Area Forecast Discussion
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000
FXUS61 KBOX 100010
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
710 PM EST TUE FEB 9 2016

.SYNOPSIS...
MAINLY DRY CHILLY WEATHER IS IN STORE FOR SOUTHERN NEW ENGLAND
TONIGHT. FAST MOVING LOW PRESSURE MAY BRING SCATTERED LOCALLY HEAVY
SNOW SHOWERS TO THE REGION WEDNESDAY WITH THE HIGHEST RISK ACROSS
NORTHERN CONNECTICUT AND NEAR THE SOUTH COAST. SOME SCATTERED SNOW
SHOWERS ARE LIKELY THURSDAY AND FRIDAY. BITTERLY COLD WEATHER IS
EXPECTED THIS WEEKEND. THERE IS POTENTIAL FOR MORE PRECIP EARLY
NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
645 PM UPDATE..

STILL NOTING SOME PARTLY CLOUDY SKIES ACROSS N CENTRAL AND NE
MA...BUT LOW AND MID LEVEL CLOUDS ARE MOVING QUICKLY NE OVER THE
LAST COUPLE OF HOURS AS SEEN ON IR SATELLITE IMAGERY. ALSO NOTING
A FEW SNOW SHOWERS REACHING FROM THE MID HUDSON VALLEY INTO
PORTIONS OF THE BERKSHIRES AT 23Z. NOT SEEING TOO MUCH EASTWARD
PROGRESS ON NE REGIONAL 88D RADAR...MAINLY DUE TO DRY AIRMASS
ACROSS SOUTHERN NEW ENGLAND. DEWPT DEPRESSIONS ON ORDER OF 7 TO 10
DEGREES IN PORTIONS OF THE CT VALLEY.

NEAR TERM FORECAST LOOKS PRETTY MUCH ON TRACK. HAVE UPDATED TO
BRING CONDITIONS CURRENT.

***SEE TIDES/COASTAL FLOODING SECTION BELOW FOR 7 PM UPDATES***

PREVIOUS DISCUSSION...
OVERNIGHT CLOUDS WILL BE ON THE INCREASE AS SHORT WAVE ENERGY
OVER THE GREAT LAKES AND OH VLY APPROACHES THE REGION. THERE IS
LOW RISK FOR SNOW SHOWERS TO BREAK OUT ACROSS WESTERN CT AND MA
TOWARD DAYBREAK. OTHERWISE FAIRLY TRANQUIL WITH LIGHT WINDS AND
SEASONABLY COOL TEMPS WITH MINS MAINLY IN THE UPPER TEENS AND LOW
20S.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
*** SCATTERED BUT LOCALLY HEAVY SNOW SHOWERS POSSIBLE WITH THE
  HIGHEST RISK ACROSS WESTERN MA/CT AND THE SOUTH COAST ***

WEDNESDAY ...

IMPRESSIVE SHORT WAVE TROUGH MOVES OVER OR JUST OF THE AREA
TOMORROW. THIS FEATURE SHOWS UP NICELY AS A PV ANOMALY ON THE
TROPOPAUSE. MODEST SYNOPTIC SCALE LIFT WITH THIS FEATURE ALONG WITH
DEEP LAYER MOISTURE. THUS THE ENTIRE REGION WILL SEE SCATTERED SNOW
SHOWERS. THE DIFFICULT PART OF THE FORECAST IS THE INTENSITY AND
AREAL COVERAGE OF THIS ACTIVITY AS MESOSCALE ATTRIBUTES COME INTO
PLAY.

GOOD MODEL AGREEMENT THAT THE ATMOSPHERE WILL BECOME QUITE UNSTABLE
WITH BOTH LOW AND MID LEVEL LAPSE RATES GREATER THAN MOIST ADIABATIC
/6.5C-KM/ AND POSSIBLY APPROACHING 8C/KM ALONG WITH TT NEARING 60!
FURTHERMORE THERE APPEARS TO BE SUFFICIENT MOISTURE IN THE COLUMN
FOR THIS INSTABILITY TO BE REALIZED...POTENTIALLY OFFERING A STRONG
RESPONSE IN THE FORM OF SCATTERED HEAVY SNOW SHOWERS.

UNFORTUNATELY MODEL GUID IS NOT IN GOOD AGREEMENT ON SIMULATING
THESE HEAVIER SNOW SHOWERS. THE 12Z GFS IS MOST ROBUST BUT MAY BE
SUFFERING FROM SOME CONVECTIVE FEEDBACK. HOWEVER THE MODEL CONSENSUS
IS THAT THE MOST INTENSE SNOW SHOWERS MAY DEVELOP ACROSS LONG ISLAND
NY AND THEN MOVE ENE OVER BID-MVY AND POSSIBLY ONTO THE SOUTH COAST
OF MA AND RI. THUS GREATEST RISK IS ACROSS THIS REGION ALONG WITH A
POSSIBLE BURST IN THE MORNING OVER WESTERN CT-MA.

WHILE POTENTIAL SNOW TOTALS ARE NOT THAT IMPRESSIVE THE IMPACT WOULD
RESULT FROM A QUICK 1-2" IN A SHORT PERIOD OF TIME. IF THE GFS
SIMULATION IS CORRECT LOCALIZED AMOUNTS OF UP TO 3-4" ARE POSSIBLE.

TIMELINE...SNOW SHOWERS APPROACH WESTERN CT-MA INCLUDING
HARTFORD/SPRINGFIELD AROUND 12Z...THUS POTENTIALLY IMPACTING THE
MORNING COMMUTE. SNOW SHOWERS OVERSPREAD THE REMAINDER OF THE REGION
15Z-18Z AND POSSIBLY LINGERING ACROSS RI/EASTERN MA INCLUDING BOSTON-
PROVIDENCE CORRIDOR TIL 21Z. HENCE POSSIBLY IMPACTING THE LATE DAY
COMMUTE HERE. WILL ISSUE A SPECIAL WEATHER STATEMENT TO HEIGHTEN
PUBLIC AWARENESS ON POTENTIAL IMPACTS AND ALSO ADDRESS THE
UNCERTAINTY.

&&

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

* SNOW SHOWERS POSSIBLE THROUGH SAT
* MUCH COLDER AIR MOVES INTO SOUTHERN NEW ENGLAND FOR THE WEEKEND
* MORE PRECIPITATION POSSIBLE EARLY NEXT WEEK

A COMPLEX FORECAST FOR THE LONG TERM.  THE MODELS ARE IN FAIRLY GOOD
AGREEMENT WITH THE SYNOPTIC SCALE PATTERN WITH CONTINUED TROUGHING
OVER THE EAST COAST AND RIDGING OVER THE WESTERN CONUS.  DIFFERENCES
AND CHALLENGES COME IN THE EXACT PATH OF THE SYNOPTIC FEATURES...
INCLUDING SHORTWAVES...AS WELL AS THE MORE MESOSCALE FEATURES.

WEDNESDAY NIGHT...HIGH CONFIDENCE.
A WEAK SHORTWAVE WILL EXIT SOUTHERN NEW ENGLAND...PUSHING LOW
PRESSURE OUT OF NORTHERN NEW ENGLAND AND INTO THE GULF OF MAINE.
THIS WILL PULL A WEAK COLD FRONT THROUGH THE REGION.  EXPECT THE
OVERNIGHT PERIOD TO BE MOSTLY DRY WITH THE MAIN IMPACT FROM THE
FRONT BEING SOME CLOUDS AND COLDER TEMPERATURES MOVING IN FOR
THURSDAY.

THURSDAY...MODERATE CONFIDENCE.
A STRONGER SHORTWAVE TROUGH MOVES THROUGH SOUTHERN NEW ENGLAND
THURSDAY. BELOW NORMAL TEMPERATURES ARE EXPECTED BEHIND THE COLD
FRONT THAT MOVED THROUGH WEDNESDAY NIGHT.  HOWEVER...THERE IS ENOUGH
LIFT AND MOISTURE ASSOCIATED WITH THE SHORTWAVE THAT WE COULD SEE
SOME SCATTERED SNOW SHOWERS ACROSS THE REGION.  NOT MUCH EXPECTED AT
THIS TIME...PERHAPS AS MUCH AS AN INCH OR TWO IN A FEW SPOTS.

FRIDAY...HIGH CONFIDENCE.
AS AN UPPER LEVEL TROUGH MOVES INTO THE NORTHEASTERN U.S...LOW
PRESSURE IN THE GREAT LAKES MOVES THROUGH NORTHERN NEW ENGLAND
BRINGING AN ARCTIC FRONT THROUGH SOUTHERN NEW ENGLAND. AGAIN...THIS
WILL BRING A CHANCE OF SNOW SHOWERS AHEAD OF THE FRONT. JUST LIGHT
AMOUNTS EXPECTED AT THIS TIME...A DUSTING TO MAYBE AN INCH OR TWO.
THE BIG STORY WITH THIS FRONT WILL BE THE STRONG PUSH OF ARCTIC AIR
MOVING INTO THE REGION. TEMPERATURES FRIDAY WILL ALREADY BE MORE
THAN 10 DEGREES BELOW NORMAL FOR MID FEBRUARY AND THE COLDER AIR IS
YET TO COME.

THIS WEEKEND...HIGH CONFIDENCE.
NOT MUCH...IF ANY...PRECIPITATION IS EXPECTED. INSTEAD THE COLD WILL
TAKE CENTER STAGE...ALONG WITH SOME BITTERLY COLD WIND CHILLS.
ARCTIC AIR CONTINUES TO SEEP INTO SOUTHERN NEW ENGLAND WITH HIGHS
EXPECTED TO BE 20 TO EVEN 25 DEGREES BELOW NORMAL.  WHILE THIS IS
STILL SEVERAL DAYS OUT AND THERE IS SOME UNCERTAINTY TO BE
HAD...09/12Z EPS PROBABILITIES HAVE AN OVER 90 PERCENT CHANCE OF LOW
TEMPERATURES DROPPING BELOW ZERO AND OVER 80 PERCENT CHANCE OF LOW
TEMPERATURES BELOW NEGATIVE 10 DEGREES!  THUS...HAVE HIGH CONFIDENCE
IN BITTER COLD TEMPERATURES THROUGH THE WEEKEND.

IN ADDITION...ON SATURDAY...STRONG LOW PRESSURE IN THE MARITIMES
COUPLED WITH AN EQUALLY STRONG HIGH PRESSURE IN THE GREAT LAKES/OHIO
VALLEY REGION WILL RESULT IN A VERY TIGHT PRESSURE GRADIENT ACROSS
SOUTHERN NEW ENGLAND.  THIS WILL RESULT IN NORTHWESTERLY WINDS
AROUND 20 MPH...GUSTING TO AROUND 30 MPH...EVEN THROUGHOUT MUCH OF
SATURDAY NIGHT.  WITH TEMPERATURES AS COLD AS THEY ARE CURRENTLY
FORECAST TO BE...EVEN JUST SLIGHTLY BREEZY CONDITIONS WILL RESULT IN
VERY COLD WIND CHILLS.  AT THIS TIME...WE ARE LOOKING AT WIND CHILLS
BETWEEN 20 AND 30 DEGREES BELOW ZERO SATURDAY NIGHT.  DURING THE DAY
SATURDAY...WIND CHILLS IN THE SINGLE DIGITS BELOW ZERO AND 5 TO 15
DEGREES BELOW ZERO FOR SUNDAY.  IT WILL DEFINITELY BE A WEEKEND TO
BUNDLE UP AND STAY INDOORS.

MONDAY AND TUESDAY...LOW CONFIDENCE.
THERE ARE SOME INDICATIONS THAT THERE MAY BE A STORM BRINGING SOME
PRECIPITATION TO SOUTHERN NEW ENGLAND EARLY NEXT WEEK.
HOWEVER...WHETHER IT IS RAIN OR SNOW IS UNCERTAIN...AS WELL AS THE
TRACK OF THE POTENTIAL STORM.  STAY TUNED TO FUTURE FORECASTS FOR
MORE INFORMATION.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
FORECASTER CONFIDENCE LEVELS...

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

TONIGHT ... HIGH CONFIDENCE.
MAINLY VFR ACROSS N CENTRAL AND NW MA...OTHERWISE LOW END VFR TO
MVFR CIGS AND VFR VSBYS. REMAINING DRY THROUGH 06Z...THEN CHANCE
FOR SNOW SHOWERS TOWARD DAYBREAK MOVING IN FROM WEST TO EAST.
LIGHT/VRBL OR CALM WINDS.

WEDNESDAY ... LOW TO MODERATE FORECAST CONFIDENCE.
MVFR-VFR LOWERING TO MVFR-IFR FROM WEST TO EAST IN SCATTERED SNOW
SHOWERS. SNOW SHOWERS WILL BE MOST NUMEROUS ALONG THE SOUTH COAST
OF MA AND RI WITH A FEW HEAVY SNOW SHOWERS LIKELY. UNCERTAINTY IS
HOW FAR NORTH DOES HEAVIER ACTIVITY TRACK. CURRENT INDICATES IS
BID-MVY-ACK AND ALONG THE SOUTH COAST OF RI INTO MA. SNOWFALL OF
1-3" IS POSSIBLE IN THIS AREA WITH AN 1" OR LESS ELSEWHERE. THIS
CAN CHANGE SO MONITOR LATER FORECASTS.

KBOS TERMINAL...MAIN CONCERN IS SCATTERED SNOW SHOWERS WED WITH A
FEW LOCALLY HEAVIER SNOW SHOWERS...LIKELY SOUTH OF THE AIRPORT
TOWARD THE SOUTH COAST OF MA.

KBDL TERMINAL...MAIN CONCERN IS SCATTERED SNOW SHOWERS WED AM
WITH A FEW LOCALLY HEAVIER SNOW SHOWERS. EXACT LOCATION DIFFICULT
TO PINPOINT. HOWEVER TIME WINDOW IS 10Z-16Z.

OUTLOOK /WEDNESDAY NIGHT THROUGH SUNDAY/...

WEDNESDAY NIGHT...HIGH CONFIDENCE.  MAINLY VFR CONDITIONS.

THURSDAY THROUGH FRIDAY...MODERATE CONFIDENCE.  MAINLY VFR
CONDITIONS. ARCTIC FRONT MOVES THROUGH THE REGION FRIDAY WITH
GUSTY NW WINDS. CHANCE OF -SHSN. EXPECTED ACCUMULATION LESS THAN
TWO INCHES.

SATURDAY AND SUNDAY...MODERATE CONFIDENCE. MAINLY VFR CONDITIONS.
NW WINDS GUSTING TO 25-30 KTS LIKELY. BITTERLY COLD TEMPERATURES
EXPECTED.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /THROUGH WEDNESDAY/...HIGH CONFIDENCE.

TONIGHT ...

LIGHT WINDS BUT LARGE EASTERLY SWELLS CONTINUE ON THE OCEAN WATERS
OF MA AND RI. OTHER THAN AN ISOLATED SNOW SHOWER MAINLY DRY AND GOOD
VSBY.

WED ...

LOW PRES FORMS OVER SOUTHERN NEW ENGLAND TOMORROW. SCATTERED SNOW
SHOWERS WILL ACCOMPANY THIS BROAD AREA OF LOW PRES. VSBY MAY LOWER
BELOW 1 MILE IN A FEW OF THE HEAVIER SNOW SHOWERS.

OUTLOOK /WEDNESDAY NIGHT THROUGH SUNDAY/...

WEDNESDAY NIGHT...HIGH CONFIDENCE.  SOUTHWESTERLY WINDS SHIFT AROUND
TO THE WEST AS A WEAK COLD FRONT MOVES OVER THE WATERS.  WINDS AND
SEAS DIMINISH SLOWLY BUT WILL REMAIN OVER FIVE FEET.  SMALL CRAFT
ADVISORIES WILL LIKELY BE NEEDED.

THURSDAY...HIGH CONFIDENCE.  WINDS SHIFT TO THE NORTHWEST AND
INCREASE AS THE PRESSURE GRADIENT BETWEEN HIGH PRESSURE IN THE MID-
ATLANTIC AND LOW PRESSURE IN THE MARITIMES INCREASES. SEAS ALSO
INCREASE.  SMALL CRAFT ADVISORIES DEFINITE...LOW PROBABILITY OF GALE
WARNINGS BEING NECESSARY.

FRIDAY...MODERATE CONFIDENCE.  WINDS AND SEAS SUBSIDE AS HIGH
PRESSURE TRIES TO BUILD IN AHEAD OF AN ARCTIC FRONT THAT MOVES
THROUGH FRIDAY NIGHT. SMALL CRAFT ADVISORIES LIKELY.

SATURDAY...MODERATE CONFIDENCE.  NORTHWESTERLY WINDS CONTINUE
BETWEEN LOW PRESSURE IN THE MARITIMES AND HIGH PRESSURE IN THE GREAT
LAKES.  SMALL CRAFT ADVISORIES DEFINITE...WITH A LOW PROBABILITY OF
GALE FORCE WINDS.

SUNDAY...MODERATE CONFIDENCE.  WINDS AND SEAS DIMINISH AS HIGH
PRESSURE BUILDS OVER THE WATERS.  SMALL CRAFT ADVISORIES MAY STILL
BE POSSIBLE.

&&

.TIDES/COASTAL FLOODING...
7 PM UPDATE...STILL SEEING SURGE VALUES BETWEEN 1.5 AND 2 FEET ON
THE RI SOUTH COAST...1 TO 1.5 FEET ON THE MA EAST COAST...AND 3
FEET AT CHATHAM. ALONG MUCH OF THE MA EAST COAST THIS SHOULD NOT
CAUSE ANY PROBLEMS TONIGHT AS THIS HIGH TIDE IS THE LOWER OF THE
TWO HIGH TIDES FOR THE DAY.

ON THE SOUTH COAST OF RI THIS SUSTAINED SURGE WILL LIKELY RESULT
IN SOME SPLASHOVER AND POSSIBLY EVEN SOME MINOR COASTAL
FLOODING...PARTICULARLY WITHIN NARRAGANSETT BAY. THIS WOULD
INCLUDE PROVIDENCE...NEWPORT...AND FALL RIVER. THIS HIGH TIDE
OCCURS AROUND 830 PM THIS EVENING.

FINALLY...TONIGHTS HIGH TIDE AT CHATHAM IS THE HIGHER OF THE TWO
HIGH TIDES FOR TODAY. THIS PLUS THE 3 FOOT SURGE WILL LIKELY
RESULT IN SOME SPLASHOVER AND MINOR COASTAL FLOODING IN CHATHAM...
AND POSSIBLY ALONG OTHER PARTS OF THE EAST COAST OF CAPE COD. HIGH
TIDE HERE WILL OCCUR AROUND 1 AM.

THEREFORE...HAVE ISSUED A COASTAL FLOOD STATEMENT FOR THE RI SOUTH
COAST AND FOR CAPE COD FOR TONIGHT. AGAIN...THE MAIN CONCERNS ARE
WITHIN NARRAGANSETT BAY AROUND 830PM TONIGHT AND AROUND CHATHAM AT
1AM.

ASTRO TIDES REMAIN HIGH TOMORROW WITH MIDDAY HIGH TIDE AT BOSTON
ALMOST 12 FT. HOWEVER WITH LACK OF SURGE AND SEAS CONTINUING TO
ERODE DON/T THINK ANY COASTAL FLOODING WILL MATERIALIZE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST WEDNESDAY FOR ANZ235-237-
     250-254>256.
     SMALL CRAFT ADVISORY UNTIL 7 AM EST WEDNESDAY FOR ANZ251.

&&

$$
SYNOPSIS...NOCERA/RLG
NEAR TERM...NOCERA/RLG/EVT
SHORT TERM...NOCERA
LONG TERM...RLG
AVIATION...NOCERA/RLG/EVT
MARINE...NOCERA/RLG
TIDES/COASTAL FLOODING...NOCERA/RLG


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