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000
ACUS11 KWNS 270928
SWOMCD
SPC MCD 270928
MEZ000-MAZ000-NHZ000-RIZ000-CTZ000-NYZ000-VTZ000-271430-

MESOSCALE DISCUSSION 0045
NWS STORM PREDICTION CENTER NORMAN OK
0328 AM CST TUE JAN 27 2015

AREAS AFFECTED...SERN NY...CT...RI...MA...SRN NH AND SERN ME

CONCERNING...BLIZZARD

VALID 270928Z - 271430Z

SUMMARY...HEAVIEST SNOW BANDS WITH OCCASIONAL RATES OF 2+ INCHES PER
HOUR WILL PERSIST THROUGH THE EARLY MORNING FROM ERN LONG ISLAND NWD
THROUGH ERN CT...RI INTO PARTS OF CNTRL AND ERN MA. FARTHER NORTH
SNOW WILL GRADUALLY INCREASE WITH OCCASIONAL 2+ INCHES PER HOUR
RATES FROM SRN NH THROUGH ERN MAINE THROUGH 15Z. IMMEDIATELY
SURROUNDING THE HEAVIEST BANDS...SNOWFALL RATES UP TO 1 INCH PER
HOUR AT TIMES WILL PERSIST NEXT SEVERAL HOURS.

DISCUSSION...AS OF 09Z THE HEAVIEST SNOW BANDS WITH RATES OF 2+
INCHES PER HOUR HAVE REORGANIZED FROM ERN LONG ISLAND NWD THROUGH
ERN CT...RI INTO CNTRL/ERN MA AND SERN NH. THIS BAND OF SNOW IS
ASSOCIATED WITH A ZONE OF LOW-MID LEVEL FRONTOGENETIC FORCING AND
DEEP-LAYER ASCENT ALONG A N-S ORIENTED DEFORMATION AXIS. WV IMAGERY
AND RAP ANALYSIS SHOW A COMPACT VORTICITY MAXIMUM JUST SOUTH OF LONG
ISLAND SITUATED WITHIN THE LEFT EXIT REGION OF A STRONG UPPER JET
OVER THE WRN ATLANTIC. AS THESE FEATURES CONTINUE NWD...ZONE OF
STRONGEST ASCENT WILL GRADUALLY DEVELOP THROUGH SERN NEW ENGLAND
INCLUDING SERN MAINE THROUGH THE EARLY MORNING. IN ADDITION TO HEAVY
SNOW...THE NELY LLJ IS EXPECTED TO INCREASE TO 70+ KT OVER SERN NEW
ENGLAND WITHIN GRADIENT ZONE BETWEEN THE NWD-MOVING OFFSHORE SFC LOW
AND HIGH PRESSURE OVER SERN CANADA. SFC WINDS WILL CONTINUE TO GUST
IN EXCESS OF 50 KT IN THIS REGION.

AREA OF HIGHER REFLECTIVITY NEAR NANTUCKET APPEARS TO INDICATE A
HEAVY WET SNOW AS A WARM NOSE ALOFT ADVECTS WWD ALONG THE INTENSE
LLJ. SOME OF THIS SNOW MIGHT OCCASIONALLY MIX WITH SLEET FROM
NANTUCKET ISLAND AND POSSIBLY NWD TO ERN CAPE COD...BUT THE
PREDOMINANT PRECIPITATION TYPE WILL PROBABLY REMAIN SNOW.

WEST OF THE HEAVY SNOW BAND FROM NRN NJ THROUGH NEW YORK CITY INTO
WRN CT AND WRN MA...SNOWFALL RATES ARE EXPECTED TO REMAIN GENERALLY
LESS THAN 1 INCH PER HOUR.

..DIAL.. 01/27/2015

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...CAR...GYX...BOX...OKX...ALY...

LAT...LON   40697362 42287293 44537053 45466813 45106726 44526732
            43306992 41687012 40367216 40697362