Area Forecast Discussion
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000
FXUS61 KBOX 150748
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
348 AM EDT MON SEP 15 2014

.SYNOPSIS...
HIGH PRESSURE FROM NORTHERN NEW ENGLAND TO PENNSYLVANIA WILL SLIDE
SOUTHEASTWARD ACROSS THE REGION TODAY AND OFF THE COAST TONIGHT.
A COLD FRONT WILL MOVE ACROSS THE AREA LATE MONDAY NIGHT AND
TUESDAY MORNING BRINGING A ROUND OF SHOWERS...THEN CLEARING.
MAINLY DRY BUT COOLER THAN NORMAL WEATHER FOLLOWS NEXT WEDNESDAY
THROUGH SATURDAY. TEMPERATURES THEN LIKELY MODERATE TO NEAR NORMAL
BY NEXT SUNDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
330 AM UPDATE...

SKY COVER IS A BIT OF A TRICKY FORECAST THIS MORNING. THE RAP
MODEL RH AT 925 MB HAS THE BEST HANDLE ON EXTENSIVE LOW
CLOUDINESS THAT HAS FORMED IN THREE MAIN AREAS...CENTRAL AND
EASTERN NY STATE...CAPE COD AND PLYMOUTH COUNTY...AND EAST COAST
OF NH. SCATTERED LOW CLOUDS HAD FORMED OVERNIGHT IN OTHER
AREAS...SUCH AS WORCESTER COUNTY AS WELL. THE CLOUDS SEEM TO BE
THE RESULT OF A COLD POOL IN THE 850-700 MB LAYER MOVING ACROSS
EASTERN NY AND SOUTHERN NEW ENGLAND. THE TEMPERATURES IN THAT
LAYER COOL UNTIL ABOUT 15-18Z AND THEN THEY BEGIN TO WARM ACROSS
SOUTHERN NEW ENGLAND.

CLOUDS HAVE BASES MAINLY 4000-5000 FT IN EASTERN NY AND THUS
SHOULD MAKE IT OVER THE BERKSHIRES. HAVE INCREASED SKY COVER TO
60-70 PCT IN MUCH OF SNE...ESPECIALLY N OF THE MA PIKE FOR THE
EARLY TO MID MORNING HOURS. IN ADDITION...AM EXPECTING CLOUD COVER
TO BECOME WIDESPREAD OVER THE WATER ALONG THE E COAST OF MA AS THE
COLDER AIR MOVES OVER THE RELATIVELY WARMER WATERS...BREAKING UP
THIS AFTERNOON. AGAIN...A TRICKY FORECAST.

BY THIS AFTERNOON MOST AREAS SHOULD BECOME PARTLY TO MOSTLY SUNNY
AND THUS THE HIGH TEMPERATURE FORECAST SHOULD STILL BE ABOUT AS
FORECAST PREVIOUSLY...MAINLY MID AND UPPER 60S EXCEPT NEAR 70 IN
INTERIOR SE MA. LIGHT WINDS. SHOULD SEE SOME LIGHT SEA BREEZES
DEVELOP ALONG E COASTAL MA AND SOUTHERN RI IN THE AFTERNOON.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
TONIGHT...DRY WEATHER IS EXPECTED UNTIL WELL AFTER MIDNIGHT AS
HIGH PRESSURE MOVES OFFSHORE. A COLD FRONT TRAILING FROM LOW
PRESSURE IN NORTHERN QUEBEC WILL APPROACH WESTERN NEW ENGLAND LATE
TONIGHT. SHOWERS WILL BECOME LIKELY TOWARD DAYBREAK IN WESTERN MA
AND SOUTHWEST NH AND THERE IS A CHANCE OF SHOWERS ELSEWHERE.
THERE IS ALSO POTENTIAL FOR SOME AREAS OF FOG. LIGHT SOUTHWEST
WINDS AND INCREASING CLOUD COVER WILL PREVENT TEMPERATURES FROM
BOTTOMING OUT LIKE THEY DID THIS MORNING. EXPECTING LOWS IN THE
MID 40S TO MID 50S.

TUESDAY...

A WEAK LOW PRESSURE AREA MAY DEVELOP SOUTH OF NEW ENGLAND ALONG
THE COLD FRONT THAT WILL BE PASSING THROUGH. THE FRONT AND
ASSOCIATED LOW PRESSURE WILL EXIT THE COAST IN THE MID TO LATE
AFTERNOON. SCATTERED SHOWERS IN THE MORNING WILL END AND SKIES
SHOULD BECOME PARTLY SUNNY AS THE DAY PROGRESSES. RAINFALL AMOUNTS
SHOULD BE LESS THAN ONE QUARTER OF AN INCH...ALTHOUGH THE 00Z
ECMWF RUN HAS AS MUCH AS 0.4 INCHES IN A FEW SPOTS. HIGHS AGAIN
MAINLY 65 TO 70.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...

HIGHLIGHTS...

* MAINLY DRY WEATHER WITH BELOW NORMAL TEMPS WED THROUGH SAT
* FROST POTENTIAL FOR PORTIONS OF INTERIOR EARLY FRI/SAT MORNING/S
* SHORT LIVED MILDER WEATHER LOOKS TO RETURN BY SUNDAY.

OVERVIEW...

00Z MODEL GUIDANCE IS IN VERY GOOD AGREEMENT SYNOPTICALLY WITH JUST
MINOR DIFFERENCES AT THE SURFACE. OVERALL...MEAN TROUGH OVER THE
NORTHEAST PORTION OF THE NATION WILL PERSIST THROUGH MOST OF THE
UPCOMING WEEK BEFORE LIFTING INTO THE MARITIMES BY NEXT WEEKEND.
GUIDANCE SHOWS A BRIEF WARM-UP SUN/MON HOWEVER LOOKS TO BE SHORT-
LIVED AND THE TROUGH WILL ONCE AGAIN REESTABLISH ITSELF BY NEXT
WEEK.

SINCE GUIDANCE IS IN GOOD AGREEMENT...USED A BLEND OF DETERMINISTIC
AND ENSEMBLES FOR THIS FORECAST.

DETAILS...

TUESDAY NIGHT INTO WEDNESDAY NIGHT...

DRIER AND COOLER AIR WILL MOVE IN BEHIND THE FRONT TUE NIGHT AS HIGH
PRESSURE BUILDS ACROSS NEW ENGLAND. SKIES SHOULD GENERALLY BECOME
MOSTLY CLEAR ALLOWING FOR TEMPS TO RADIATE OUT OVERNIGHT. ANTICIPATE
TEMPS TO BE BELOW AVERAGE WITH LOWS IN THE LOW TO UPPER 40S AND
HIGHS BARELY REACHING 70 IN SPOTS.

THURSDAY NIGHT INTO SATURDAY...

A DRY COLD FRONT WILL MOVE ACROSS THE REGION ON THURSDAY REINFORCING
THE DRY...COOL AIR ALREADY IN PLACE. THERE IS A LOW PROBABILITY OF A
SPOT SHOWER WHEN THE FRONT MOVES THROUGH BUT DUE TO LACK OF
MOISTURE KEPT OUT OF THE FORECAST FOR NOW.

CANADIAN HIGH PRESSURE BUILDS INTO THE REGION THURSDAY NIGHT LASTING
INTO SATURDAY. THIS HIGH WILL KEEP TEMPS BELOW AVG FOR THIS TIME OF
YEAR. LOW TEMPS WILL BE IN THE 30S ACROSS THE NORMALLY COOLER
OUTLYING AREAS OF SOUTHWEST NH/WESTERN MA...WHERE FROST HEADLINES
WILL LIKELY BE REQUIRED EARLY FRI/SAT MORNING/S.  THE REST OF THE
REGION SHOULD SEE LOWS MAINLY IN THE 40S.

SUNDAY INTO MONDAY...

HIGH PRESSURE MOVING OFF THE COAST SATURDAY NIGHT WILL ALLOW FOR
RETURN FLOW AND WARMER MID LEVEL AIR TO MOVE INTO THE REGION.

HIGHS SHOULD TOP OUT WELL INTO THE MID 70S ON SUNDAY AND MONDAY.
MOST OF THE FORCING FOR ORGANIZED PRECIP SHOULD REMAIN TO OUR NORTH
AND WEST OVER THIS TIME...BUT CAN/T RULE OUT A FEW SPOT SHOWERS IN
THE WARM ADVECTION PATTERN. AT THIS TIME...WILL JUST INCLUDE SLIGHT
CHANCE POPS.

&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

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

TODAY...MODERATE CONFIDENCE. MAINLY VFR. AREAS OF CEILINGS MAINLY
BETWEEN 3000 AND 5000 FT ESPECIALLY THIS MORNING...SPREADING
EASTWARD FROM EASTERN NY AND THE BERKSHIRES AND ALSO OVER CAPE COD
AND THE ISLANDS. CLOUDS FORECAST TO BREAK UP THIS AFTERNOON.

TONIGHT...MODERATE CONFIDENCE. VFR EXCEPT AREAS OF MVFR MAINLY
CAPE COD AND ISLANDS. MVFR/IFR CONDITIONS DEVELOPING IN SHOWERS
AFTER ABOUT 08Z IN NW MA SW NH. LOW RISK OF PATCHY MVFR FOG
INLAND.

TUESDAY...MODERATE CONFIDENCE. SHOWERS WITH MVFR TO PERHAPS EVEN
LOCALLY IFR CONDITIONS EXPECTED IN THE MORNING. CONDITIONS IMPROVE
TO VFR FROM WEST TO EAST DURING THE AFTERNOON.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY.

TUESDAY NIGHT THROUGH FRIDAY...HIGH CONFIDENCE.
VFR CONDITIONS EXPECTED OTHER THAN A TOUCH OF BRIEF EARLY MORNING
PATCHY GROUND FOG IN THE TYPICALLY PRONE LOCATIONS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

TODAY THROUGH TUESDAY...HIGH CONFIDENCE. LIGHT WINDS AND GOOD
VISIBILITY THROUGH MOST OF MONDAY NIGHT AS HIGH PRESSURE MOVES
ACROSS THE WATERS. THERE IS A CHANCE OF SHOWERS VERY LATE MONDAY
NIGHT AND TUESDAY AS A COLD FRONT MOVES ACROSS THE WATERS AND A
WAVE OF LOW PRESSURE PASSES THROUGH. SEAS COULD BUILD TO NEAR
5 FT LATE TUE AFTERNOON IN THE SOUTHEASTERN OUTER WATERS
OTHERWISE WINDS AND SEAS WILL BE WELL BELOW SCA THRESHOLDS.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...

TUESDAY NIGHT AND WEDNESDAY...MODERATE TO HIGH CONFIDENCE.
A DEPARTING COLD FRONT WILL SWITCH THE WINDS TO THE NW AND GUST UP
TO 20 KNOTS. SEAS AS WELL WILL INCREASE IN RESPONSE AND WILL REACH
AT OR ABOVE 5FT ON THE OUTER WATERS. SCA MAY BE NEEDED.

THURSDAY AND FRIDAY...MODERATE TO HIGH CONFIDENCE.  A REINFORCING
COLD FRONT WILL MOVE THROUGH THE REGION ON THU.  MARGINAL SCA SEAS
AND NORTHERLY WIND GUSTS TO 25 KNOTS EXPECTED TO DEVELOP LATE THU
INTO FRI ACROSS SOME OF THE OUTER-WATERS.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...FROST ADVISORY UNTIL 7 AM EDT THIS MORNING FOR MAZ002-003-008.
NH...FROST ADVISORY UNTIL 7 AM EDT THIS MORNING FOR NHZ011-015.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...DUNTEN/GAF
NEAR TERM...GAF
SHORT TERM...GAF
LONG TERM...DUNTEN
AVIATION...DUNTEN/GAF
MARINE...DUNTEN/GAF


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