Area Forecast Discussion
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000
FXUS61 KBOX 130810
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
410 AM EDT SUN JUL 13 2014

.SYNOPSIS...
DRY/PLEASANT WEATHER LINGERS ACROSS MUCH OF SOUTHERN NEW ENGLAND
TODAY...ALTHOUGH BREEZY CONDITIONS DEVELOP. SHOWERS AND ISOLATED
THUNDERSTORMS WILL ENTER WESTERN NEW ENGLAND LATE TODAY AND THEN
INTO EASTERN MA AND RI TONIGHT. A FRONTAL BOUNDARY WILL STALL ACROSS
THE REGION MONDAY THROUGH WEDNESDAY YIELDING NUMEROUS SHOWERS AND
THUNDERSTORMS. A FEW STORMS MAY BE STRONG ESPECIALLY MONDAY WITH THE
THREAT OF FLASH FLOODING INTO WED. A TREND TOWARD DRIER AND SOMEWHAT
LESS HUMID WEATHER FOLLOWS LATE IN THE WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

400AM UPDATE....

UPPER LEVEL CLOUD DEBRIS FROM GREAT LAKES CONVECTION CONTINUES TO
SPILL INTO SOUTHERN NEW ENGLAND EARLY THIS MORNING. SOUTHERLY FLOW
OVERNIGHT HAS ALLOWED FOR AN INCREASE IN SURFACE MOISTURE SO SOME
PATCHY GROUND FOG MAY DEVELOP OVER THE NEXT FEW HOURS. ASIDE FROM
SOME MINOR TWEAKS...FORECAST REMAINS ON TRACK FOR THE EARLY
MORNING HOURS.

TODAY...

UPPER LEVEL TROUGH WILL BEGIN TO SWING ITS WAY TOWARDS THE GREAT
LAKES REGION TODAY. A WEAK WAVE AT 700MB WILL MOVE THROUGH THE FLOW
SPARKING OFF SOME SHOWERS AND THUNDERSTORMS...ESPECIALLY ACROSS THE
MIDWEST AND INTO UPSTATE NEW YORK AS THE BEST FORCING/LIFT IS WELL
TO OUR WEST. THEREFORE BELIEVE THAT MUCH OF THE REGION SHOULD REMAIN
DRY TODAY. HOWEVER FOR LOCATIONS WEST OF THE CENTRAL HILLS...BELIEVE
A FEW ISOLD SHOWERS MAY TRICKLE IN BY THE LATE AFTERNOON/EARLY
EVENING HOURS. PWATS ARE INCREASING CLOSE TO 2 INCHES AND WITH
850MB LLJ INCREASING...COULD SEE SOME HEAVY RAINFALL OUT OF ANY
THUNDERSTORM THAT DEVELOP. CAPE VALUES ARE INCREASING TO 1000 J/KG
AND 0-6 KM SHEAR VALUES AROUND 25-30 KTS MAY ALLOW FOR SOME GUSTY
WINDS. AGAIN BELIEVE AREAL COVERAGE WILL BE ISOLATED BY THE LATE
AFTERNOON...BUT INCREASE INTO THE EVENING/OVERNIGHT HOURS AS
ANOTHER SHORTWAVE APPROACHES SOUTHERN NEW ENGLAND.

SOUNDINGS SUGGEST THAT THE ATMOSPHERE WILL MIX UP TO 850 MB
ALLOWING FOR TEMPS TO WARM UP TO THE MID 80S. THIS MIXING WILL
ALSO ALLOW SURFACE WINDS TO INCREASE AND GUST BETWEEN 20-30 MPH
TODAY. DEWPOINTS WILL ALSO BE ON THE INCREASE WHICH WILL ALLOW FOR
THE RETURN OF THAT SUMMERTIME MUGGINESS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...

TONIGHT...

UPPER LEVEL TROUGH WILL CONTINUE TO DOMINATE OVER THE GREAT LAKES
REGION TONIGHT. THIS WILL ALLOW FOR AN INCREASE IN LOW LEVEL
MOISTURE AS WELL AS WITH BETTER JET DYNAMICS...THE THREAT FOR
SCATTERED SHOWERS/THUNDERSTORMS WILL INCREASE AS THE NIGHT WEARS
ON. GIVEN PWATS ON THE ORDER OF 2+ INCHES...LOCALLY HEAVY RAINFALL
WILL ALSO BE AN INCREASING CONCERN.

IT WILL BE MUGGY WITH LOW TEMPS ONLY BOTTOMING OUT IN THE UPPER 60S
TO LOWER 70S.

TOMORROW...

FIRST WAVE OF HEAVY RAINFALL SHOULD EXIT THE REGION EARLY MONDAY
MORNING BEFORE ANOTHER ROUND APPROACHES BY THE LATE AFTERNOON. THERE
COULD BE A BREAK IN PRECIP DURING THE DAY AND IN FACT CROSS SECTIONS
ARE SHOWING A BRIEF BREAK IN MOISTURE/RH AT THE MID-LEVELS WHICH MAY
ALLOW FOR BREAKS IN THE CLOUD COVER. THIS WILL HELP INCREASE DIURNAL
HEATING AND SUCH THE POTENTIAL FOR STRONG/SEVERE THUNDERSTORMS.

ASIDE...ANOMALOUS LOW WILL SET UP OVER THE GREAT LAKES PUSHING THE
TROUGH AXIS OVER THE MIDWEST KEEPING SNE IN THE SOUTHWEST FLOW. THIS
WILL CONTINUE TO INCREASE THE MOISTURE PROFILES AS DEWPOINTS REACH
ABOVE 70F. ANOTHER SHORTWAVE WILL RIDE THROUGH THE FLOW ON MONDAY
SPARKING OFF ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS. BELIEVE
AREAL COVERAGE WILL BE MORE THEN SUNDAY...ALTHOUGH A FEW OF THE HI-
RES GUIDANCE SHOWS MORE OF AN ISOLATED COVERAGE. HOWEVER MANY OF THE
SYNOPTIC MODELS SHOW QPF AND WITH THE AMOUNT OF LIFT AND MOISTURE IN
THE PROFILE BELIEVE COVERAGE WILL BE MORE SCT/WIDESPREAD. CAPE
VALUES WILL INCREASE BETWEEN 1500-2000 J/KG AND WITH 0-6 KM BULK
SHEAR VALUES REACHING 45 KTS...COULD SEE STRONG AND PERHAPS SEVERE
WEATHER WITH DAMAGING WINDS AND HEAVY RAINFALL BEING THE MAIN
THREATS. AS DEWPOINTS WILL REACH INTO THE 70S...CANNOT RULE OUT THE
POTENTIAL FOR A QUICK SPIN-UP IN THIS SOMEWHAT TROPICAL AIRMASS AS
WELL AS 0-1 KM SHEAR VALUES NEAR 20-25KTS. KEEP AN EYE TO THE SKY
AND STAY TUNED FOR UPDATES TO THE FORECAST AS THE SEVERE WEATHER
POTENTIAL CAN CHANGE.

&&

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

* NUMEROUS SHOWERS & THUNDERSTORMS MON NGT INTO WED WITH HEAVY RAIN
  AND ISOLATED FLASH FLOOD POTENTIAL
* WARM AND VERY HUMID MON NIGHT AND TUESDAY
* IMPROVING WEATHER WITH DRIER AND LESS HUMID CONDITIONS THU AND FRI

ENSEMBLES AND DETERMINISTIC GUIDANCE CONTINUE TO SUPPORT A HIGH
AMPLITUDE PATTERN ACROSS NORTH AMERICA WITH AN ANOMALOUS TROUGH OF
-3 SD /500 MB HEIGHTS/ DIVING INTO THE GREAT LAKES MON. THIS TROUGH
WILL BE SLOW MOVING AS DOWNSTREAM RIDGING DEVELOPS OVER THE
NORTHWEST ATLC. THE SLOW MOVEMENT OF THIS TROUGH WILL RESULT IN A
STALLED FRONTAL BOUNDARY ACROSS NEW ENGLAND FROM SUN NIGHT INTO
WED. THE HIGH AMPLITUDE PATTERN ALSO RESULTS IN MERIDIONAL FLOW ALONG
THE EASTERN SEABOARD WITH PWATS UP TO +2 SD STREAMING POLEWARD INTO
NEW ENGLAND FROM SUN NIGHT INTO WED. THIS DURATION COUPLED WITH DEEP
UNIDIRECTIONAL FLOW WILL PROVIDE AN ENVIRONMENT FAVORABLE FOR BACK
BUILDING AND TRAINING CELLS. THUS A RISK FOR ISOLATED FLASH
FLOODING. BOTH 00Z EC AND GFS CONTINUE TO OFFER HEAVY QPF WITH 1-3"
ACROSS THE REGION FROM TONIGHT THRU WED. 00Z GEFS ENSEMBLES NOT AS
BULLISH WITH VERY LOW PROBS OF 2+ INCHES.

IN ADDITION...THIS HIGH AMPLITUDE PATTERN YIELDS AN ANOMALOUS /+2
SD/ UPPER LEVEL JET STREAK ACROSS THE NORTHEAST AND SOUTHEAST
CANADA. THESE STRONG WIND FIELDS COUPLED WITH MODEST INSTABILITY
WILL PROVIDE A LOW RISK OF A FEW STRONG TSTMS.

AS FOR GUIDANCE ASSESSMENT...THE 00Z GFS AND GEFS HAS FINALLY COME
AROUND TO THE SLOWER SOLUTIONS OF THE ECMWF AND ECENS. THE HIGHER
RES OPERATIONAL RUNS OF THE ECMWF AND GFS ARE IN GOOD AGREEMENT THAT
A WAVE WILL TRACK UP THE FRONT TUE NIGHT INTO WED. THIS WILL SLOW
THE FRONT/S DEPARTURE AND LIKELY KEEP SHOWERS/TSTMS IN THE FORECAST
AT LEAST THRU EARLY WED. THIS FRONTAL WAVE WILL ALSO ENHANCE THE
RISK FOR HEAVY RAIN AND ASSOCIATED FLASH FLOODING. MODELS THEN MOVE
THE FRONT OFFSHORE LATE WED/WED NIGHT ALONG WITH MID/UPPER LEVEL
TROUGH DEAMPLIFYING. THIS SUPPORTS A TREND TOWARD DRIER AND LESS
HUMID WEATHER THU AND FRI.

&&

.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /THROUGH MONDAY/...

BEFORE 12Z...VFR. PATCHY DENSE FOG IN NORMAL PRONE REGIONS.

TODAY...HIGH CONFIDENCE IN MAINLY VFR CONDITIONS. GUSTY SOUTHERLY
WINDS BETWEEN 20-30 KTS. A FEW SHOWERS/THUNDERSTORMS MAY IMPACT
WESTERN SITES LATE THIS AFTERNOON...RESULTING IN LOCALIZED LOWER
CONDITIONS.  HOWEVER...THIS ACTIVITY WILL LIKELY REMAIN WEST OF ALL
OUR FORECAST TERMINALS FOR MOST OF THE DAY.

TONIGHT...MODERATE CONFIDENCE.  MVFR-IFR CIGS/VSBYS OVER SPREAD THE
REGION AS DEEP LOW LEVEL MOISTURE WORKS INTO THE REGION.  THE RISK
FOR SCATTERED SHOWERS/THUNDERSTORMS INCREASES THROUGH THE
OVERNIGHT HOURS.

TOMORROW...MODERATE CONFIDENCE. VFR/MVFR CONDITIONS THROUGHOUT THE
DAY DROPPING TO MVFR/IFR IN SCATTERED SHOWERS/THUNDERSTORMS. A
FEW OF THESE THUNDERSTORMS MAY PRODUCE VERY STRONG WINDS.

KBOS TAF...HIGH CONFIDENCE IN TAF.

KBDL TAF...HIGH CONFIDENCE IN TAF. LOW PROB OF ISOLATED
SHOWER/THUNDERSTORM AFTER 21Z.

OUTLOOK...MONDAY NIGHT THROUGH THURSDAY...

MONDAY NIGHT AND TUESDAY...NUMEROUS SHOWERS AND SCATTERED TSTMS WITH
HEAVY DOWNPOURS LIKELY. PATCHY FOG AT NIGHT LIKELY YIELDING MVFR/IFR
CONDITIONS...THEN LIFTING TO MARGINAL VFR DURING THE LATE MORNING
AND AFTERNOON. MODERATE TO HIGH CONFIDENCE.

WEDNESDAY...IFR/MVFR EASTERN MA AND RI WITH VFR/MVFR WESTERN CT/MA.
GREATEST RISK OF SHOWER/TSTMS AND PATCHY FOG ACROSS RI AND EASTERN
MA. MODERATE CONFIDENCE.

THURSDAY...TREND TOWARD VFR ALONG WITH DRY WEATHER. MODERATE
CONFIDENCE.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...HIGH CONFIDENCE.

TODAY AND TONIGHT...INCREASING SOUTHWEST FLOW AND GOOD MIXING OVER
THE LAND SHOULD ALLOW SOUTHWEST WIND GUSTS OF 25 TO 30 KNOTS TO
DEVELOP LATE THIS MORNING AND PARTICULARLY DURING THE AFTERNOON
HOURS ACROSS THE NEAR SHORE WATERS. LONG SOUTHWEST FETCH SHOULD
ALLOW SCA SEAS TO DEVELOP ON THE OUTER-WATERS TONIGHT.
THEREFORE...SCA HEADLINES POSTED FOR ALL WATERS FOR THE ABOVE
CONCERNS.  IN ADDITION...SOME FOG MAY DEVELOP SUNDAY NIGHT AND WE
CAN/T RULE OUT A FEW THUNDERSTORMS PARTICULARLY TOWARD DAYBREAK
MONDAY.

MONDAY...SCA HAS BEEN EXTENDED FOR THE OUTER WATERS AS SEAS WILL
STILL BE ABOVE 5 FT. MAIN CONCERN IS THE POTENTIAL FOR THUNDERSTORMS
BY THE AFTERNOON/EVENING HOURS. SOME OF THESE STORMS COULD BE
STRONG/SEVERE.

OUTLOOK...MONDAY NIGHT THROUGH THURSDAY...

MONDAY NIGHT-TUESDAY...COLD FRONT REMAINS WEST OF NEW ENGLAND
WATERS. THUS SSW WINDS 15-20 KT CONTINUES WITH GUSTS UP TO 25 KT
POSSIBLE. SCATTERED TSTMS WITH TORRENTIAL DOWNPOURS. LOW RISK OF A
TSTM WITH STRONG WINDS. VSBY REDUCED AT TIMES IN PATCHY FOG.
MODERATE TO HIGH FORECAST CONFIDENCE.

WEDNESDAY...TRANSITION DAY WITH FRONT SLOWLY MOVING ACROSS NEW
ENGLAND AND THE COASTAL WATERS. HEAVY SHOWERS AND SCATTERED TSTMS
CONTINUE ALONG WITH PATCHY MORNING FOG. HOWEVER COULD SEE SOME
IMPROVEMENT LATE IN THE DAY AND ESPECIALLY AT NIGHT AS FRONT
CONTINUES TO MOVE EAST. SSW WINDS 15-20 KT WILL SLACKEN AND BECOME
WSW LATE OR AT NIGHT. MODERATE CONFIDENCE.

THURSDAY...BIG IMPROVEMENT WITH DRIER WEATHER AND IMPROVING VSBY.
FAIRLY LIGHT WINDS EXPECTED.

&&

.TIDES/COASTAL FLOODING...
VERY HIGH ASTRONOMICAL HIGH TIDES WITH BOSTON AT 12.2 FEET AROUND
MIDNIGHT TONIGHT. HOWEVER...SOUTH TO SOUTHWEST WINDS WILL PREVENT
ANY PROBLEMS ALONG THE EASTERN MA COAST. ALONG THE SOUTH
COAST...WINDS WILL NOT BE STRONG ENOUGH TO CAUSE ANY ISSUES. NO
COASTAL PRODUCTS ARE ANTICIPATED OVER THE NEXT 36 HOURS. WORSE CASE
SCENARIO IS THAT VERY MINOR SPLASHOVER MAY OCCUR.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 11 AM THIS MORNING TO 11 PM EDT THIS
     EVENING FOR ANZ230>234-236-251.
     SMALL CRAFT ADVISORY FROM 11 AM THIS MORNING TO 8 AM EDT
     MONDAY FOR ANZ235-237.
     SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 8 PM EDT
     MONDAY FOR ANZ250.
     SMALL CRAFT ADVISORY FROM 11 PM THIS EVENING TO 8 PM EDT
     MONDAY FOR ANZ254>256.

&&

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



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