000
ACUS11 KWNS 040001
SWOMCD
SPC MCD 040001
MAZ000-RIZ000-NHZ000-CTZ000-NYZ000-VTZ000-NJZ000-PAZ000-040400-

MESOSCALE DISCUSSION 0111
NWS STORM PREDICTION CENTER NORMAN OK
0601 PM CST TUE MAR 03 2015

AREAS AFFECTED...PORTIONS OF CNTRL/ERN PA...NJ...SERN NY INTO SRN
NEW ENGLAND

CONCERNING...WINTER MIXED PRECIPITATION

VALID 040001Z - 040400Z

SUMMARY...AREAS OF SLEET AND FREEZING RAIN ARE ONGOING FROM PORTIONS
OF CNTRL/ERN PA AND NJ INTO SERN NEW YORK...AND WILL SPREAD ENEWD
DURING THE NEXT FEW HOURS...WITH WINTER MIXED PRECIP REMAINING
POSSIBLE ACROSS THE DISCUSSION AREA THROUGHOUT THE EVENING.

DISCUSSION...A PLAN-VIEW DEPICTION OF 1.5-KM-AGL FLOW SAMPLED BY
REGIONAL VWPS HIGHLIGHTS THE EXTENSIVE LLJ STRETCHING FROM THE OHIO
VALLEY ENEWD INTO PA AND SRN NY. ENHANCED LOW-LEVEL ASCENT WITHIN
THE BROADER TERMINUS OF THE LLJ IS SUPPORTING A SHIELD OF
PRECIPITATION FROM NY INTO ERN PA AND NJ...SPREADING ACROSS SRN NEW
ENGLAND. ISENTROPIC ASCENT ALONG THE LLJ IS MAINTAINING
PRECIPITATION WELL WSWWD INTO THE OHIO VALLEY THAT WILL SPREAD
ACROSS THE DISCUSSION AREA THIS EVENING.

SFC TEMPERATURES REMAIN BELOW FREEZING ACROSS THE AREA...WITH
NOCTURNAL COOLING BEGINNING TO OFFSET WAA-INDUCED SFC WARMING
ACCOMPANYING THE SLY SFC-FLOW COMPONENT. AS SUCH...A MIX OF WINTER
PRECIPITATION TYPES WILL PERSIST INTO THE EVENING...WITH INITIALLY
SNOW ACROSS PARTS OF SERN NY AND SRN NEW ENGLAND BECOMING REPLACED
BY THE WINTRY MIX. WITH EXPECTED WARMING ALOFT OWING TO
WAA...PARTIAL TO PERHAPS NEARLY COMPLETE MELTING OF HYDROMETEORS
WILL OCCUR. FREEZING RAIN RATES OF 0.02 TO PERHAPS LOCALLY 0.05 INCH
PER HOUR -- MAINLY ACROSS PARTS OF PA INTO NJ -- WILL BE POSSIBLE.
HOWEVER...SLEET IS EXPECTED TO CONTINUE BECOMING PREDOMINANT...WITH
SLEET ACCUMULATION RATES AROUND 0.05-0.15 INCH PER HOUR.

SIMILAR WINTER MIXED PRECIPITATION IS FORECAST TO PERSIST THROUGH
THE EVENING. A TENDENCY FOR WEAKENING ASCENT/DRYING ALOFT IS
EXPECTED TO RESULT IN DECREASING PRECIPITATION COVERAGE/INTENSITY IN
THE 03Z-06Z TIME FRAME...FROM WSW TO ENE.

..COHEN.. 03/04/2015

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

ATTN...WFO...BOX...OKX...ALY...PHI...BGM...CTP...

LAT...LON   40207453 39777662 40087783 40847785 42247540 42937243
            42567090 41747060 40887269 40207453