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Area Forecast Discussion
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000
FXUS61 KBOX 221745
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
145 PM EDT MON SEP 22 2014

.SYNOPSIS...
A DRIER AND LESS HUMID AIRMASS OVERSPREADS THE REGION TODAY BEHIND
A DEPARTING COLD FRONT THIS MORNING...WITH BREEZY CONDITIONS AND
A MIX OF SUN AND CLOUDS. THIS AIRMASS REMAINS OVER THE REGION MUCH
OF THE WEEK YIELDING MILD DAYS AND COOL NIGHTS. BY WEEKS END TEMPERATURES
BEGIN TO WARM WITH POSSIBLE RECORD WARMTH NEXT WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
145 PM UPDATE...
DEWPOINTS HAVE DROPPED INTO THE 40S ACROSS MUCH OF SNE AS GUSTY
W/NW WINDS ADVECT MUCH DRIER AIR INTO THE REGION. SCT DIURNAL CU
HAS DEVELOPED BUT GREATER COVERAGE OF CLOUDS NORTH AND WEST OF
SNE. FORECAST ON TRACK. 

PREVIOUS DISCUSSION...
COLD FRONT OFFSHORE WITH GUSTY WEST WIND USHERING IN MUCH DRIER
AIRMASS AS DEWPOINTS FALL THROUGH THE 50S AND INTO THE 40S.
DIURNAL CU EXPECTED WITH GREATEST COVERAGE IN THE INTERIOR. STRONG
LOW LEVEL CAA...ESPECIALLY WEST WILL KEEP TEMPS IN THE 60S BUT
REACHING INTO THE 70S IN THE COASTAL PLAIN WHERE STRONGER CAA IS
DELAYED UNTIL AFTER 18Z. GOOD MIXING WILL YIELD WIND GUSTS TO
25-30 MPH WITH A FEW HIGHER GUSTS OVER THE ELEVATED TERRAIN.
CURRENT FORECAST ON TRACK SO NO MAJOR CHANGES.

A BUILDING OFFSHORE SWELL TODAY...WILL YIELD HIGH SURF
PARTICULARLY AT SOUTH COASTAL BEACHES TODAY. THEREFORE...WILL
CONTINUE HIGH SURF ADVISORY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
TONIGHT...
COOL DRY AIRMASS SETTLES IN PLACE AS NOSE OF STRONG 1035 HPA HIGH
PRES MOVES IN FROM THE W. IN SPITE OF THIS MORE AUTUMN-LIKE
AIRMASS...MINS MAY NOT BE ABLE TO REALIZE THEIR FULL POTENTIAL.
THE COMBINATION OF LINGERING DIURNAL CU EARLY...AND SFC PRES
GRADIENT TAKING SOME TIME TO FULLY SLACKEN MAY LIMIT RADIATIONAL
COOLING. LOWS IN THE UPPER 30S-MID 40S ARE LIKELY...WITH MINS
CLOSER TO 50 IN THE URBAN SPOTS. THE COLDEST SPOTS ARE LIKELY IN
NW MA AND SW NH. IT/S VERY CLOSE TO FROST THRESHOLDS...BUT WITH
THE MITIGATING FACTORS MENTIONED...NOT CONFIDENT ENOUGH TO ISSUE
FROST ADVISORY AT THIS TIME. THIS WILL HAVE TO BE WATCHED THROUGH
THE DAY.

TUE...
HIGH PRES BEGINS TO CREST ACROSS THE REGION ON TUE.
THEREFORE...MOSTLY SUNNY SKIES ARE EXPECTED. H85 TEMPS HOVER
AROUND +6C...BUT MAY NOT BE FULLY REALIZED UNDER STRONG
SUBSIDENCE INVERSION. THEREFORE...KEEPING HIGHS GENERALLY A DEGREE
OR TWO BELOW NORMAL. MAINLY THE MID 60S TO AROUND 70.

&&

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

* THE 1ST WEEK OF AUTUMN WILL FEATURE MILD DAYS AND COOL NIGHTS 
  FOLLOWED BY POTENTIAL NEAR RECORD WARMTH NEXT WEEKEND 

* HIGH PRESSURE PROVIDES DRY WEATHER THROUGH THE PERIOD

     SYNOPTIC OVERVIEW AND MODEL EVALUATION... 

FAIRLY STRONG TELECONNECTION FOR RIDGING HERE IN THE EAST THIS 
COMING WEEK AND NEXT WEEKEND AS +PNA TRENDS TOWARD NEUTRAL ALONG 
WITH NAO AND AO TRENDING OR REMAINING POSITIVE. DURING THIS TIME THE 
LARGE SCALE FLOW EVOLVES INTO A WEST COAST TROUGH WITH A DOWNSTREAM 
RIDGE OVER THE GREAT LAKES NORTHWARD TOWARD JAMES BAY.  THIS IS A 
WARM AND DRY SETUP FOR NEW ENGLAND. HOWEVER GIVEN THE CHAOTIC NATURE 
OF THE ATMOSPHERE THERE ARE ALWAYS WILDCARDS AT THIS TIME RANGE AND 
THIS CASE IS NO EXCEPTION. 

THE FIRST WILDCARD WILL BE THE DOWNSTREAM MEAN TROUGH OVER THE 
MARITIMES. WILL HAVE TO WATCH IF ANY NORTHERN STREAM IMPULSES 
CLIMBING OVER THE GREAT LAKES RIDGE AND THEN INTO THE MARITIMES 
DRAGS ANY BACKDOOR FRONTS INTO EASTERN NEW ENGLAND. THIS WOULD YIELD 
COOLER TEMPS ESPECIALLY FOR EASTERN MA. THE OTHER WILDCARD WILL BE 
MOISTURE AND JET ENERGY THAT BREAKS OFF OVER THE SOUTHEAST STATES 
FROM THE MID LEVEL TROUGH MOVING ACROSS THE EASTERN SEABOARD TODAY. 
SOME OF THE DETERMINISTIC GUIDANCE HAS THIS MOISTURE/INVERTED TROUGH 
CREEPING NORTHWARD DURING THIS WEEK AND GETTING CLOSE TO NEW ENGLAND 
WED NIGHT INTO THU NIGHT BEFORE THEN GETTING SHUNTED OUT TO SEA FRI. 

OTHERWISE DESPITE AUTUMN ARRIVING LATER TODAY THE SUBTROPICAL RIDGE 
DELIVERS ONE OR MORE DAYS OF ANOMALOUS WARMTH TO THE REGION NEXT 
WEEKEND. THE 12Z ECENS AND 00Z GEFS HAVE 850 TEMPS WARMING TO +14C 
ACROSS SOUTHERN NEW ENGLAND DURING THIS TIME.

     DAILY SENSIBLE WEATHER DETAILS...

TUESDAY NIGHT THRU THU...

DRY AIRMASS OVER NEW ENGLAND ALONG WITH LIGHT WINDS AS SURFACE RIDGE 
AXIS SETTLES ACROSS THE AREA WILL YIELD IDEAL RADIATIONAL COOLING 
CONDITIONS. THIS WILL RESULT IN CHILLY NIGHTS WITH MOST LOCATIONS 
DIPPING INTO THE 40S OUTSIDE THE URBAN AREAS AND AWAY FROM THE 
COASTLINE. HOWEVER AFTERNOON TEMPS WILL RECOVER NICELY TO 65-70. 
GIVEN PROXIMITY OF THE SURFACE HIGH WINDS WILL BE LIGHT WITH LOCAL 
SEABREEZES DEVELOPING DURING THE AFTERNOON. GIVEN THE RADIATIONAL 
COOLING CONDITIONS WILL STRAY AWAY FROM A MODEL BLEND AND FOLLOW THE 
COOLER MOS GUIDANCE AND EVEN SHAVE OFF A FEW MORE DEGS IN THE 
TYPICALLY COOLER LOCATIONS /I.E. NORWOOD-TAUNTON-MARTHAS VINEYARD-
ETC/. AS MENTIONED ABOVE WILL HAVE TO WATCH MOISTURE AND INVERTED 
TROUGH CREEPING UP THE COAST WED NIGHT THRU THU NIGHT. 00Z GEFS HAS 
TRENDED NORTH WITH LOW PROBS OF 0.05 QPF ALONG THE SOUTH COAST. THIS 
SUPPORTS THE FARTHER NORTH SOLUTION OF THE OPERATIONAL 00Z GFS. IN 
ADDITION A MODEL BLEND OF ALL DATASETS BRINGS SLIGHT CHANCE POPS TO 
THE SOUTH COAST WITH A MODEL BLEND OF QPF BRINGING MEASURABLE RAIN 
INTO NORTHERN CT-RI TO SOUTHERN SUBURBS OF BOSTON. 
 

FRI/SAT AND SUN...

SURFACE HIGH SHIFTS WESTWARD FROM OVER NEW ENGLAND TO ACROSS THE 
GREAT LAKES. THIS YIELDS A WARMER WNW LOW LEVEL WIND FLOW INTO NEW 
ENGLAND. THIS SHOULD YIELD TEMPS WELL INTO THE 70S FRI AND THEN 
PUSHING 80 OR SO NEXT WEEKEND. THE RECORDS FOR THE DAY INCLUDE 

     9/27...

BOS...86...1998
BDL...88...1998
PVD...86...1998
ORH...85...1933
 
GIVEN THE TIME RANGE HERE ALONG WITH DEGREE OF UNCERTAINTY WILL 
FOLLOW A MODEL BLEND. HUMIDITY SHOULD BE IN THE COMFORTABLE RANGE 
GIVEN WNW LOW LEVEL LAND TRAJECTORY.

&&

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

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

SHORT TERM /THROUGH TUESDAY NIGHT/...

HIGH CONFIDENCE. VFR. N/NW WIND GUSTS TO 25 KT THIS AFTERNOON...
DIMINISHING TONIGHT. LIGHT WINDS TUE AND TUE NIGHT WITH LOW PROB
OF A SEABREEZE TUE AFTERNOON.

KBOS TERMINAL...HIGH CONFIDENCE. LOW PROB OF A SEABREEZE TUE
AFTERNOON. 

KBDL TERMINAL...HIGH CONFIDENCE.

OUTLOOK...WEDNESDAY THROUGH FRIDAY...

HIGH CONFIDENCE FOR VFR EACH DAY. EXCEPTION WILL BE A LOW RISK OF 
MVFR IN SHOWERS SOUTH COAST INCLUDING THE ISLANDS FROM WED NIGHT 
THRU THU NIGHT.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /THROUGH TUESDAY/...

TODAY AND TONIGHT...MODERATE CONFIDENCE.
SLOWLY BUILDING SWELL MAY APPROACH 10 FT WELL OFFSHORE...BUT
INCREASE TO 5-8FT CLOSER TO THE THE SRN NEW ENGLAND COAST THROUGH
THE DAY...AS W-NW WINDS REACH ABOUT 25 KT. THEREFORE...SMALL CRAFT
ADVISORIES HAVE BEEN ISSUED AND WILL CONTINUE INTO
TONIGHT...DROPPING CLOSE TO SHORE THIS EVENING AS WINDS
DIMINISH. HOWEVER...THE SWELL MAY TAKE UNTIL EARLY TUE MORNING TO
COMPLETELY DIMINISH ON THE S AND SE WATERS.

TUE...HIGH CONFIDENCE.
AFTER THE LEFTOVER SWELL SUBSIDES...A PROLONGED PERIOD OF QUIET
BOATING WEATHER IS EXPECTED AS HIGH PRES BEGINS TO CREST OVER THE
WATERS.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...

HIGH CONFIDENCE...

LIGHT WINDS THRU THE PERIOD AS HIGH PRES REMAINS OVER OR NEAR THE 
REGION. DRY WEATHER AND GOOD VSBY TOO. POSSIBLE EXCEPTION WILL BE 
RAIN SHOWERS WED NIGHT THRU THU NIGHT AS MOISTURE ADVECTS UP THE 
EASTERN SEABOARD.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...HIGH SURF ADVISORY UNTIL 6 PM EDT THIS EVENING FOR MAZ020>024.
NH...NONE.
RI...HIGH SURF ADVISORY UNTIL 6 PM EDT THIS EVENING FOR RIZ006>008.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EDT TUESDAY FOR ANZ231>234.
     SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ230-
     236-251.
     SMALL CRAFT ADVISORY UNTIL 8 AM EDT TUESDAY FOR ANZ235-237.
     SMALL CRAFT ADVISORY UNTIL 11 AM EDT TUESDAY FOR ANZ250-
     254>256.

&&

$$
SYNOPSIS...NOCERA/DOODY
NEAR TERM...KJC
SHORT TERM...DOODY
LONG TERM...NOCERA
AVIATION...KJC/NOCERA
MARINE...NOCERA/DOODY



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