-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBOX 072127
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
427 PM EST FRI MAR 7 2014

.SYNOPSIS...
AN OCEAN STORM WILL LIKELY BRING SOME LIGHT RAIN TO NANTUCKET AND
POSSIBLY AS FAR NORTH AS MARTHAS VINEYARD AND THE OUTER CAPE
TONIGHT. A FEW FLURRIES OR VERY LIGHT SNOW IS ALSO POSSIBLE LATE
SUN NIGHT INTO EARLY MON MORNING WITH A WEAK DISTURBANCE.
OTHERWISE...GENERALLY DRY WITH SEASONABLE TEMPERATURES THROUGH
EARLY NEXT WEEK. A SIGNIFICANT WINTER STORM IS POSSIBLE SOMETIME
WED INTO THU...BUT DETAILS AND PTYPES ARE HIGHLY UNCERTAIN.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
MAIN ISSUE IS HOW FAR NORTH PRECIPITATION GETS THIS EVENING AS OFFSHORE
STORM PASSES BY. AND IF THE PRECIPITATION SHOULD EXTEND TO THE
WEST SIDE OF BUZZARDS BAY AND THE SOUTH COAST OF RI...THERE COULD
BE A PTYPE ISSUE. EXTRAPOLATION OF RADAR TRENDS AND HIGH
RESOLUTION SHORT TERM GUIDANCE...INCLUDING THE HRR...SUGGESTS THAT
MEASURABLE RAIN WILL PROBABLY REACH ACK BUT NOT MUCH FURTHER NORTH
AND WEST OF THERE. THE GFS AND NAM 700 MB HEIGHT HINT AT THE
POSSIBILITY OF A WEAK DEFORMATION ZONE CLOSE TO THE ISLANDS AND
WOULD SEEM TO GIVE A LITTLE MORE CREDENCE TO RAIN AT LEAST
REACHING TO ACK. HAVE GONE WITH LIKELY POPS FOR ACK AND CHANCE AS
FAR NORTH AS A CHH-CUTTYHUNK-BID LINE. COLUMN IS WARM ENOUGH FOR
RAIN ALONG A ACK-MVY-BID LINE. HOWEVER...SHOULD PRECIPITATION
REACH TO THE NEW BEDFORD AND UPPER BUZZARDS BAY AREA...THEN A
WINTRY MIX WOULD BE POSSIBLE. THERE IS A DRY LAYER 5 TO 10K
FEET...SO MAIN THREAT COULD BE A TOUCH OF LIGHT FREEZING DRIZZLE.
THE RISK SEEMS LOW NOW BUT WILL NEED TO BE MONITORED AS EVEN A
VERY LIGHT AMOUNT OF FREEZING DRIZZLE CAN WREAK TRAVEL
HAVOC...PERHAPS ESPECIALLY LATE ON A FRI EVENING.

WENT WITH THE SUPERBLEND FOR TEMPERATURES TONIGHT. LOWEST
CONFIDENCE EXISTS IN RI AND SE MA WHERE TEMPERATURES COULD DROP
CONSIDERABLY LOWER THAN FORECAST IF CLOUDS MOVE OUT FASTER THAN
FORECAST. OVER THE FAR INTERIOR...THERE IS SOME WARMING ALOFT BUT
SHELTERED VALLEYS...ESPECIALLY ACROSS NORTH CENTRAL MA AND SW
NH...MAY DROP INTO THE SINGLE DIGITS UNDER IDEAL RADIATIONAL
COOLING CONDITIONS. MOST OF INTERIOR WILL PROBABLY DROP INTO THE
TEENS TO AROUND 20.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
LOOKS GENERALLY DRY THROUGH THE PERIOD...ALTHOUGH A BAND OF
MOISTURE PASSES ACROSS THE SOUTH COAST AND COULD BE CAPABLE OF A
FEW FLURRIES OR VERY LIGHT SNOW SHOWERS ACROSS THE ISLANDS VERY
EARLY SUN MORNING. HAVE GONE WITH SLIGHT CHANCE POPS ACROSS MVY
AND ACK DURING THE EARLY MORNING HOURS ON SUN WITH NO MENTION OF
PRECIPITATION ANY WHERE ELSE.

HAVE GONE WITH SUPERBLEND GUIDANCE FOR TEMPERATURES SAT AND SAT NIGHT.
COLD AIR ADVECTION DURING THE AFTERNOON MAY CAP OR AT LEAST SLOW
DOWN WHAT MIGHT FIRST APPEAR TO BE A MORE SIGNIFICANT RISE IN
TEMPERATURES DURING THE MORNING AND MIDDAY. LOOKING FOR HIGHS IN
THE LOW TO MID 40S MOST LOCATIONS SAT AFTERNOON WITH UPPER 40S A
POSSIBILITY ACROSS INTERIOR SE MA WHERE LESS SNOWCOVER AND COLD
AIR ADVECTION WILL BE LATER.

LOWERED SUPERBLEND TEMPERATURES A TAD IN THE CT RIVER VALLEY SAT
NIGHT BASED ON MODEL COOLING DEPICTED.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGHLIGHTS...

* DRY AND COLDER ON SUNDAY
* A FEW SNOW SHOWERS POSSIBLE LATE SUN NIGHT/EARLY MON MORNING
* MAINLY DRY AND MILDER BY TUE
* SIGNIFICANT WINTER STORM POSSIBLE WED/THU BUT DETAILS UNCERTAIN

DETAILS...

SUNDAY...

COLDER AIR WILL WORK BACK INTO SOUTHERN NEW ENGLAND AS 850 MB TEMPS
DROP BELOW -10C.  THIS SHOULD KEEP HIGH TEMPS MAINLY IN THE 30S
UNDER BREEZY NORTHWEST WINDS.  DRY WEATHER SHOULD PREVAIL WITH A MIX
OF SUN AND CLOUDS.

SUNDAY NIGHT AND MONDAY...

A MOISTURE STARVED SHORTWAVE WILL DROP DOWN FROM NORTHWEST FLOW
ALOFT.  ENOUGH MID LEVEL MOISTURE AND LIFT MAY BE PRESENT TO
GENERATE A FEW SNOW SHOWERS...MAINLY LATE SUN NIGHT/EARLY MON
MORNING.  ITS POSSIBLE THAT SOME LOCATIONS MAY RECEIVE A VERY SMALL
SNOW ACCUMULATION...WITH THE BEST CHANCE ACROSS THE NORTHERN AND
EASTERN SECTIONS.  HIGHS BY MON AFTERNOON SHOULD RECOVER INTO THE
UPPER 30S AND LOWER 40S.

MONDAY NIGHT AND TUESDAY...

MAY SEE A BRIEF SPOT SNOW SHOWER LATE MON NIGHT NORTH OF THE
PIKE...AS WEAK LOW PRESSURE TRACKS WELL TO OUR NORTH.  OTHERWISE...
A DRY AND PLEASANT DAY APPEARS TO BE IN THE CARDS FOR TUESDAY.
WESTERLY FLOW OUT AHEAD OF THE NEXT COLD FRONT SHOULD ALLOW HIGHS TO
REACH WELL INTO THE 40S...TO PERHAPS NEAR 50 IN SOME LOCATIONS.
PERHAPS EVEN OVER 50 DEGREES IN PORTIONS OF RHODE ISLAND/SOUTHEAST
MA IF THE ECMWF VERIFIES.

WEDNESDAY AND THURSDAY...

THE POTENTIAL FOR A SIGNIFICANT WINTER STORM CONTINUES WED INTO
THU...BUT ITS NOT A CERTAINTY.  KEEP IN MIND THAT THIS POTENTIAL
STORM IS STILL 5 TO 6 DAYS IN THE FUTURE...HENCE MODEL TRACK/PTYPE
AND QPF AMOUNTS ARE QUITE UNCERTAIN.  ENSEMBLE SENSITIVITY PLOTS
SHOW THE MAIN PIECE OF ENERGY THAT CREATES THIS STORM IS STILL WELL
OUT IN THE PACIFIC...WHICH COMBINES WITH NORTHERN STREAM ENERGY
CURRENTLY LOCATED NEAR THE NORTH POLE.  SO AS YOU CAN SEE...THERE
ARE A LOT OF MOVING PARTS TO THIS AND SUBTLE CHANGES IN THE
TIMING/STRENGTH AND INTERACTION BETWEEN THESE WAVES WILL HAVE A HUGE
IMPACT ON THE EVENTUAL OUTCOME.

AS WE TALKED ABOUT YESTERDAY...THERE ARE 3 MAIN POSSIBILITIES THAT
WE WILL DISCUSS.  THE FIRST POSSIBILITY IS THAT THE TIMING/STRENGTH
OF THE ENERGY DOES NOT ALLOW THE TROUGH TO AMPLIFY ENOUGH.  THIS
WOULD RESULT IN A GLANCING BLOW OR MISS FOR MOST OF SOUTHERN NEW
ENGLAND...AS LOW PRESSURE ESCAPES WELL TO OUR SOUTHEAST.  THE SECOND
IS A STORM THAT AT LEAST PARTIALLY PHASES...ALLOWING FOR AN
INTENSIFYING COASTAL STORM TO TRACK NEAR OR INSIDE THE BENCHMARK.
THIS WOULD RESULT IN A SIGNIFICANT SNOWSTORM FOR MUCH OF SOUTHERN
NEW ENGLAND...WITH THE HEAVIEST FALLING ALONG THE COASTAL PLAIN.
THE THIRD IS A HIGHLY AMPLIFIED SOLUTION...WHICH ALLOWS THE LOW TO
HUG THE COAST.  THIS WOULD BRING THE HEAVIEST SNOW TO PORTIONS OF
THE DISTANT INTERIOR...WHILE THE COASTAL PLAIN SEES SNOW CHANGING TO
SLEET AND RAIN.

ALL IN ALL...ITS JUST TOO EARLY TO BITE ON ANY PARTICULAR SOLUTION.
WE WOULD LIKE TO SEE THIS STORM GET INSIDE 96 HOURS TO HAVE MORE
CONFIDENCE IN ANY ONE SOLUTION.  WE CAN SAY THAT THERE REMAINS THE
POTENTIAL FOR A SIGNIFICANT WINTER STORM.  IF THIS DOES COME TO
FRUITION...THERE MAY BE THE NEED FOR WIND ADVISORIES ALONG THE
COAST.  WE ARE FORTUNATE THAT ASTRONOMICAL HIGH TIDES ARE RATHER
LOW OVER THIS TIME.  THE WORST CASE SCENARIO WOULD PROBABLY BE JUST
A ROUND OF MINOR COASTAL FLOODING/SPLASH OVER ALONG THE EASTERN MA
COAST ON THURSDAY.

FRIDAY...

WHAT EVER HAPPENS WITH THIS STORM...APPEARS THAT A SHOT OF COLD AIR
WILL FOLLOW IN ITS WAKE.  HIGHS SHOULD MAINLY BE IN THE 30S TO CLOSE
OUT THE WORK WEEK.

&&

.AVIATION /22Z FRIDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH SATURDAY/...

TONIGHT...MODERATE CONFIDENCE. MOST OF REGION NW OF A FMH-OQU-WST
LINE SHOULD REMAIN VFR TONIGHT...EXCEPT PATCHY MVFR CIGS MAY
PERSIST PORTIONS OF CT RIVER VALLEY. MVFR CIGS LIKELY ALONG AND
SOUTHEAST OF THAT LINE AND AREAS OF IFR CIGS...AND VSBYS 3-5 MI IN
-RA BR MAY OCCUR ACROSS THE ISLANDS 02Z-08Z TIME FRAME.

SAT...HIGH CONFIDENCE OF VFR THROUGHOUT AREA.

SAT NIGHT...HIGH CONFIDENCE OF VFR THROUGHOUT MOST OF AREA. JUST A
LOW CHANCE OF MVFR CIGS ALONG THE SOUTH COAST LATE SAT NIGHT.

KBOS TERMINAL...HIGH CONFIDENCE IN TAF. VFR THRU THE PERIOD.
LIGHT E FLOW BECOMING NNW OVERNIGHT.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF TONIGHT AND HIGH
CONFIDENCE FOR SAT. HAD TO LOWER TO MODERATE CONFIDENCE TONIGHT
DUE TO SC ARND 25 HND FT MOVING BACK OVER FIELD. THINK IT MAY BE
IN/OUT REST OF THIS AFTERNOON AND NOW THINK MAY PERSIST OVERNIGHT.
LACK OF WIND OR OTHER FORCING TO TAKE IT OUT AND NAM BUFKIT
SHOWS MOIST LAYER PERSISTING WELL INTO THE NIGHT BELOW 3K FT. HAVE
HIGH CONFIDENCE...HOWEVER...OF VFR SAT AND SAT NIGHT. LIGHT WINDS.

OUTLOOK...SUNDAY THROUGH WEDNESDAY...

SUNDAY THROUGH TUESDAY...MODERATE TO HIGH CONFIDENCE IN MAINLY VFR
CONDITIONS OVER THIS TIME.  A FEW BRIEF PERIODS OF MVFR CONDITIONS
ARE POSSIBLE WITH THE BEST SHOT LATE SUN NIGHT/EARLY MON IN A FEW
SNOW SHOWERS.

WEDNESDAY...LOW CONFIDENCE.  CONDITIONS MAY DETERIORATE TO IFR
LEVELS SOMETIME WED AFTERNOON OR NIGHT IN SNOW OR MIXED
PRECIPITATION.  STRONG E-NE WINDS MAY DEVELOP IN THE COAST.
-- End Changed Discussion --

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

THROUGH SATURDAY NIGHT...HIGH CONFIDENCE.

AN OCEAN STORM WILL PASS WELL SE OF THE COASTAL WATERS TONIGHT BUT
CAUSE A SWELL TO PROPAGATE INTO THE COASTAL WATERS...FIRST THE S
COASTAL WATERS AND THEN LATER ACROSS THE E COASTAL WATERS. NE
WINDS MAY GUST TO AROUND 20 KT LATE TONIGHT AND EARLY SAT ACROSS
THE FAR S AND SE COASTAL WATERS. HAVE KEPT THE SCA HEADLINES AS
ISSUED WITH THE PRIOR FORECAST.

OUTLOOK...SUNDAY THROUGH WEDNESDAY...

SUNDAY...MODERATE TO HIGH CONFIDENCE.  NORTHWEST WIND GUSTS OF 20 TO
25 KNOTS IN THE COLD AIR ADVECTION PATTERN.  3 TO 6 FOOT SEAS ALSO
EXPECTED ACROSS THE OUTER-WATERS.  SCA HEADLINES WILL LIKELY BE
NEEDED.

SUNDAY NIGHT AND MONDAY...MODERATE TO HIGH CONFIDENCE. WINDS/SEAS
DIMINISH SUN NIGHT AS COLD ADVECTION WEAKENS.  HOWEVER...SHOULD SEE
A ROUND OF SOUTHWEST WIND GUST OF 20 TO 25 KNOTS DEVELOP MON
AFTERNOON.  SEAS WILL ALSO BUILD TO SCA LEVELS ACROSS THE SOUTHERN
ATLANTIC WATERS.

TUESDAY...MODERATE CONFIDENCE.  WINDS/SEAS PROBABLY REMAIN BELOW SCA
THRESHOLDS WITH RELATIVELY WEAK PRESSURE GRADIENT.

WEDNESDAY...LOW CONFIDENCE.  STRONG WINDS AND HIGH SEAS MAY DEVELOP
BY WED NIGHT DEPENDING ON TRACK/INTENSITY OF COASTAL LOW PRESSURE
SYSTEM.  A DECENT SHOT AT LEAST E-NE GALE FORCE WIND GUSTS
DEVELOPING.  EVEN A LOW PROBABILITY OF A BRIEF PERIOD OF STORM FORCE
WIND GUSTS.  SEAS MAY BUILD TO 10 TO 15+ FEET ACROSS THE ATLANTIC
WATERS DEPENDING ON THE TRACK.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...AIR QUALITY ALERT UNTIL 8 AM EST SATURDAY FOR NHZ011.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 10 PM THIS
     EVENING TO 7 PM EST SATURDAY FOR ANZ235-237.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 7 AM TO 7 PM EST
     SATURDAY FOR ANZ250.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 7 PM EST
     SATURDAY FOR ANZ254>256.

&&

$$
SYNOPSIS...FRANK/THOMPSON
NEAR TERM...THOMPSON
SHORT TERM...THOMPSON
LONG TERM...FRANK
AVIATION...FRANK/THOMPSON
MARINE...FRANK/THOMPSON