Area Forecast Discussion
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000
FXUS61 KBOX 280812
AFDBOX

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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