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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
412 AM EDT SAT MAR 28 2015

.SYNOPSIS...
OFFSHORE LOW PRESSURE WILL PASS WELL OFFSHORE BUT SPREAD LIGHT
SNOW AND RAIN SHOWERS INTO SOUTHERN NEW ENGLAND. HIGH PRESSURE
BUILDS OVER THE EASTERN USA WITH DRY WEATHER. ANOTHER BATCH OF
PRECIPITATION IS POSSIBLE LATE SUNDAY NIGHT INTO MONDAY AHEAD OF A
COLD FRONT. FAST MOVING LOW PRESSURE WILL BRING MORE LIGHT RAIN
AND/OR SNOW SHOWERS TUESDAY NIGHT INTO WEDNESDAY. LOW PRES MAY
APPROACH LATE NEXT WEEK WITH MORE PRECIPITATION.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THROUGH 8 AM...
RADAR SHOWS TWO AREAS OF LIGHT PCPN MOVING INTO SOUTHERN NEW
ENGLAND. ONE GLIDES UP FROM THE SOUTHWEST INTO SOUTH COASTAL
SECTIONS...WHILE THE SECOND SWEEPS SOUTHEAST FROM THE ADIRONDACKS
INTO WESTERN MASS. OBSERVATIONS SHOW LIGHT RAIN SHOWERS ON THE
SOUTH COAST AND FLURRIES MOVING FROM NEW YOUR INTO THE BERKSHIRES.
EXPECT LIGHT PCPN TO MOVE DEEPER INTO SOUTHERN NEW ENGLAND EARLY
THIS MORNING. LOW CONFIDENCE ON THE EXACT TIMING...BUT HIGHER
CONFIDENCE ON THE TREND. 

TODAY...
UPPER TROUGH OVER THE GREAT LAKES BRINGS COLD ADVECTION SURFACE
AND ALOFT...DESTABILIZING THE AIRMASS. VERTICAL PROFILES SHOW A
DEEP LAYER OF MOISTURE THROUGH THE DAY ALONG WITH 20-30 MB/HOUR OF
LIFT. LARGE SCALE AND MESOSCALE MODELS HAVE BEEN HINTING AT A
SURFACE TROUGH DEVELOPING OFF THE EAST COAST OF MASS AND THEN
PIVOTING ACROSS EASTERN MASS AND RI. 

ALL OF THIS WOULD SUPPORT DEVELOPING PCPN. THE UPPER TROUGH AND
DESTABILIZATION WOULD FAVOR A CONVECTIVE MODE /SHOWERS/ RATHER
THAN STRATIFORM.

SURFACE TEMPS WOULD SUGGEST RAIN ALONG THE COAST AND AND SNOW
INLAND. TEMPS AT OR ABOVE 950 MB WOULD SUGGEST SNOW ALL AREAS
EXCEPT CAPE COD/ISLANDS. PTYPE AND POTENTIAL ACCUMULATIONS WILL
HINGE ON THESE TEMPERATURES. WE SPECULATE THAT MANY OF THE SNOW
SHOWERS MAY LEAVE A SLUSHY ACCUMULATION...BUT LESS THAN WHAT WE
WOULD HAVE SEEN 1 1/2 MONTHS AGO. THE BEST CHANCE OF
ACCUMULATIONS WILL COME IN THE HILL COUNTRY SUCH AS THE WORCESTER
HILLS IN MASS AND THE HILLS IN NORTHEAST CT/NORTHWEST RI.
ACCUMULATIONS OF AN INCH OR TWO ARE POSSIBLE BY EVENING...BUT
BECAUSE THESE ARE SHOWERS THE ACCUMULATIONS SHOULD NOT BE UNIFORM.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
TONIGHT...LOW CONFIDENCE.
OFFSHORE LOW MOVES OFF THROUGH THE MARITIMES WHILE UPPER TROUGH
MOVES OVERHEAD. THIS MAINTAINS THE POTENTIAL FOR PCPN WHILE
COOLING NIGHTIME TEMPS WOULD FAVOR SNOW OR RAIN CHANGING TO SNOW.
THE PIVOTING SURFACE TROUGH SHOULD MOVE OFFSHORE AFTER MIDNIGHT WITH
ANY PCPN OVER OUR AREA DIMINISHING. BASED ON EXPECTED TEMPS AND
LIGHT PCPN THROUGH THE DAY AND NIGHT WE PROJECT STORM TOTAL OF 1-3
INCHES IN THE HILLS AND AROUND 1 INCH IN THE LOWER TERRAIN.

NORTH WINDS WILL PULL /YET AGAIN/ COLDER THAN NORMAL AIR ACROSS
THE REGION. TEMPERATURES UPSTREAM OVERNIGHT HAVE BEEN IN THE TEENS
AND LOWER 20S. CLOUDS MAY SLOW COOLING A LITTLE...SO WE FAVORED 15
TO 25 DEGREES.

SUNDAY...HIGH CONFIDENCE.
HIGH PRESSURE BUILDS OVER THE EASTERN USA SURFACE AND ALOFT. THIS
SHOULD BRING SUNNY SKIES MOST AREAS. SOME LINGERING CLOUDS ARE
POSSIBLE IN THE MORNING IN EASTERN MASS. TEMPS ALOFT SUGGEST HIGHS
IN THE 30S...BUT WARM ADVECTION LATE IN THE DAY MAY NUDGE VALUES
TO AROUND 40.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...

HIGHLIGHTS...

* A WEAK COLD FRONT WILL MOVE THROUGH ON MONDAY BRINGING SCT SHOWERS
* MODERATING SPRING-LIKE TEMPS INTO NEXT WEEK
* ALBERTA CLIPPER MOVES THROUGH TUESDAY NIGHT INTO WED
* INCREASING CHANCES FOR PRECIP SOMETIME DURING THE EASTER WEEKEND

OVERVIEW...

ACTIVE PATTERN APPEARS TO BE SETTING UP OVER SOUTHERN NEW ENGLAND 
NEXT WEEK. FIRST SYSTEM IS ON MONDAY FOLLOWED BY A WAVE TUESDAY 
NIGHT AND FINALLY A SYSTEM THURS/FRIDAY. OVERALL...A QUICK MOVING 
RIDGE AND ASSOCIATED HIGH WILL DEVELOP ON SUNDAY BEFORE NORTHWEST 
FLOW SETS UP AS RIDGE BUILD OVER THE ROCKIES. THIS WILL ALLOW FOR 
SEVERAL WAVES TO PUSH THROUGH. AS MENTIONED EARLIER...LOW PRESSURE 
SYSTEM WILL MOVE ACROSS NORTHERN NEW ENGLAND DRAGGING A COLD FRONT 
WITH IT ON MONDAY. NEXT AN ALBERTA CLIPPER WILL DIVE INTO SOUTHERN 
NEW ENGLAND BY LATE TUESDAY INTO WEDNESDAY. LASTLY A NORTHERN AND 
SOUTHERN STREAM MERGER APPEARS TO APPROACH THURSDAY/FRIDAY.  

IT IS DIFFICULT TO ANY DETERMINISTIC MODEL OVER ANOTHER SINCE ALL 
FALL WITHIN THE MULTI-CENTER ENSEMBLE SPREAD. NEVERTHELESS... THE 
ECMWF HAS BEEN MORE CONSISTENT WITH SOME...NOT ALL...FEATURES ACROSS 
THE REGION THAN THE GFS AND HAS MORE SUPPORT FROM THE CMC/UKMET. 
NOTHING SHOWS GOOD MULTI-DAY CONTINUITY AND THE TREND HAS BEEN BOTH 
SLOWER AND QUICKER... DEPENDING ON THE SYSTEM OF INTEREST. THEREFOR 
TRENDED TOWARD WPC GUIDANCE FOR THIS FORECAST. 

DETAILS...

* SUNDAY NIGHT INTO TUESDAY...HIGH CONFIDENCE. 

NEXT UPPER LEVEL SHORTWAVE WILL QUICKLY MOVE THROUGH NW FLOW ALOFT 
LATE SUNDAY INTO MONDAY. GUIDANCE SEEMS TO BE IN BETTER AGREEMENT 
WITH THIS SYSTEM KEEPING MOST OF SUN PM DRY AND BRINGING PRECIP 
EARLY MONDAY MORNING. SURFACE LOW ACROSS THE GREAT LAKES WILL PASS 
JUST NORTH OF SNE...DRAGGING ASSOCIATED COLD FRONT WITH IT. TEMPS AT 
THE ONSET LOOK TO BE COOL THEN WARM UP DURING THE DAY ON MONDAY 
PRIOR TO FRONTAL PASSAGE. AT THE ONSET OF PRECIP...EXPECT A FEW SNOW 
SHOWERS...BUT THEN TRANSITIONING TO RAIN FAIRLY QUICKLY AS TEMPS 
WARM UP. MOISTURE IS MARGINAL SO COVERAGE MAY BE MORE SCT ALONG THE 
FRONT. EXPECT VERY MINOR ACCUMULATIONS WITHIN ANY SNOW SHOWERS. 
BEHIND THE FRONT...WESTERLY WINDS WILL BE ON THE INCREASE AND 
GUSTING TO 25-30 MPH. 

TUESDAY WILL BE MOSTLY DRY AS SOUTHERN NEW ENGLAND IS SQUEEZED 
BETWEEN TWO SYSTEMS. WINDS WILL CONTINUE TO GUST THROUGH THE DAY. 
TEMPS WILL BE IN THE MID TO UPPER 40S BUT WITH THE WIND...IT WILL 
FEEL LIKE THE UPPER 30S.  CLOUDS WILL BE ON THE INCREASE THROUGHOUT 
THE DAY AS NEXT SYSTEM APPROACHES. 

* TUESDAY NIGHT INTO WEDNESDAY...MODERATE CONFIDENCE. 

NEXT SHORT WAVE WILL QUICKLY DIVE THROUGH THE FLOW FROM CANADA AND 
MOVE JUST SOUTH OF SOUTHERN NEW ENGLAND. THE EC IS STILL MORE 
AMPLIFIED/STRONGER WITH THIS SYSTEM CUTTING OFF THE 850 MB LOW 
COMPARED TO THE GFS WHICH KEEPS AN OPEN WAVE. THIS HAS ALLOWED FOR 
PRECIP TO BE CLOSER TO SNE WHILE THE GFS PUSHES EVEN FARTHER SOUTH 
IMPACTING THE MID-ATLANTIC. OVERALL BELIEVE THAT LOCATIONS ALONG AND 
SOUTH OF THE PIKE HAVE THE BEST CHANCE TO SEE PRECIP. MODELS ARE 
SIMILAR ON THE TIMING BRINGING PRECIP IN OVERNIGHT AND PUSHING OUT 
BY LATE WED MORNING. THIS WILL ALLOW FOR TEMPS TO BE COOL ENOUGH FOR 
SNOW SHOWERS. WILL NEED TO CONTINUE TO WATCH THE TRENDS WITH THIS 
SYSTEM SINCE IT COULD PRODUCE A QUICK 1-2 INCHES OF SNOW ACROSS THE 
AREA. 

* WEDNESDAY NIGHT INTO FRIDAY...LOW CONFIDENCE IN TIMING. MODERATE 
  CONFIDENCE IN PRECIP OCCURRING. 

WEAK RIDGE WILL FOLLOW BEHIND THE SYSTEM BEFORE NEXT LOW PRESSURE 
IMPACT SOUTHERN NEW ENGLAND EITHER THURSDAY OR FRIDAY. EC IS LESS 
AMPLIFIED AND MORE PROGRESSIVE COMPARED TO THE GFS. STILL PLENTY OF 
TIME TO WATCH THIS SYSTEM AS WELL. BECAUSE OF THE MODEL 
DISCREPANCIES HAVE A LOW CONFIDENCE ON TIMING...BUT BOTH 
DETERMINISTIC AND ENSEMBLE GUIDANCE POINT TOWARDS WET WEATHER 
THURSDAY INTO FRIDAY. LASTLY TEMPS MAY TURN MORE SPRING-LIKE BY 
THURS/FRIDAY AHEAD OF NEXT SYSTEM. 

&&

.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM...TODAY THROUGH SUNDAY

TODAY...
MVFR CIGS MOVING INTO THE SOUTH COAST AND THE BERKSHIRES. VFR IN
BETWEEN. EXPECT A TREND TO MVFR CIGS/VSBYS IN RAIN AND SNOW
SHOWERS WITH OCCASIONAL IFR IN SNOW SHOWERS. 

TONIGHT...
MIXED MVFR/IFR CIGS AND VSBYS CONTINUE EARLY NIGHT...SIMILAR TO
CONDITIONS DURING THE DAY BUT WITH BROADER FAVORING OF SNOW AS
TEMPERATURES COOL. TREND SHIFTS TO VFR AFTER MIDNIGHT AS DRIER AIR
MOVES IN.

SUNDAY...VFR. IFR MAY LINGER NEAR THE CAPE AND ISLANDS IN THE
MORNING BUT WITH THE TREND TO VFR BY AFTERNOON.

KBOS TAF...MODERATE CONFIDENCE IN TAF.

KBDL TAF...MODERATE CONFIDENCE IN TAF.

OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...HIGH CONFIDENCE.
 
SUNDAY NIGHT...LINGERING MVFR ACROSS THE CAPE AND ISLANDS. VFR 
EVERYWHERE ELSE. 

MONDAY...VFR DROPPING TO POSSIBLE MVFR IN SCT RAIN SHOWERS AS WEAK 
COLD FRONT MOVES THROUGH. GUSTY WESTERLY WINDS BEHIND THE FRONT NEAR 
20-25 KTS. 

TUESDAY INTO WEDNESDAY...VFR FOR MOST OF THE PERIOD. MAY SEE MVFR 
SOUTH OF PIKE IN QUICK MOVING RAIN/SNOW SHOWERS. 

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM...TODAY THROUGH SUNDAY

MODERATE CONFIDENCE TODAY AND TONIGHT. HIGH CONFIDENCE SUNDAY.

NORTH WINDS INCREASE AS LOW PRESSURE PASSES WELL OFFSHORE. EXPECT
THESE WINDS WILL FREQUENTLY GUST TO 25 KNOTS ON MOST MASSACHUSETTS
WATERS AND POSSIBLY RI SOUND. GUSTS TO 30 KNOTS POSSIBLE ON THE
OUTER WATERS EAST OF MASS. SEAS WILL BE 5-8 FEET ON ALL EXPOSED
WATERS AND 1 TO 4 FEET ON THE REMAINING WATERS. 

WINDS ON THE NEARSHORE WATERS DIMINISH THIS EVENING WHILE WINDS
FARTHER OFFSHORE MAY TAKE UNTIL LATE TONIGHT TO FALL BELOW 25
KNOTS. UNDER THESE CONDITIONS WE EXPECT SEAS TO REMAIN AT THEIR
DAYTIME LEVELS.

HIGH PRESSURE BUILDS OVER THE WATERS SUNDAY. WINDS AND SEAS SHOULD
DIMINISH AT THAT TIME. LINGERING 5 FOOT SEAS ON THE OUTER WATERS
DURING THE AFTERNOON.

SMALL CRAFT ADVISORIES HAVE BEEN EXPANDED TO ALL WATERS EXCEPT
NARRAGANSETT BAY...AND EXTENDED INTO SUNDAY FOR MOST WATERS.

OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...

MODERATE CONFIDENCE INTO WEDNESDAY.

SUNDAY THROUGH MONDAY...HIGH PRESSURE MOVES OFFSHORE SUNDAY NIGHT AS 
WINDS BACK TO SW. APPROACHING COLD FRONT ON MONDAY WILL INCREASE SEAS 
IN RESPONSE. THIS WILL ALLOW FOR SCA TO CONTINUE THROUGH THE PERIOD. 

TUESDAY...WEAK LULL IN BETWEEN SYSTEMS HOWEVER WINDS WILL BE GUSTY 
ON THE BACKSIDE OF THE FRONT REACHING NEAR 30KTS. THIS WILL KEEP 
SEAS UP ABOVE SCA. 

TUESDAY NIGHT INTO WEDNESDAY...QUICK MOVING SYSTEM WILL MOVE OVER 
SOUTHERN WATERS. THIS WILL KEEP BOTH SEAS AND WINDS ABOVE SCA ON 
TUESDAY NIGHT. HIGH PRESSURE WILL FOLLOW ON WED ALLOWING FOR SEAS 
AND WINDS TO RELAX. 

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 10 PM EDT THIS 
     EVENING FOR ANZ232>234.
     SMALL CRAFT ADVISORY FROM NOON TODAY TO 10 PM EDT THIS EVENING 
     FOR ANZ230.
     SMALL CRAFT ADVISORY UNTIL 3 PM EDT SUNDAY FOR ANZ231-251.
     SMALL CRAFT ADVISORY UNTIL 3 PM EDT SUNDAY FOR ANZ235-237.
     SMALL CRAFT ADVISORY UNTIL 10 PM EDT SUNDAY FOR ANZ250-254>256.

&&

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

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