOWERS/TSTMS WHICH MAY LINGER NEAR THE S COAST TUE
EVENING AS THE FRONT TAKES ITS TIME MOVING OFFSHORE. EVENTUALLY
CLEARING WILL MOVE IN FROM NORTH TO SOUTH LATER TUE NIGHT.

WEDNESDAY THROUGH FRIDAY...
LARGE HIGH PRES BUILDS INTO THE REGION WHICH WILL BRING DRY AND
SEASONABLE TEMPS. MODERATION EXPECTED BY THE END OF THE WEEK AS THE
HIGH MOVES TO THE S WITH RETURN FLOW DEVELOPING.

SATURDAY...
MORE CLOUDS AND POSSIBLY A FEW SHOWERS AS WARM FRONT APPROACHES FROM
THE SW...BUT THIS IS UNCERTAIN AT DAY 7.

&&

.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

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

OVERVIEW...HIGH CONFIDENCE THROUGH MONDAY.

TODAY INTO TONIGHT...
VFR EXPECTED TO DOMINATE INTO THE EARLY OVERNIGHT HOURS.
HOWEVER...OCCASIONAL BRIEF MVFR CONDITIONS ARE POSSIBLE FROM W TO
E IN -SHRA BEGINNING AFTER 18Z AND CONTINUING THROUGH ABOUT 04Z.
SOME THUNDER ALSO POSSIBLE...BUT NOT EXPECTED TO BE WIDESPREAD.
SOME FOG POSSIBLE LATE TONIGHT...ESPECIALLY AIRPORTS THAT RECEIVE
DRAIN.

MONDAY...
MAINLY VFR THROUGH THE DAY. ANOTHER CHANCE FOR AFTERNOON
THUNDERSHOWERS ESPECIALLY AT INTERIOR SRN NEW ENGLAND TERMINALS.

KBOS TERMINAL...HIGH CONFIDENCE IN OVERALL TAF TRENDS...SLIGHTLY
LOWER CONFIDENCE IN TIMING OF -SHRA THIS LATE IN THE DAY.

KBDL TERMINAL...HIGH CONFIDENCE IN OVERALL TAF TRENDS...SLIGHTLY
LOWER CONFIDENCE IN TIMING OF -SHRA THIS LATE IN THE DAY.

OUTLOOK...MONDAY NIGHT THROUGH THURSDAY...

MONDAY NIGHT THROUGH TUESDAY NIGHT...MODERATE CONFIDENCE. AREAS OF
MVFR/IFR STRATUS AND FOG MON NIGHT...ESPECIALLY NEAR THE COAST.
OTHERWISE MVFR POSSIBLE AT TIMES IN SCT SHOWERS AND TSTMS.

WEDNESDAY AND THURSDAY...HIGH CONFIDENCE. VFR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

THROUGH MONDAY...MODERATE CONFIDENCE.

WIND GUSTS APPROACHING 25 KT ARE POSSIBLE ALONG THE NEAR SHORT
WATERS SURROUNDING CAPE COD...THE ISLANDS AND NARRAGANSETT BAY
THIS AFTERNOON...SO HAVE OPTED TO HOIST A BRIEF AFTERNOON SMALL
CRAFT ADVISORY GIVEN AN OTHERWISE GOOD BOATING DAY.

OVERNIGHT...A COLD FRONT COULD BRING THE THREAT FOR SHOWERS AND
THUNDERSTORMS...WHICH MAY PRODUCE LOCALIZED VSBY AND WIND ISSUES.
WITH PERSISTENT SOUTH FLOW TODAY...SEAS MAY APPROACH 5-6 FT ON
SOUTHERN OCEAN WATERS SO HAVE AN OVERNIGHT SMALL CRAFT ADVISORY
FOR THIS THREAT AS WELL.

FINALLY...ON MONDAY...MAINLY QUIET BOATING WEATHER IS
EXPECTED...HOWEVER SOME THUNDERSTORMS COULD FORM OVER LAND AND
GRADUALLY MAKE THEIR WAY OVER THE WATERS LATE IN THE DAY.

OUTLOOK...MONDAY NIGHT THROUGH THURSDAY...

MODERATE CONFIDENCE THROUGH THE PERIOD.

WINDS AND SEAS MOSTLY BELOW SCA THRESHOLDS...ALTHOUGH N/NE WIND
GUSTS COULD APPROACH 25 KT LATE TUE NIGHT AND WED.

&&

.HYDROLOGY...
RIVERS ACROSS SOUTHERN NEW ENGLAND HAVE CRESTED AND ARE GRADUALLY
RECEDING THANKS TO A DAY+ OF DRY WEATHER. FOR MORE DETAILED
INFORMATION REGARDING ANY FLOOD WARNINGS CURRENTLY IN EFFECT SEE
THE LATEST FLOOD STATEMENT. THE LIST BELOW IS A GENERAL LIST OF
THOSE RIVERS THAT STILL REMAIN ABOVE MINOR FLOOD.

WILL NEED TO MONITOR THE LATE DAY/EVENING HOURS TODAY AND
LATE DAY MONDAY TIMEFRAMES FOR SOME SHOWERS AND ISOLATED
THUNDERSTORMS WHICH COULD PRODUCE HEAVY DOWNPOURS. NOT EXPECTING
NEARLY AS WIDESPREAD HEAVY RAINFALL AS FELL LAST WEEK...BUT SOME
ISOLATED AREAS COULD SEE SOME LOCALIZED HEAVY RAIN WHICH MAY NEED
TO BE MONITORED FOR FURTHER URBAN FLOODING.

RIVER FORECAST POINTS WHERE FLOOD WARNINGS ARE STILL IN EFFECT AS
OF 430 AM...

IN CT...
FARMINGTON RIVER AT SIMSBURY
CONNECTICUT RIVER AT HARTFORD
CONNECTICUT RIVER AT MIDDLE HADDAM

IN MA...
ASSABET RIVER AT MAYNARD - EXPECTED TO REACH FLOOD STAGE MID MORN
CHARLES RIVER AT DOVER

IN RI...
PAWTUXET RIVER AT CRANSTON

IN ADDITION...AN AREAL FLOOD WARNING IS IN EFFECT FOR SOUTHWESTERN
WASHINGTON COUNTY IN RI WHERE THE LOWER PAWCATUCK RIVER REMAINS IN
FLOOD.

REFER TO THE LATEST FLOOD STATEMENTS FOR SPECIFIC FORECASTS.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 8 PM EDT THIS
     EVENING FOR ANZ231>234-236.
     SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 8 AM EDT MONDAY
     FOR ANZ255-256.

&&

$$
SYNOPSIS...KJC/DOODY
NEAR TERM...DOODY
SHORT TERM...DOODY
LONG TERM...KJC
AVIATION...KJC/DOODY
MARINE...KJC/DOODY
HYDROLOGY...STAFF