Area Forecast Discussion
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000
FXUS61 KBOX 020155
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
955 PM EDT SUN MAY 1 2016

.SYNOPSIS...
A WARM FRONT APPROACHES FROM THE SOUTH TONIGHT WITH WAVES OF LOW
PRESSURE RIDING ALONG IT. THE FRONT LIFTS INTO THE REGION ON
MONDAY...THEN SLIDES BACK TO THE SOUTH AND STALLS MONDAY NIGHT ALONG
THE SOUTH COAST. LOW PRESSURE TRAVELS UP ALONG THE FRONT TUESDAY.
THIS WILL BRING ANOTHER PERIOD OF RAIN TO THE REGION. YET ANOTHER
LOW PRESSURE AREA DROPS THROUGH THE GREAT LAKES WEDNESDAY AND
STALLS OVER THE WATERS SOUTH OF NEW ENGLAND FOR THURSDAY THROUGH
THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
10 PM UPDATE...SCATTERED SHOWERS ARE LIMITED MAINLY TO
SOUTHEASTERN MASSACHUSETTS AND RHODE ISLAND AT THIS TIME AND WILL
SLOWLY MOVE OFFSHORE OVERNIGHT. DEWPOINT DEPRESSIONS HAVE NARROWED
QUITE A BIT OVER THE LAST FEW HOURS...BUT REMAIN IN THE 5 TO 10
DEGREE RANGE PARTICULARLY ACROSS THE WESTERN ZONES. EXPECT THEM TO
CONTINUE TO NARROW AS LOW PRESSURE APPROACHES THE REGION. AREAS
CLOSEST TO THE COAST WHERE THE MOISTURE IS THE GREATEST WILL
LIKELY EXPERIENCE AREAS OF FOG AND DRIZZLE OVERNIGHT. PATCHY FOG
AND DRIZZLE IS POSSIBLE FARTHER INLAND BUT BELIEVE THIS WOULDN/T
OCCUR TIL NEAR SUNRISE. OVERNIGHT TEMPS WILL DROP DOWN INTO THE
LOW TO MID 40S.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
MONDAY INTO MONDAY NIGHT...

COMPLEX SYSTEM TOMORROW AND INTO TOMORROW NIGHT. SEVERAL WAVES WILL
MOVE THROUGH THE SOUTHWEST UPPER LEVEL FLOW RESULTING IN PERIODS OF
SHOWERY WEATHER. STILL SOME UNCERTAINTY ON THE EXACT TIMING AND
PLACEMENT OF THE HEAVIEST RAINFALL. FIRST SHORTWAVE WILL PUSH A
LOW PRESSURE SYSTEM EITHER OVER OR JUST NORTH AND WEST OF
SNE...WHERE THE BETTER DYNAMICS ARE LOCATED. HIGHEST CONFIDENCE
FOR PRECIP WILL BE NORTH OF ROUTE 2 AS HEAVIEST PRECIP WILL REMAIN
ACROSS NORTHERN NEW ENGLAND BUT CANNOT RULE OUT THE POTENTIAL FOR
PRECIP TO REACH SOUTH OF THE PIKE.

THIS LOW MAY LIFT THE STALLED FRONT NORTHWARD RESULTING IN TEMPS
WARMING INTO THE LOW 60S ACROSS THE SOUTH COAST. BUT OVERALL
CONFIDENCE IS LOW AS PLACEMENT OF THE FRONT IS SPREAD AMONGST
GUIDANCE...WITH THE GFS BRINGING THE FRONT WELL INTO SOUTHERN NEW
ENGLAND WHILE THE NAM AND EC KEEP IS CLOSER TO THE SOUTH COAST/PIKE.

ANOTHER BREAK IN THE PRECIP LATE MONDAY AFTERNOON AS WEAK RIDGING
MOVES INTO THE REGION. PRECIP LOOKS TO PICK BACK UP AGAIN AS ANOTHER
SHORTWAVE PASSES THROUGH THE FLOW. THIS WAVE WILL SPREAD PRECIP FROM
SW TO NE ALONG THE STALLED FRONTAL SYSTEM...DEPENDING ON WHERE IT
STALLS DURING THE DAY. RIGHT NOW HAVE HIGHEST CONFIDENCE ACROSS THE
SOUTH COAST FOR MEASURABLE PRECIP AS HIGH PRESSURE BUILDS IN ACROSS
NORTHERN NEW ENGLAND. STILL PLENTY OF ROOM FOR THE WAVE TO BRING
PRECIP NORTHWARD.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
BIG PICTURE...

LONGWAVE PATTERN MAINTAINS A TROUGH OVER THE EASTERN USA THROUGH THE
COMING WEEK. THREE SHORTWAVES MOVE THROUGH THIS PATTERN TUESDAY
THROUGH THURSDAY. THE THIRD SHORTWAVE CARVES OUT A CLOSED LOW OVER
THE MID ATLANTIC STATES WHICH THEN DRIFTS EAST OVER THE WATERS SOUTH
OF NEW ENGLAND LATE WEEK. THIS ENTIRE PERIOD WILL FEATURE CLOUDS
AND SHOWERS WITH A SLOW WARMING TREND.

THE DAILIES...

TUESDAY... AS NOTED...SHORTWAVE RACES ACROSS NEW ENGLAND. THE
ASSOCIATED JET GENERATES A WAVE ALONG THE COLD FRONT MOVING TO OUR
SOUTH...AND THAT WAVE MOVES UP THE FRONT TUESDAY. THIS WAVE
FOCUSES A 35-KNOT SOUTH JET TO OVERRUN THE LOW LEVEL NORTHEAST
FLOW OVER NEW ENGLAND...RESULTING IN LOW LEVEL LIFT THAT MOVES
ACROSS DURING THE MORNING. THE BEST LIFT WILL BE ACROSS THE
SOUTHERN COAST AND ISLANDS...WE WILL FEATURE THE HIGHEST POPS IN
THIS AREA. THE NORTHEAST FLOW SHOULD KEEP TEMPS IN THE UPPER 40S
AND 50S WITH WARMEST TEMPS IN WESTERN MASS/CT. CLOUDS AND
NORTHEAST FLOW WILL KEEP TUESDAY NIGHT TEMPS IN THE 40S.

WEDNESDAY... SIGNS IN THE UPPER DATA THAT ANOTHER SHORTWAVE...THIS
ONE FROM THE SOUTHERN PLAINS...CRUISES PAST AND GENERATES ANOTHER
WAVE ON THE FRONT. LESS OF A FOCUSED LOW LEVEL JET AND RESULTING
LIFT...BUT FORCING FROM THE UPPER JET SHOULD BE ENOUGH FOR ANOTHER
CHANCE OF SHOWERS. THIS WILL BE IN TWO PARTS. ONE AREA WILL BE
ALONG THE CAPE AND ISLANDS NEAREST THE OFFSHORE WAVE...THE SECOND
WILL BE IN THE INTERIOR UNDER THE RIGHT ENTRANCE REGION OF THE
UPPER JET.

THURSDAY THROUGH SUNDAY... CLOSED UPPER LOW MOVES INTO PLACE OVER
THE MID ATLANTIC STATES WITH SURFACE LOW OFF DELMARVA.  UPPER FLOW
IS SOUTHERLY BRINGING MILDER AIRMASS THROUGH THE WEEKEND. THE UPPER
JET IN THAT SOUTH FLOW WILL ALIGNED JUST EAST OF NEW ENGLAND WITH
OUR AREA UNDER THE LEFT EXIT REGION OF THE JET. THIS SHOULD ALLOW
FORCING OF SCATTERED OR WIDELY SCATTERED SHOWERS THROUGH THE
WEEKEND. WE TREND MAX TEMPS A LITTLE MILDER EACH DAY BUT MAINTAIN
MINS IN THE 40S EACH NIGHT.

&&

.AVIATION /02Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /THROUGH MONDAY NIGHT/...MODERATE CONFIDENCE.

MAINLY VFR CONDITIONS LOWERING TO MVFR TONIGHT. CONDITIONS WILL
CONTINUE TO LOWER TO IFR AFTER 06Z AS STRATUS...PATCHY FOG AND
DRIZZLE DEVELOPS. IFR CONDITIONS WILL LINGERING INTO EARLY MON
BEFORE CONDITIONS IMPROVE TO MVFR. PERIODS OF RAIN AND DRIZZLE
THROUGH THE PERIOD.

KBOS TERMINAL...HIGH CONFIDENCE IN TRENDS...LOWER CONFIDENCE IN
DETAILS.

KBDL TERMINAL...HIGH CONFIDENCE IN TRENDS...LOWER CONFIDENCE IN
DETAILS.

OUTLOOK /TUESDAY THROUGH FRIDAY/... MODERATE CONFIDENCE

TUESDAY-WEDNESDAY... IFR TUESDAY IN AREAS OF RAIN AND FOG. BEST
CHANCE FOR THIS WILL BE SOUTH OF THE MASS PIKE.

THURSDAY-FRIDAY...AREAS OF MVFR/IFR IN SHOWERS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /THROUGH MONDAY NIGHT/...HIGH CONFIDENCE.

OVERALL QUIET BOATING WEATHER AS WINDS SHIFT MORE TO AN EASTERLY
DIRECTION. PERIODS OF RAIN...DRIZZLE AND FOG WILL PERSIST THROUGH
THE ENTIRE PERIOD. SEAS WILL BUILD ACROSS THE SOUTH COAST TONIGHT
TO 5 FEET RESULTING IN SCA. AS THE WINDS TURN MORE NORTHEASTERLY
TOMORROW...SEAS ALONG THE EASTERN OCEAN WATERS WILL PICK UP ABOVE
5 FEET. SCA WILL CONTINUE FOR THOSE WATERS AS WELL INTO MONDAY
NIGHT.

OUTLOOK /TUESDAY THROUGH FRIDAY/... MODERATE CONFIDENCE

SURFACE FLOW IS EASTERLY...MOSTLY NORTHEAST...THROUGH THE PERIOD
WITH SPEEDS 15 KNOTS OR LESS. EVEN WITH A PERSISTENT DIRECTION SEA
HEIGHTS ON MOST OF THE WATERS WILL REMAIN BELOW 5 FEET. THE BEST
CHANCE OF 5 FOOT SEAS WILL BE ON THE OUTER WATERS WHERE HEIGHTS WILL
VARY BETWEEN 3 AND 5 FEET.  VSBYS WILL BE POOR AT TIMES TUESDAY WITH
RAIN AND FOG. VSBYS WEDNESDAY THROUGH FRIDAY MAY LOWER AT TIMES IN
SHOWERS.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 8 AM MONDAY TO 8
     AM EDT TUESDAY FOR ANZ250-254.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 5 PM MONDAY TO 2
     AM EDT TUESDAY FOR ANZ251.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 8 AM EDT MONDAY
     FOR ANZ256.

&&

$$
SYNOPSIS...WTB/DUNTEN
NEAR TERM...RLG
SHORT TERM...DUNTEN
LONG TERM...WTB
AVIATION...WTB/DUNTEN
MARINE...WTB/DUNTEN



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