Area Forecast Discussion
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199
FXUS61 KBOX 030205
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
1005 PM EDT MON MAY 2 2016

.SYNOPSIS...
DRY WEATHER GIVES WAY TO A FAST MOVING LOW PRESSURE SYSTEM
OVERNIGHT. THE LOW WILL BRING A PERIOD OF RAIN OVERNIGHT INTO
TUESDAY MORNING...ESPECIALLY SOUTH OF THE MASSACHUSETTS TURNPIKE.
THE RAIN SHOULD BE OVER FOR MOST BY TUESDAY AFTERNOON...BUT IT
WILL REMAIN RATHER CLOUDY AND COOL. ONE OR MORE WAVES OF LOW
PRESSURE PASS SOUTH OF THE REGION WEDNESDAY BRINGING MORE SHOWERS.
A CLOSED UPPER LOW DEVELOPS OVER THE APPALACHIANS THURSDAY AND
DRIFTS SOUTH OF NEW ENGLAND FRIDAY AND SATURDAY. A COLD FRONT
SWINGS THROUGH NEW ENGLAND SUNDAY...FOLLOWED BY HIGH PRESSURE AND
DRIER WEATHER MONDAY.

&&

.NEAR TERM /UNTIL 1 AM TUESDAY MORNING/...

10 PM UPDATE ...

NOT MUCH CHANGE FROM PREVIOUS FORECAST. NEXT BATCH OF RAIN
CURRENTLY OVER MID ATLC REGION INTO SOUTHEAST PA AND SOUTHERN NJ.
THIS WILL OVERSPREAD SOUTHERN NEW ENGLAND BETWEEN 06Z AND 09Z FROM
SW TO NE. THIS WILL RESULT IN A WET AND SLOW MORNING COMMUTE WITH
THE STEADIEST AND HEAVIEST RAIN ACROSS CT/RI AND SOUTHEAST MA TUE
MORNING. GIVEN PREVIOUS FORECAST MATCHING UP WELL WITH LATEST
SATELLITE AND RADAR TRENDS...NOT MUCH CHANGE WITH THIS FORECAST
UPDATE. EARLIER DISCUSSION BELOW.

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

LOTS OF CLOUDS AND PATCHY DRIZZLE IN PLACE. THIS SHOULD CONTINUE
THROUGH THE NIGHT DUE TO LOW LEVEL MOISTURE REMAINING TRAPPED
BENEATH AN INVERSION. LOW TEMPS WILL BE IN THE 40S AND AREAS OF
FOG ARE EXPECTED ESPECIALLY ON THE COAST. MINOR CHANGES MADE AT
THE EVENING UPDATE BUT OTHERWISE THE FORECAST REMAINS ON TRACK.

&&

.SHORT TERM /1 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...

*** PERIOD OF STEADY RAIN EXPECTED ALONG AND SOUTH OF MA TURNPIKE
AFTER MIDNIGHT INTO TUESDAY MORNING PARTICULARLY NEAR THE SOUTH
COAST ***

OVERNIGHT INTO TUESDAY MORNING...

ANOTHER WAVE OF LOW PRESSURE OVER THE MID ATLANTIC STATES WILL LIFT
NORTHEAST AND PASS SOUTH OF SOUTHERN NEW ENGLAND OVERNIGHT INTO
TUESDAY MORNING.  BOTH THE GFS/NAM SHOW A DECENT BAND OF MID LEVEL
FRONTOGENESIS/OMEGA SOUTH OF THE MA TURNPIKE AND PARTICULARLY NEAR
THE SOUTH COAST.

WITH ALL THAT SAID...EXPECT A BAND OF RAIN TO OVERSPREAD AREAS ALONG
AND SOUTH OF THE MA TURNPIKE TOWARD DAYBREAK.  THE RAIN MAY BRIEFLY
BE HEAVY AT TIMES...ESPECIALLY NEAR THE SOUTH COAST WHERE THE BEST
FORCING/LIFT WILL BE LOCATED.  ALONG THE SOUTH COAST...RAINFALL
AMOUNTS OF 0.50+ INCHES ARE POSSIBLE.  MEANWHILE...NORTH OF THE MA
TURNPIKE AND ESPECIALLY NEAR THE NH BORDER...A PERIOD OF SHOWERS
IS POSSIBLE BUT RAINFALL AMOUNTS WILL BE MUCH LIGHTER.

TUESDAY AFTERNOON...

LOW PRESSURE WILL HAVE PASSED WELL TO OUR EAST TUE AFTERNOON...SO
MAINLY DRY WEATHER OTHER THAN PERHAPS A FEW LINGERING SHOWERS ACROSS
THE FAR SOUTHEAST NEW ENGLAND COAST.  HOWEVER...LOW LEVEL MOISTURE
TRAPPED BENEATH THE INVERSION WILL HANG TOUGH WITH LIGHT NORTH TO
NORTHEAST WINDS. THE RESULT WILL BE ANOTHER DREARY DAY WITH HIGHS IN
THE 50S AND ITS POSSIBLE PORTIONS OF THE EASTERN MA COAST STAY IN
THE UPPER 40S.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...

BIG PICTURE...

LONGWAVE SCALE SHOWS TROUGH EAST/RIDGE WEST FOR MUCH OF THE FORECAST
PERIOD. PROGRESSIVE NORTHERN STREAM STAYS ACROSS CANADA MUCH OF THE
WEEK WHILE FLOW ACROSS THE USA REMAINS BLOCKY WITH CLOSED LOWS OVER
THE PACIFIC AND ATLANTIC COASTS AND A WEAKER RIDGE OVER THE PLAINS.

SHORTWAVES MOVE THROUGH THE EASTERN USA CLOSED LOW. THEN OVER THE
WEEKEND A SHORTWAVE IN THE NORTHERN STREAM DIGS INTO THE LONGWAVE
TROUGH. THIS KICKS OUT THE ATLANTIC CLOSED LOW AND ESTABLISHES A NEW
CLOSED LOW OVER THE MARITIMES.

THIS REMAINS AN UNSETTLED PATTERN FOR NEW ENGLAND THROUGH THE
WEEKEND A TREND TO DRIER WEATHER EARLY NEXT WEEK.

THE DAILIES...

TUESDAY NIGHT-WEDNESDAY... SOUTHWEST UPPER FLOW WITH SEVERAL JET
STREAKS MOVING OVERHEAD OF NEW ENGLAND. STATIONARY FRONT REMAINS
OFFSHORE. THIS IS THE RECIPE FOR ONE OR MORE SURFACE LOWS
RIPPLING UP THE FRONT AND PASSING TO OUR SOUTH. LOW LEVEL FLOW
SOUTH OF THE FRONT REMAINS DIRECTED OUT TO SEA...BUT IF ONE OF
THESE LOWS BECOMES A LITTLE STRONGER THAN DEPICTED THEN IT IS
CONCEIVABLE THAT IT COULD BRIEFLY PULL THE LOW LEVEL FLOW OUT OF
THE SOUTH AND GENERATE SOME LOW LEVEL LIFT/OVERRUNNING ACROSS
SOUTHERN NEW ENGLAND AS IT PASSES. MEANWHILE THE JET STREAKS ALOFT
WILL GENERATE SOME UPPER VENTING. AT A MINIMUM THIS WOULD INDICATE
CHANCE POPS FOR SHOWERS IN SOUTHERN NEW ENGLAND. IF ONE LOW
BECOMES FOCUSSED ALONG THE FRONT THEN HIGHER POPS VALUES /ABOVE
THE 55 PCT LIKELY THRESHOLD/ WOULD BE REASONABLE ALONG THE SOUTH
COAST AND ISLANDS.

THURSDAY THROUGH SATURDAY... CLOSED UPPER LOW TAKES SHAPE OVER
THE APPALACHIANS AND DRIFTS SOUTH OF NEW ENGLAND. COLD POOL ALOFT
ASSOCIATED WITH THE LOW WILL ADVECT OVER OUR AREA AND DESTABILIZE
THE AIRMASS. THIS WILL SUPPORT SCATTERED SHOWERS THROUGH THE
PERIOD.

SUNDAY-MONDAY... NORTHERN SHORTWAVE DIVES SOUTHEAST THROUGH NEW
ENGLAND SUNDAY. THIS DRIVES THE CLOSED LOW OFF TO THE EAST AND
BRINGS A COLD FRONT THROUGH OUR AREA ON SUNDAY. WE SHOULD BE UNDER
THE LEFT EXIT REGION OF THE NORTHWEST UPPER JET...PROVIDING ENOUGH
VENTING TO SUPPORT SCATTERED SHOWERS. HIGH PRESSURE THEN BUILDS IN
WITH DRIER WEATHER FOR MONDAY.

&&

.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /THROUGH TUESDAY/...

10 PM UPDATE ... NOT MUCH CHANGE FROM 00Z TAFS. RAIN REDEVELOPS
ACROSS CT/RI AND MA BETWEEN 06Z AND 09Z FROM SW TO NE WITH
WIDESPREAD RAIN BY 12Z. STEADIEST AND HEAVIEST RAIN WILL FALL OVER
CT/RI AND SOUTHEAST MA TUE MORNING. EARLIER DISCUSSION BELOW.

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

TONIGHT...MODERATE CONFIDENCE. IFR/LIFR CONDITIONS LINGER IN
RI/SOUTHEAST MASS DUE TO LOW CLOUDS/FOG/DRIZZLE. CONDITIONS
FARTHER NORTH AND WEST MAY BRIEFLY IMPROVE TO MVFR.

A BAND OF STEADY RAIN WILL MOVE INTO AREAS ALONG AND SOUTH OF MA
TURNPIKE BETWEEN O6Z AND 12Z. SOME SHOWERS MAY REACH NEAR THE
MA/NH BORDER...BUT THE HEAVIEST RAIN WILL BE NEAR THE SOUTH COAST.

TUESDAY...MODERATE TO HIGH CONFIDENCE.  BULK OF THE RAIN MOVES EAST
OF THE REGION TUE MORNING.  OTHERWISE...MAINLY DRY WEATHER FOR THE
REST OF TUE AFTERNOON BUT MVFR-IFR CONDITIONS WILL LINGER BUT SHOULD
SEE A GRADUAL IMPROVEMENT AT LEAST AWAY FROM THE COAST.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF.  IFR CONDITIONS MAY
BRIEFLY IMPROVE TO MVFR AFTER 00Z THIS EVENING IF WINDS CAN
TEMPORARILY SHIFT TO THE NORTHWEST. IF SO...IFR CONDITIONS PROBABLY
RE-DEVELOP AFTER  8Z WITH THE NEXT BAND OF RAIN.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.  IFR CONDITIONS PROBABLY
IMPROVE TO LOW END MVFR THIS EVENING.

OUTLOOK /TUESDAY NIGHT THROUGH SATURDAY/...MODERATE CONFIDENCE

TUESDAY NIGHT-WEDNESDAY...AREAS OF MVFR/IFR IN SHOWERS AND LOW CIGS.
NORTHEAST WIND 15 KNOTS OR LESS.

THURSDAY THROUGH SATURDAY...VFR WITH AREAS OF MVFR/IFR IN SCATTERED
SHOWERS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

10 PM UPDATE ...

NOT MUCH CHANGE FROM PREVIOUS FORECAST. LOWEST VSBYS OVER EASTERN
MA WATERS BETWEEEN 1 AND 3 MILES. RAIN REDEVELOPS 2 AM TO 5 AM
FROM SW TO NE WITH WIDESPREAD RAIN TUE MORNING. STEADIEST AND
HEAVIEST RAIN OVER THE SOUTH COASTAL WATERS. RAIN TAPERS OFF LATE
MORNING TO EARLY AFTERNOON SW TO NE. EARLIER DISCUSSION BELOW.

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

SHORT TERM /THROUGH TUESDAY/...HIGH CONFIDENCE.

MAIN CONCERN FOR MARINERS WILL BE AREAS OF FOG...MAINLY LATER
TONIGHT INTO TUESDAY.  RELATIVELY WEAK PRESSURE GRADIENT WILL KEEP
MOST WATERS BELOW SMALL CRAFT ADVISORY THRESHOLDS THROUGH TUE
AFTERNOON. HOWEVER...WILL MAINTAIN SCA FOR HAZARDOUS SEAS ACROSS OUR
FAR EASTERN WATERS FOR THE FIRST PART OF THE NIGHT FOR MARGINAL 5
FOOT SEAS. WE MAY NEED ADDITIONAL SCA FOR MARGINAL 5 FOOT SEAS LATER
TUE ACROSS OUR OUTER-WATERS AGAIN...SO SOMETHING LATER SHIFTS WILL
HAVE TO EVALUATE.

OUTLOOK /TUESDAY NIGHT THROUGH SATURDAY/...MODERATE CONFIDENCE

OUTLOOK /TUESDAY NIGHT THROUGH SATURDAY/...MODERATE CONFIDENCE...

NORTHEAST WINDS 15 KNOTS OR LESS. SEAS 5 TO 7 FEET THROUGH THE
PERIOD. SMALL CRAFT ADVISORY FOR SEAS MAY BE NEEDED...MOSTLY ON
THE OUTER WATERS.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 2 AM EDT TUESDAY
     FOR ANZ250-254-255.

&&

$$
SYNOPSIS...WTB/FRANK
NEAR TERM...WTB/FRANK/NOCERA
SHORT TERM...FRANK
LONG TERM...WTB
AVIATION...WTB/FRANK/NOCERA
MARINE...WTB/FRANK/NOCERA



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