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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBOX 152359
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
759 PM EDT SAT JUN 15 2013

.SYNOPSIS...
HIGH PRESSURE BUILDS OVER THE REGION THRU SUNDAY WITH MOSTLY DRY
AND SEASONABLE CONDITIONS. LOW PRESSURE SLOWLY MOVE ACROSS NEW
ENGLAND...BRINGING THE CHANCE FOR SHOWERS AND ISOLATED
THUNDERSTORMS FROM LATE SUNDAY THROUGH TUESDAY. LARGE HIGH
PRESSURE WILL BRING DRY AND SEASONABLE CONDITIONS INTO LATE NEXT
WEEK...THEN A WEAK FRONT MAY BRING WIDELY SCATTERED SHOWERS INTO
NEXT WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
-- Changed Discussion --
745 PM UPDATE...
THE FEW CLOUDS THAT DEVELOPED ACROSS THE INTERIOR HAVE STARTED TO
DISSIPATE AS THE SUN SETS THIS EVENING. AFTERNOON HIGHS TOUCHED
AROUND 80 ACROSS MANY LOCATIONS EXCEPT ALONG THE IMMEDIATE S
COAST...THEN A FEEBLE SEA BREEZE KICKED IN AT KGHG AND EVEN KPYM
AS WINDS DIMINISHED LATE THIS AFTERNOON.

EXPECT CLOUDS TO CONTINUE TO DISSIPATE...SO SHOULD SEE MAINLY
CLEAR SKIES EARLY TONIGHT. NOTING SOME MID AND HIGH CLOUDS WORKING
SE OUT OF S ONTARIO INTO WESTERN NY STATE WHICH MAY TRY TO SNEAK
IN LATER THIS EVENING ON THE STRONG NW WINDS ALOFT.

PREVIOUS DISCUSSION...
TONIGHT...UPPER LEVEL RIDGE CRESTS OVER THE AREA WHILE HIGH
PRESSURE BUILDS AT THE SURFACE. EXPECT CONTINUED CLEAR SKIES AND
CALM WINDS OVERNIGHT. THIS WILL LEAD TO GOOD RADIATIONAL COOLING
WITH LOWS IN THE UPPER 40S TO LOW 50S AWAY FROM THE COAST. LOW
TEMPERATURES IN THE URBAN CENTERS AND ALONG THE COAST WILL BE IN
THE MID TO UPPER 50S.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
SUNDAY...LOW PRESSURE MOVES FROM THE GREAT LAKES INTO WESTERN
QUEBEC. THE NAM/GFS INDICATE A SECONDARY SURFACE LOW PRESSURE
DEVELOPING NEAR OR OVER SOUTHERN NEW ENGLAND. THIS IN COMBINATION
WITH A SHORTWAVE MOVING OVER THE REGION WILL BE ENOUGH TO INDUCE
SHOWERS ACROSS THE AREA. USED A BLEND OF GUIDANCE FOR THE ONSET OF
SHOWERS THAT KEEPS THE MORNING DRY AND STARTS SHOWERS IN THE WEST
DURING THE AFTERNOON AS THE HIGH PRESSURE MOVES OFFSHORE.
INSTABILITY IS LIMITED AS EXHIBITED IN THE MID LEVEL LAPSE RATES
AND THE INSTABILITY PARAMETERS...SO HAVE KEPT JUST AN ISOLATED
MENTION OF THUNDER IN FOR THE AFTERNOON. TEMPERATURES SHOULD BE
SIMILAR TO TODAY OR A FEW DEGREES COOLER...DEPENDENT ON THE EXTENT
OF THE CLOUD COVER.

SUNDAY NIGHT...THE SECONDARY LOW PRESSURE SYSTEM WILL MOVE
OFFSHORE TOWARDS THE MARITIMES WHILE THE PRIMARY LOW MOVES
EASTWARD SLOWLY ACROSS QUEBEC. SHOWERS AND ISOLATED THUNDERSTORMS
REMAIN POSSIBLE ACROSS MUCH OF THE AREA AHEAD OF A COLD FRONT AS
LAPSE RATES STEEPEN.

&&

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

* SHOWERS POSSIBLE AT TIMES THROUGH TUE BUT NOT A WASHOUT
* DRY AND SEASONABLE WEATHER FOR THE MIDDLE AND END OF THE WEEK

OVERVIEW AND MODEL PREFERENCES...

MEDIUM RANGE MODELS CONTINUE TO SHOW BROAD H5 TROUGHING ON BOTH
COASTS WITH RIDGING ACROSS THE CENTRAL U.S. AT THE START OF THIS
TIMEFRAME. THIS PATTERN STARTS TO RELAX...WITH MORE BROAD ZONAL
UPPER LEVEL FLOW ACROSS THE NORTHERN TIER STATES KEEPING WEAK
WEATHER SYSTEMS MOVING ALONG WITHOUT THE OPPORTUNITY TO TAP THE
ATLANTIC OR GULF. SO...EXPECT WEAK DISTURBANCES TO MOVE ALONG IN
THE UPPER FLOW. THE ONLY EXCEPTION WILL BE EARLY NEXT WEEK AS LOW
PRESSURE MAY FORM ALONG DEPARTING COLD FRONT...SLOWING ITS
PROGRESS OFFSHORE THROUGH TUESDAY NIGHT. GFS CONTINUES TO DEVELOP
THIS SYSTEM MORE ROBUSTLY THAN THE GGEM AND ECMWF...BUT THE EC AND
GFS BOTH HAVE THIS FURTHER OFFSHORE. BEYOND THIS...MODELS ARE IN
GOOD AGREEMENT IN BRINGING HIGH PRES OUT OF THE GREAT LAKES IN THE
DEVELOPING BROAD ZONAL FLOW...BRINGING DRY CONDITIONS WED-THU.
LATE NEXT WEEK...SOME DIVERGENCE IN MODEL SOLUTIONS AS THE HIGH
BUILDS OFFSHORE AND POSSIBLE DIURNAL SHOWER DEVELOPMENT IN THE
SW SURFACE FLOW. FOR NOW...KEPT IT DRY BUT DID BRING IN SLIGHT
CHANCE POPS DURING EACH AFTERNOON/EVENING LATE IN THIS PERIOD.

LEANED TOWARD A BLEND OF THE PREVIOUS FORECAST ALONG WITH THE WPC
GUIDANCE AND EC/ECENS...THOUGH MOST MODELS WERE IN FAIR TO GOOD
AGREEMENT.

DETAILS...

MONDAY...
SHOULD SEE MAINLY DRY CONDITIONS EARLY IN THE DAY...THEN ANOTHER
SHOT OF SCT SHOWERS/ISOLD TSTMS WILL PUSH IN FROM THE NW AS COLD
FRONT APPROACHES. NOT MUCH MOISTURE WITH THIS FEATURE...HOWEVER.
KEPT ONLY LOW CHANCE POPS GOING INTO MON EVENING. WILL BE A WARM
DAY ON THE SW FLOW WITH HIGHS AROUND 80...MILDEST IN THE LOWER CT
VALLEY...BUT HOLDING IN THE 70S ALONG THE S COAST WITH THE COOL
ONSHORE FLOW.

MONDAY NIGHT AND TUESDAY...
WHILE THE COLD FRONT SLOWLY MOVES ACROSS THE REGION WITH A LITTLE
DIGGING OF ITS ASSOCIATED UPPER TROUGH...MAY STILL SEE ISOLD TSTM
ACTIVITY EARLY. ALSO NOTING WAVE DEVELOPING ON THIS FRONT AS
MENTIONED ABOVE. HAVE CONTINUED CHANCE POPS...THOUGH MAY BE A
LITTLE MORE ENHANCED ACROSS SOUTHERN AREAS LATE MON NIGHT AND
TUE...THEN THE FRONT SHOULD CLEAR THE S COAST. HIGHS FALL BACK A
FEW DEGS ON TUESDAY.

TUESDAY NIGHT THROUGH THURSDAY...
LEFTOVER SHOWERS ACROSS SOUTHERN AREAS WILL EXIT TUE NIGHT.
THEN...AS UPPER LEVEL PATTERN FLATTENS OUT...LARGE HIGH PRES WILL
BUILD OUT OF THE GREAT LAKES TOWARD THE MID ATLC COAST. THE
POSITION OF THE HIGH ON WED ALONG WITH ANOTHER WAVE ON THE
DEPARTING FRONT WILL CAUSE A PRETTY GOOD NE FLOW TO KICK IN. MAY
SEE SOME GUSTS UP TO AROUND 20 MPH FROM AROUND PLYMOUTH SOUTH TO
THE CAPE AND ISLANDS. WEDNESDAY WILL BE A DRY BUT COOL DAY WITH
HIGHS ONLY IN THE 70S...RUNNING A GOOD 5 DEGS BELOW SEASONAL
NORMS.

ON THURSDAY...THE HIGH WILL MOVE ACROSS SW NEW ENGLAND THEN
POSITION OFF THE MID ATLC COAST...SO SHOULD SEE TEMPS REBOUND TO
MORE SEASONABLE LEVELS.

FRIDAY-SATURDAY...HIGH PRES OFF THE MID ATLC COAST WILL START TO
PUMP MILDER AIR UP THE COAST ALONG WITH INCREASING HUMIDITIES.
WEAKENING COLD FRONT WILL TRY TO WORK INTO THE REGION...SO MAY SEE
WIDELY SCT SHOWERS DEVELOP DURING THE AFTERNOON AND EVENING HOURS
EACH DAY WITH THE DIURNAL HEATING. NOT REAL GOOD LIFT IN PLACE SO
DID NOT MENTION THUNDER FOR NOW.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --
FORECASTER CONFIDENCE LEVELS...

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

OVERVIEW...HIGH CONFIDENCE THROUGH SUNDAY NIGHT.

TONIGHT...VFR. LOW PROBABILITY OF SOME GROUND FOG AT TYPICALLY
PRONE AIRPORTS.

SUNDAY...MAINLY VFR. LOW CONFIDENCE IN BRIEF MVFR CONDITIONS IN
SCT -SHRA DURING THE AFTN.

SUNDAY NIGHT...AREAS OF MVFR/IFR IN LOW CLOUDS...FOG...AND SCT
-SHRA.  OTHERWISE...VFR.

KBOS TERMINAL...HIGH CONFIDENCE IN TAF.

KBDL TERMINAL...HIGH CONFIDENCE IN TAF.

OUTLOOK...MONDAY THROUGH THURSDAY...

MONDAY THROUGH TUESDAY NIGHT...MODERATE CONFIDENCE. MAINLY
VFR...BUT BRIEF MVFR POSSIBLE IN SCT SHOWERS. LOW PROB FOR
ISOLD TSTMS.

WEDNESDAY-THURSDAY...HIGH CONFIDENCE. VFR.
-- End Changed Discussion --

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

THROUGH SUNDAY NIGHT...HIGH CONFIDENCE.

QUIET BOATING WEATHER EXPECTED THIS AFTERNOON AND TONIGHT WITH
SEAS BELOW 5 FEET AND WNW WINDS 10-15 KT SHIFTING TO THE SOUTHWEST
TONIGHT. USED THE SLOWER SWANNAM WAVE HEIGHTS...WHICH BRINGS SEAS
UP TO ABOUT 5 FEET ON THE SOUTHERN WATERS SUNDAY NIGHT. SW WINDS
WILL INCREASE SUNDAY TO 15-20 KT BUT EXPECT THEY WILL REMAIN
BELOW 25 KT AT THIS POINT. SHOWERS AND AN ISOLATED THUNDERSTORM
MAY REDUCE VISIBILITIES AT TIMES LATE SUNDAY AND SUNDAY NIGHT.

OUTLOOK...MONDAY THROUGH THURSDAY...

MODERATE CONFIDENCE THROUGH THE PERIOD.

MONDAY-TUESDAY...WINDS WILL REMAIN BELOW SMALL CRAFT CRITERIA.
SEAS MAY LINGER AROUND 5 FT ON THE OUTER WATERS THROUGH
TUESDAY...THEN SHOULD SUBSIDE TUE NIGHT.

WEDNESDAY-THURSDAY...WINDS SHIFT TO NE...GUSTING UP TO 20 KT
MAINLY ON WED. SEAS WILL RUN UP TO 5-6 FT ON THE OUTER WATERS
WED AND WED NIGHT...THEN SHOULD SUBSIDE DURING THU.

&&

.HYDROLOGY...
-- Changed Discussion --
MANY RIVERS REMAIN ABOVE FLOOD STAGE ACROSS THE AREA...SEE BELOW
FOR A LISTING OF THESE. ALL OF THE AREA RIVERS HAVE CRESTED AND
CONTINUE TO SLOWLY RECEDING.

RIVER LEVELS AT A FEW SITES ARE FORECAST TO FALL BELOW FLOOD
STAGE DURING SUNDAY...WHILE OTHERS WILL LIKELY TAKE LONGER. SEE
THE LATEST FLOOD STATEMENT FOR MORE SPECIFIC INFORMATION.

DRY WEATHER IS EXPECTED THROUGH EARLY SUNDAY. THE NEXT THREAT FOR
PRECIPITATION WILL BE LATE DAY SUN INTO SUN NIGHT. THIS RAIN WILL
NOT BE AS WIDESPREAD OR HEAVY AS PREVIOUS RAIN EVENTS WERE...AND
WILL LIKELY BE MORE SHOWERY IN NATURE. AN ISOLATED THUNDERSTORM
COULD PRODUCE SLIGHTLY HEAVIER RAINFALL DURING THE EVENING AND
OVERNIGHT HOURS...BUT THIS WOULD BE VERY LOCALIZED. WIDESPREAD
PRECIP AMOUNTS ARE EXPECTED TO BE A QUARTER INCH OR LESS THROUGH
MONDAY MORNING.

RIVER FORECAST POINTS WHERE FLOOD WARNINGS ARE STILL IN EFFECT AS
OF 730 PM...

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

IN MA...
ASSABET RIVER AT MAYNARD
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.
-- End Changed Discussion --

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...RLG/EVT
NEAR TERM...RLG/EVT
SHORT TERM...RLG
LONG TERM...EVT
AVIATION...RLG/EVT
MARINE...RLG/EVT
HYDROLOGY...RLG/EVT