Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
144 PM EDT SAT APR 25 2015

.SYNOPSIS...
UNSEASONABLY COOL WEATHER CONTINUES THROUGH THIS WEEKEND WITH 
SPOTTY SHOWERS OR SPRINKLES. PERIODS OF UNSETTLED WEATHER AND
BELOW NORMAL TEMPERATURES WILL CONTINUE THROUGH MOST OF NEXT 
WEEK AS WELL.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
145 PM UPDATE...SATELLITE IMAGERY SHOWS SOME MID LEVEL CLOUDS
STREAMING INTO NORTHEAST MASSACHUSETTS. THIS IS ASSOCIATED WITH A
MID LEVEL SHORTWAVE ROTATING AROUND THE UPPER LOW EAST OF SOUTHERN
NEW ENGLAND. TEMPERATURES HAVE CLIMBED INTO THE LOW TO MID 50S
ACROSS MUCH OF SOUTHERN NEW ENGLAND. EXCEPTIONS ARE PORTIONS OF
THE OUTER CAPE AND ISLANDS WHERE TEMPERATURES REMAIN IN THE UPPER
40S. GUSTY WINDS CONTINUE WITH MOST GUSTS AROUND 20 TO 25 MPH.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
WEAK RIDGE BUILDS OVER SOUTHERN NEW ENGLAND TONIGHT...PROVIDING
CLEARING SKIES AND LIGHT WINDS. RADIATIONAL COOLING WITH DEW
POINTS IN THE 30S...SO MINIMUM TEMPERATURES SHOULD BE IN THE 30S
ONCE MORE.

FOR SUNDAY...THE UPPER LOW IS EXPECTED TO MOVE SLIGHTLY CLOSER TO
OUR REGION. THUS WE WILL BE IN A MORE FAVORABLE POSITION FOR
DIURNAL CLOUDS AND SHOWERS. SO...AS HAS BEEN THE CASE OVER THE
LAST SEVERAL DAYS...SKIES SHOULD START OFF PARTLY TO MOSTLY SUNNY.
THEN CLOUDS DEVELOP ALONG WITH A FEW SPOTTY SHOWERS...ESPECIALLY
NEAR AND NORTH OF THE MASS PIKE. EXPECTING MAX TEMPERATURES TO BE
MAINLY IN THE 50S. IF A LITTLE MORE SUNSHINE WORKS THROUGH THE
CLOUDS ACROSS THE LOWER CT VALLEY...READINGS MAY TOUCH 60 IN A FEW
SPOTS THERE.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...

* BELOW NORMAL TEMPERATURES THROUGH NEXT WEEK
* SCATTERED DIURNAL SHOWERS MONDAY AND TUESDAY
* HIGH PRESSURE ON WEDNESDAY
* LOW CONFIDENCE ON COASTAL SYSTEM THURS/FRIDAY

OVERVIEW...

STRETCHED CLOSED LOW OVER THE REGION WILL BRING SEVERAL SHORTWAVES 
THROUGH THE FLOW MONDAY AND INTO EARLY TUESDAY. NORTHERN STREAM 
SHORTWAVE APPEARS TO PUSH CENTRAL CONUS RIDGE TOWARDS THE NORTHEAST 
KICKING THIS LOW OUT TO SEA BY WEDNESDAY. 

BEYOND THIS PORTION OF THE FORECAST IS UNCERTAIN AS GUIDANCE 
CONTINUES TO SPLIT. OVERALL APPEARS UNSETTLED WEATHER AND BELOW 
NORMAL TEMPS CONTINUE AS BLOCKING PATTERN PERSIST...SUPPORTED BY     
-NAO/-AO/+PNA. BOTH MODELS AGREE IN BREAKING THE RIDGE DOWN FAIRLY 
QUICKLY ON WEDNESDAY. AMONG THE OPERATIONAL MODELS THE PAST COUPLE 
ECMWF RUNS AND NEW 00Z UKMET SEEM TO FORM ONE CLUSTER THAT IS QUITE 
AGGRESSIVE WITH THE DEPTH/CLOSURE OF ENERGY FROM THE GREAT LAKES  
INTO MID ATLC...AND STILL WITH VERY DIFFERENT SFC SOLNS...WHILE SOME 
RECENT GFS RUNS AND THE 00Z/24 ECMWF WERE MOST PRONOUNCED IN 
BRINGING TRAILING NERN PAC AND/OR CANADIAN ENERGY ACROSS THE 
NORTHEAST AS A CONCENTRATED UPR LOW LATE IN THE PERIOD.  THE LATTER 
FEATURE WOULD BRING DEEP SFC LOW PRES CLOSE TO NEW ENGLAND OR AT 
LEAST THE CANADIAN MARITIMES AS IN THE THE NEW 00Z GFS. REGARDLESS 
BOTH CAMPS CONTINUE TO PUT THE EASTERN CONUS IN A DEEP TROUGH AT THE 
END OF THE WEEK INTO EARLY NEXT WEEKEND. THEREFORE FELT ENSEMBLE 
GUIDANCE WAS BEST FOR THE WORK WEEK FORECAST.

DETAILS...

* MONDAY INTO TUESDAY...MODERATE CONFIDENCE. 
 
THE UPPER LEVEL LOW WILL CONTINUE TO SPIN BRINGING ITS COOL POOL 
OVER EASTERN NEW ENGLAND. CHANCES OF PRECIP HAS INCREASED...ESP ON 
MONDAY AS A POTENT SHORTWAVE MOVES THROUGH THE FLOW FROM THE NORTH. 
EXPECT SCT DIURNAL SHOWERS AS COLD POOL ALOFT WILL BE SITTING OVER 
THE REGION. PRECIP CHANCES ARE SLIGHTLY LOWER ON TUESDAY AS COLD 
POOL AND UPPER LEVEL LOW BEGIN TO MOVE OFFSHORE...ESP LATE IN THE 
DAY. TEMPERATURES APPEAR TO BE AROUND 10 DEGREES BELOW NORMAL ON 
MONDAY AND ABOUT 5 DEGREES BELOW NORMAL ON TUESDAY. 

* WEDNESDAY...MODERATE CONFIDENCE.
 
DIGGING TROUGH ACROSS THE CENTRAL CONUS WILL PUSH RIDGE OVER THE 
REGION. THIS WILL GIVE SOUTHERN NEW ENGLAND A BREAK IN PRECIP AND 
TEMPS NEAR NORMAL. STILL CANNOT RULE OUT A DIURNALLY DRIVEN SHOWER 
THANKS TO PERSISTENT NORTHERLY FLOW. 

* THURSDAY AND BEYOND...LOW CONFIDENCE. 

STILL SOME UNCERTAINTY IN THIS PORTION OF THE FORECAST. EVERYTHING 
IS DEPENDENT ON HOW THE CUT-OFF LOW IN THE DESERT SOUTHWEST AND 
DIGGING NORTHERN STREAM WAVES BEHAVES.  REGARDLESS APPEARS DEEP 
TROUGH WILL DEVELOP PUTTING SOUTHERN NEW ENGLAND BACK BELOW NORMAL 
FOR TEMPS WITH AN INCREASE IN UNSETTLED WEATHER. STILL WATCHING THE 
DEVELOPMENT OF A COASTAL LOW ON THURSDAY/FRIDAY. BOTH THE GFS AND EC 
HAVE PUSHED THE LOW OUT TO SEA...OR FOCUSED ON THE MID-ATLANTIC 
WHERE THE ENSEMBLES KEEP IT NEAR SOUTHERN NEW ENGLAND. STILL A LOT 
OF UNCERTAINTY AND WILL NEED TO WAIT UNTIL MODELS CAN GET A BETTER 
SAMPLE ON THE SHORTWAVES WHEN THEY COME OFF THE PACIFIC.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

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

.SHORT TERM /THROUGH SUNDAY/...

THROUGH 00Z...HIGH CONFIDENCE. VFR. NW WINDS GUSTING AROUND 20
KNOTS.

TONIGHT...HIGH CONFIDENCE. VFR WITH LIGHT WINDS.

SUNDAY...HIGH CONFIDENCE. VFR WITH LIGHT WINDS. SEA BREEZES
LIKELY. POSSIBLE BRIEF MVFR IN SPOTTY SHOWERS.

SUNDAY NIGHT...HIGH CONFIDENCE. VFR WITH LIGHT WINDS. POSSIBLE
BRIEF MVFR IN SPOTTY SHOWERS.

KBOS TAF...HIGH CONFIDENCE IN OVERALL TAF. LOW CONFIDENCE IN LATE
SEA BREEZE DEVELOPMENT. 

KBDL TAF...HIGH CONFIDENCE IN OVERALL TAF.

OUTLOOK...MONDAY THOUGH WEDNESDAY...

MONDAY INTO TUESDAY...MODERATE CONFIDENCE. VFR WITH MVFR CONDITIONS 
IN SCT SHOWERS. SEA BREEZE DEVELOPMENT IS POSSIBLE ALONG THE EAST 
COAST.

WEDNESDAY...MODERATE CONFIDENCE. VFR CONDITIONS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...

WEST-NORTHWEST WINDS GUST TO 20 KT...WITH A FEW GUSTS TO 25 KT
OFFSHORE. SEAS LINGER NEAR 5 FEET ON THE OUTER WATERS THIS
MORNING...THEN SUBSIDE.

TONIGHT AND SUNDAY...WINDS AND SEAS BELOW SMALL CRAFT ADVISORY
CRITERIA. EXPECT NW WINDS TO SHIFT TO NE SUNDAY...BUT REMAIN
BELOW 15 KT. SEA BREEZES LIKELY SUNDAY.

OUTLOOK...MONDAY THOUGHT WEDNESDAY...

MONDAY THROUGH TUESDAY...HIGH CONFIDENCE. UPPER LEVEL LOW WILL 
CONTINUE TO SPIN ACROSS THE NORTHEAST. HIT OR MISS SHOWERS POSSIBLE 
DURING THE DAY. WIND AND SEAS TO REMAINS BELOW SCA ON SUNDAY. POTENT 
COLD POOL WILL FILTER IN FROM THE NORTH CREATING STRONG CAA AN 
INCREASE WINDS/SEAS FOR MONDAY AND TUESDAY. SCA MAY BE NEEDED. 

WEDNESDAY...MODERATE CONFIDENCE. HIGH PRESSURE WILL BUILD OVER THE 
REGION FROM THE NORTH KEEPING SEAS AND WINDS BELOW SCA.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

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

National Weather Service Glossary of Abbreviations