000
FXUS61 KBOX 240926
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
426 AM EST TUE NOV 24 2009

.SYNOPSIS...
LOW PRESSURE WILL PASS WELL EAST OF NANTUCKET THIS AFTERNOON AND EVENING.
WEAK HIGH PRESSURE WILL MOVE ACROSS NEW ENGLAND WEDNESDAY. A LARGE GALE
SHOULD BE CENTERED NEAR THE NEW ENGLAND COAST FRIDAY...THEN SPIN AWAY
INTO THE MARITIMES THIS WEEKEND. ANOTHER AREA OF LOW PRESSURE IS EXPECTED
TO DEVELOP OVER THE NE USA EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
RADAR STP IS MUCH TOO HIGH BUZZARDS BAY SOUTHWARD...OTRW OK IN SNE. 

LEFTOVER LIGHT LOW TOP R/DRIZZLE IS EXPECTED THIS MORNING INTO THE
EARLY AFTN...SHRINKING FROM ITS 3AM COVERAGE TO MOSTLY E MASS BY
FORENOON.  

TEMPS ARE THE COLDER NAM/UK/RGEM IDEA VS THE MILDER LESS RESOLVED GFS.

SUSTAINED WINDS WERE A 60/40 BLEND OF 00Z/24 NAM/GFS MOS WINDS.
GUSTS WERE DERIVED FROM THE 00Z/24 BUFKIT. GFS GUSTS FOR 06Z
VERIFIED AS BETTER PREDICTOR INITIALLY.

CLOUD COVER FAVORED THE MORE ROBUST BL RH OF THE NAM WITH RGEM
SKYCOVER SUPPORT. 06Z NAM CONTS TO SUPPORT. LOTS OF LINGERING NE TOP
OF THE BL FLOW.

POPS FCST WAS THE 21Z SREF SUPPORTED BY ITS 03Z/24 VSN AND ALSO THE
RGEM/GGEM/UK SPITTING OUT MEAGER AMTS OF NUISANCE R/DRIZZLE-GENERALLY
UNDER .10 INCHES AFTER 09Z TODAY....NOT THE SOMEWHAT HEAVIER SHOWERS
OF THE PAST 12 HOURS WHEN WIDESPREAD .25 TO .75 INCHES OCCURRED S OF THE
MA PIKE. 

SURGE GUIDANCE IS MISSING THE HALF A FOOT DEPARTURE AT 3AM BOS/ACK/PVD.
THE TWL PRODUCT WAS UPDATED WITH A NEW STORM TIDE SUM BASED ON SURGE
ADJUSTMENTS THRU ABOUT 20Z TODAY.

CONFIDENCE IS AVG OR ABV AVG.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
COULD NOT BUY INTO THE DRYING OF THE 00Z/24 GFS. SREF POPS AND COMBINED
NAM/RGEM/GGEM/UKMET CUES SUGGEST THAT ANY CLEARING IF IT OCCURS THIS
EVENING WOULD PERMIT QUICK RADIATION FOG/ST FORMING. SO THE FCST
DECISION WAS TO STAY MORE MOIST THAN THE GFS. THAT NARROWS THE
FORECAST DIURNAL TEMPS...INCREASES SFC TDS AND MEANS MORE CLOUDS AND
POSSIBLY EVEN A COUPLE OF POCKETS OF T TO .01 R-/L-.

BASICALLY NOT A LOT OF CLEARING FCST...THO ITS POSSIBLE THAT THERE
WILL BE MORE THAN INDICATED WITHIN THE NEW UPCOMING 4 AM FCST.

CONFIDENCE ON DETAILS AND DEPARTURE FROM MOS IS AVG.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
DYNAMIC UPPER TROF AND POSSIBLE VIGOROUS AND INTENSIFYING COASTAL 
SURFACE LOW PRES FRI...FOLLOWED BY A BLUSTERY SAT.

LIGHT ONSHORE FLOW AND PROBABLE INVERSION ON THANKSGIVING DAY 
SUGGEST CONSIDERABLE LOW CLOUDINESS WITH HIGH CLOUDS ASSOCIATED WITH 
LARGE AMPLITUDE SHORT WAVE TROF INCREASING ALOFT DURING THE 
AFTERNOON. HAVE KEPT POPS IN SLIGHT CHANCE RANGE FOR MOST OF THE 
DAY...INCREASING TO CHANCE WEST DURING THE LATE AFTERNOON.

THU NIGHT AND FRI BECOME MORE INTERESTING. CONSENSUS OF ALL MEDIUM 
RANGE MODELS SHOWS DEEPENING 500 MB CLOSED LOW PASSING IN THE 
VICINITY OF SOUTHERN NEW ENGLAND. ALL MODELS ALSO INDICATE 
INTERACTION WITH SOUTHERN STREAM WITH DEEPENING SURFACE LOW PRES 
BEING A PRODUCT OF THE NORTHERN STREAM STRONG SHORT WAVE TROF 
PHASING WITH THE SOUTHERN STREAM ENERGY. AS IS USUALLY THE 
CASE...THE TIMING OF THE PHASING CAN HAVE CONSIDERABLE IMPACT ON THE 
FORECAST. GEM IS THE LEAST IMPRESSIVE BUT STILL FORMS A 
CLOSED...ALBEIT PROGRESSIVE...UPPER LOW OVER SOUTHERN NEW ENGLAND 
LATE FRI. THE GFS AND UKMET ARE MOST ROBUST WITH A DEEPER AND 
FURTHER SOUTH UPPER LOW AND MORE INTENSE SURFACE CYCLOGENESIS. THE 
ECMWF IS SOMEWHAT IN BETWEEN AND SEEMS TO BE REASONABLY IN CONCERT 
WITH GFS ENSEMBLE MEMBERS. FORECAST REPRESENTS A BLEND OF THE ECMWF 
AND GFS...BUT WEIGHTED MORE TOWARD THE GFS. WITH ALL THAT 
STATED...HAVE GONE HIGH LIKELY TO LOW CAT POPS FOR LATE THU NIGHT 
AND FRI. BELIEVE BEST CHANCE FOR POPS WILL BE NORTHERN ZONES AND 
THAT FITS WITH GYX THINKING. TOTAL TOTALS ARE HIGH ON THE GFS FRI 
AFTERNOON AND EVENING...PEAKING AROUND 56. CAN NOT RULE OUT ISOLATED 
THUNDER...ESPECIALLY IF UPPER LOW CENTER DOES INDEED DEEPEN AS IT 
TRACK ACROSS REGION. QPF AMOUNTS MAY BE VARIABLE GIVEN WHAT 
ANTICIPATE TO BE SHOWERY NATURE TO PRECIPITATION.

PTYPE IS NOT  AN ISSUE UNTIL FRI NIGHT/EARLY SAT MORNING WHEN 
DROPPING TEMPERATURES/THICKNESSES SUPPORT POSSIBILITY OF WET SNOW 
MIXED WITH THE RAIN OVER THE HIGH TERRAIN OF NW MA AND SW NH. NO 
SIGNIFICANT ACCUMULATION IS EXPECTED AT THIS TIME.

WITH HIGH CONFIDENCE...EXPECT SAT TO BE BLUSTERY AND SHOULD FEEL 
NOTICABLY COLDER THAN OTHER DAYS THIS MONTH. NW WIND GUSTS MAY 
SUPPORT WIND ADVISORY ISSUANCES IN A FEW LOCATIONS ALONG WITH A GALE 
OVER THE COASTAL WATERS. MAY BE A LITTLE TOO HIGH WITH MAX 
TEMPERATURES IN MID/UPPER 40S ON SAT FOR MOST LOCATIONS.

IN RESPONSE TO LARGE SCALE LONG WAVE PATTERN AND BUILDING 
HEIGHTS...AIR MASS BEGINS TO RECOVER FAIRLY QUICKLY ON SUN BUT A 
CHILLY START AND SHORT DAYLIGHT MAY DAMPEN RECOVERY OF SURFACE 
TEMPERATURES. CONCERNED THOUGH THAT PREDICTED MAX TEMPERATURES MAY 
BE TOO COOL FOR SUN.

NEXT POTENTIAL PRECIPITATION SYSTEM LOOKS TO APPROACH FROM THE OH 
VALLEY MON NIGHT OR TUE. HAVE KEPT POPS IN SLIGHT CHANCE CAT FOR 
MON. THIS IS RATHER FAR OUT AND THE ECMWF SHOWS A MUCH LESS 
AMPLIFIED SYSTEM THAN THE GFS DOES WITH THE LEAD SHORT WAVE TROF. 


&&

.AVIATION /09Z TUESDAY THROUGH SATURDAY/...
TODAY...IFR CIGS. VSBY OCCASIONALLY 2-5 MI THIS MORNING IN R/DRIZZLE
EXCEPT OCCASIONALLY 1/4SM IN FOG KORH EARLY THIS MORNING. VSBY SHOULD
IMPROVE TO 6+ THIS AFTN AS CIGS RISE 200 FT FROM CURRENT 08Z OBS. 

NE GUSTS 15-20 KTS ALL MASS RI N CT TAF SITES TODAY EXCEPT 25-35KT 
HYA FMH AND ACK THRU 20Z TODAY.

PLS SEE TAFS FOR DETAILS.

TONIGHT...MVFR OR IFR CIGS. IF IT CLEARS INTERIOR THEN LIFR ST/FOG
WOULD BE DEVELOPING CT RVR VALLEY. WINDS DIMINISH AND TURN MORE
NORTHERLY ALONG THE COAST....GUSTS 20-25 KTS STILL POSSIBLE KACK AND
KHYA EARLY.  

WED...LOOKS LIKE MVFR OR POSSIBLY EVEN IFR CIGS MUCH OF THE DAY...ESP
COAST. BAF/BDL MIGHT IMPROVE TO VFR CIGS MIDDAY. 

OUTLOOK /THURSDAY THROUGH SATURDAY/... 
THU...MVFR CIGS. 
THU NIGHT AND FRI...BECOMING WIDESPREAD MVFR CIGS AND VSBYS WITH
AREAS OF IFR CONDITIONS. IMPROVING TO VFR BY SAT MORNING.
SAT...VFR BUT STRONG SURFACE WINDS G25 TO PERHAPS 30 KT AND
ASSOCIATED MECHANICAL TURBULENCE.

&&

.MARINE...
TRIMMED THE GALE TO NR AND SE OF KACK BASED ON 00Z/24 GFS BUFKIT
OUTPUT. SCA EXTENDED THROUGH MIDDAY WED OUTER WATERS. 

NE SCA TODAY WITH SPOTTY GALE NR AND SE OF KACK THIS MORNING. 
10 TO 13 FT OPEN WATERS SEAS E OF MASSACHUSETTS WILL BE SLOW TO
SUBSIDE WED.  


OUTLOOK /WEDNESDAY THROUGH SATURDAY/...

ROUGH SEAS EXPECTED TO LINGER ACROSS THE OUTER COASTAL WATERS OF MA
AND RI WEDNESDAY NIGHT THROUGH THURSDAY. OTHERWISE...RELATIVE LIGHT ONSHORE
FLOW THU...INCREASING FROM NE LATE THU NIGHT AND FRI. HOW STRONG THE
NE WINDS WILL BE DEPENDS UPON SURFACE LOW TRACK AND INTENSITY...AND
THERE IS CONSIDERABLE UNCERTAINTY ON THAT NOW. THERE IS RELATIVELY
HIGH CONFIDENCE...HOWEVER...OF A NW GALE DEVELOPING LATE FRI NIGHT
AND SAT ACROSS MOST OF THE COASTAL WATERS BEHIND DEEPENING SURFACE
LOW IN THE GULF OF ME. NOT OUT OF THE QUESTION THAT THE SYSTEM COULD
PRODUCE STORM FORCE GUSTS ON THE BACKSIDE AS IT DEEPENS OVER THE GULF
OF ME AND MARITIMES. THE WNA GUIDANCE LOOKED REASONABLE AND HAVE NOT
STRAYED FROM IT FOR THIS FORECAST ISSUANCE.

PERSISTENT ONSHORE FLOW AND LARGE EASTERLY OCEAN SWELLS OF 6 TO 10
FEET MOST OF THIS WEEK COULD LEAD TO SIGNIFICANT BEACH EROSION. WE
COULD SEE A SURGE OF 1.0 TO 1.5 FT BUT ASTRONOMICAL TIDES ARE QUITE LOW.

&&

.EQUIPMENT...
TDWR TBOS CONT OTS. 
44020 ACK SOUND BUOY CONT OTS. NDBC MAINTENANCE HAS STATUS.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...GALE WARNING UNTIL 2 PM EST THIS AFTERNOON FOR ANZ232-254-255.
     SMALL CRAFT ADVISORY UNTIL 5 AM EST WEDNESDAY FOR ANZ231-
     233>235-237.
     SMALL CRAFT ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR ANZ230-
     236.
     SMALL CRAFT ADVISORY UNTIL NOON EST WEDNESDAY FOR ANZ250-251-
     256.

&&

$$
SYNOPSIS...DRAG/THOMPSON
NEAR TERM...DRAG
SHORT TERM...DRAG
LONG TERM...THOMPSON
AVIATION...DRAG/THOMPSON
MARINE...DRAG/THOMPSON
EQUIPMENT...DRAG