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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
723 AM EDT SUN MAY 24 2015

.SYNOPSIS...

SOUTHWEST WINDS WILL BRING WARMER AIR INTO SOUTHERN NEW ENGLAND
BEGINNING TODAY. WARM AND MUGGY CONDITIONS BUILD INTO MIDWEEK
AHEAD OF INCREASING CHANCES OF SHOWERS AND THUNDERSTORMS. COULD
REMAIN WET ALL THE WAY THROUGH INTO NEXT WEEKEND.

&&

.NEAR TERM /UNTIL 7 PM THIS EVENING/...

730 AM UPDATE...NO MAJOR CHANGES TO THE FORECAST. 

MID LEVEL CLOUDS DRIFTING ACROSS N NEW ENGLAND IN ADVANCE OF WEAK
SHORT WAVE DIVING SE FROM CANADA. THEY MAY GRAZE N MA. 

OTHERWISE PLENTY OF SUNSHINE EXPECTED TODAY AS CROSS SECTIONS SHOW
DRY AIR THROUGH COLUMN. MIXING LAYER WILL DEEPEN SIGNIFICANTLY
ONCE AGAIN IN RESPONSE TO DAYTIME HEATING...WITH 25-30 MPH GUSTS
EXPECTED NEAR THE S COAST...CAPE COD AND ISLANDS AS WELL AS IN
EASTERN MA WITH 20-25 MPH GUSTS ELSEWHERE. WINDS WILL DIMINISH
TOWARD EVENING AS BOUNDARY LAYER BEGINS TO STABILIZE...ASIDE FROM
S COAST WHERE IT WILL TAKE A BIT LONGER.

HIGHS WILL TOP OUT IN 70S AND LOWER 80S EXCEPT 60S ON S COAST...
CAPE COD AND ISLANDS DUE TO SW FLOW OFF COLDER OCEAN.

&&

.SHORT TERM /7 PM THIS EVENING THROUGH 6 PM MONDAY/...

SW FLOW PERSISTS TONIGHT AND MON AS MODELS BRING WARM FRONT
THROUGH UPSTATE NY AND NORTHERN NEW ENGLAND...WHICH SHOULD BE
FOCUS FOR ANY SHOWERS OR STORMS. 00Z GFS SEEMS OVERDONE IN
BRINGING PRECIPITATION THIS FAR E...ESPECIALLY GIVEN RISING 500 MB
HEIGHTS AND LACK OF DEEP MOISTURE OR APPRECIABLE LIFT OVER OUR
AREA. AS A RESULT WE DO EXPECT TO SEE AN INCREASE IN CLOUDINESS
/MAINLY MID LEVEL/ WITH PERHAPS AN ISOLATED SHOWER OR STORM MON
ACROSS NW MA.

LOWS WILL DROP BACK INTO 50S TONIGHT AND ONCE AGAIN CLIMB INTO
70S/LOWER 80S MON EXCEPT 60S ON S COAST...CAPE COD AND ISLANDS.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...

*/ HIGHLIGHTS...

 - WARM MUGGY AND DRY TUESDAY INTO TUESDAY NIGHT
 - INCREASING SHOWER / THUNDERSTORM POTENTIAL WEDNESDAY - THURSDAY
 - PERHAPS A LULL IN THE WEATHER ON FRIDAY
 - LOOKING POTENTIALLY WET AND ACTIVE FOR NEXT WEEKEND 

*/ DISCUSSION...

FORECAST GUIDANCE STRUGGLING WITH BOTH STRENGTH AND INFLUENCE OF 
RIDGING ACROSS THE E-CONUS AND SUBSEQUENT ALLOWANCE OF N-STREAM 
ENERGY TO SLIP S. AS BEEN THE TREND THE LAST SEVERAL DAYS...THE 
RIDGE DEAMPLIFIES SUBSEQUENT TO THE FLATTENING MARITIME FLOW AND 
RETROGRADING LOW PULLING COOLER AIR CYCLONICALLY SW. THERE IS NOT 
MUCH SUPPORT IN MAINTAINING A RIDGING PATTERN. SO EXPECTATION THRU 
THE WEEK IS FOR N-STREAM ENERGY TO HAVE THE ABILITY TO TROUGH S 
SHIFTING THE CONVERGENT SW-FLOW ALONG WITH THETA-E / INSTABILITY 
AXES INTO NEW ENGLAND. ANTICIPATING INCREASING CHANCES FOR SHOWERS 
AND THUNDERSTORMS ESP ACROSS THE INTERIOR. SHEAR NOT IMPRESSIVE 
COMPARED TO INSTABILITY...SO ECHO PRIOR FORECASTER WITH CONCERN OF 
HEAVY RAIN AS A THREAT. 

WILL KEEP TUESDAY INTO TUESDAY NIGHT DRY. THOUGH THE WARM AND MUGGY 
CONDITIONS POTENTIALLY EXCEEDING CONVECTIVE-TEMPERATURES ACROSS THE 
N AND W MAY YIELD THUNDERSTORMS THAT WOULD PUSH E WITH THE STEERING 
FLOW...FEEL DRY AIR AND SUBSIDENCE WILL ERODE / WEAKEN ANY ACTIVITY 
INTO NEW ENGLAND. THE BETTER FORCING AND SW-CONVERGENT FLOW OF MOIST-
INSTABILITY AXES IS WELL NW AT THIS TIME. LOW-90S POSSIBLE ACROSS 
INTERIOR VALLEYS. EXPECT MARINE STRATUS / FOG ALONG THE S/SE-COAST 
PERHAPS DEVELOPING AS EARLY AS MONDAY NIGHT INTO TUESDAY. 

WEDNESDAY INTO THURSDAY THE RIDGE WEAKENS ALLOWING THE FAVORABLE 
ENVIRONMENT FOR SHOWERS AND THUNDERSTORMS TO SHIFT SE. INCREASING 
POP CHANCES ACCORDINGLY. SOME QUESTION AS TO HOW EFFECTIVELY WE CAN 
DESTABILIZE. COULD BE ISSUES WITH CLOUD COVER SHOULD ACTIVITY ON 
WEDNESDAY EXPECTED MAINLY W DRIFTS E OVERNIGHT INTO THURSDAY. WILL 
CONTINUE WITH WARM AND MUGGY CONDITIONS. LOW-90S POSSIBLE ACROSS 
INTERIOR VALLEYS ESPECIALLY WEDNESDAY. CONTINUED POTENTIAL OF MARINE 
STRATUS / FOG ALONG THE S/SE-COAST. 

FRIDAY COULD BE A LULL WITH DRY AIR AND HIGH PRESSURE IN PLACE IF 
YOU BELIEVE THE GFS OVER THE ECMWF. LOW CONFIDENCE. CONSENSUS OF 
FORECAST GUIDANCE HAS ANOTHER WAVE N PUSHING A FRONTAL BOUNDARY S 
AND STALLING OVER NEW ENGLAND MAKING IT A FOCUS FOR A PROLONGED 
PERIOD OF WET-WEATHER. HAVE SOME DOUBTS WITH CONVERGENT MASS-FIELDS 
N AS SURFACE REFLECTIONS FOCUS S WITH THERMAL-INSTABILITY-MOIST 
AXES. SHOULD HAVE A BETTER IDEA AS WE GET CLOSER IN TIME.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...

FORECASTER CONFIDENCE LEVELS...

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

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

12Z UPDATE...

VFR WITH SW FLOW. 20-25 KT GUSTS LATER THIS MORNING INTO EARLY
EVENING...ESPECIALLY NEAR COAST. CIGS AOA 060 LATE TONIGHT AND
MONDAY WITH AN ISOLATED -SHRA/TSRA POSSIBLE ACROSS NW MA.

KBOS TERMINAL...HIGH CONFIDENCE IN TAF. 
 
KBDL TERMINAL...HIGH CONFIDENCE IN TAF. 

OUTLOOK...MONDAY NIGHT THROUGH THURSDAY NIGHT...

MONDAY NIGHT INTO TUESDAY NIGHT...MODERATE CONFIDENCE. VFR. BREEZY 
SW-FLOW WITH 20-25 KT GUSTS. IFR STRATUS / FOG POSSIBLE ACROSS THE 
S/SE-COAST.

WEDNESDAY INTO THURSDAY NIGHT...MODERATE CONFIDENCE. INCREASING 
CHANCES FOR -SHRA / TSRA. TEMPO MVFR-IFR WITH ANY ACTIVITY. SW-FLOW 
WITH 20 KT GUSTS AT TIMES. IFR STRATUS / FOG REMAINS POSSIBLE ACROSS 
THE S/SE-COAST.

&&

.MARINE...

FORECASTER CONFIDENCE LEVELS...

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

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

730 AM UPDATE...SMALL CRAFT ADVISORY FOR ALL WATERS TODAY. 

STILL SEEING AROUND 20 KT GUSTS ON S COASTAL BAYS / SOUNDS PER
COASTAL BUOYS AND MESONET OBSERVATIONS THIS MORNING...WHERE SCA
REMAINS POSTED. EXPANDED SCA TO INCLUDE ALL WATERS WITH EXPECTED
25 KT GUSTS BEGINNING THIS MORNING AND INTO THIS EVENING...ESP
WITHIN FEW MILES OF SHORE. SEAS WILL BUILD TO 5 FT ON OUTER
WATERS...WHERE SCA REMAINS IN EFFECT THROUGH MIDNIGHT WHEN SEAS
SHOULD SUBSIDE.

INCREASING SW WINDS AGAINST DEPARTING TIDE ON BUZZARDS BAY AND
WESTERN PORTION OF VINEYARD SOUND SHOULD LEAD TO STEEP WAVES...
FIRST THROUGH SUNRISE AND AGAIN THIS AFTERNOON.

GUSTS MAY BE MARGINAL ALONG E MA COAST INCLUDING BOS HARBOR BUT
DECIDED TO INCLUDE THESE AREAS DUE TO INCREASE IN HOLIDAY
RECREATIONAL TRAFFIC.

WINDS AND SEAS DIMINISH TONIGHT. SW FLOW PERSISTS MON BUT GUSTS
ARE EXPECTED TO REMAIN BELOW SCA.

OUTLOOK...MONDAY NIGHT THROUGH THURSDAY NIGHT...

MODERATE CONFIDENCE. PERSISTENT SW-FETCH WITH GUSTS AROUND 20-25 KTS 
AT TIMES. WAVE HEIGHTS IN EXCESS OF 5-FEET MOSTLY ON THE OUTER 
WATERS BUT GETTING INTO THE S INNER SOUNDS. FOG ANTICIPATED LENDING 
TO VISIBILITY RESTRICTIONS.

&&

.FIRE WEATHER...

STILL HAVE CONCERN FOR ELEVATED FIRE WEATHER SPREAD TODAY GIVEN
LOW HUMIDITY /20-30 PERCENT/...GUSTY SW WINDS /20-25 MPH/ AND LACK
OF SIGNIFICANT RAINFALL OVER PAST SEVERAL WEEKS. WE WILL ISSUE
SPECIAL WEATHER STATEMENT TO ADDRESS THIS CONCERN.

PERSISTENT SW FLOW WILL BRING GRADUAL INCREASE IN HUMIDITY THIS
WEEK.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...

CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR 
     ANZ232>235-237.
     SMALL CRAFT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR ANZ230-
     231-236-250-251.
     SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ254>256.

&&

$$

SYNOPSIS...SIPPRELL/JWD
NEAR TERM...SIPPRELL/JWD
SHORT TERM...JWD
LONG TERM...SIPPRELL
AVIATION...SIPPRELL/JWD
MARINE...SIPPRELL/JWD
FIRE WEATHER...WFO BOX STAFF

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