000
ACUS11 KWNS 070041
SWOMCD
SPC MCD 070041
CTZ000-MAZ000-VTZ000-NYZ000-NJZ000-PAZ000-WVZ000-OHZ000-070645-

MESOSCALE DISCUSSION 2069
NWS STORM PREDICTION CENTER NORMAN OK
0641 PM CST FRI DEC 06 2013

AREAS AFFECTED...ERN OH...PA...SRN NY...WRN MA AND CT...NRN NJ

CONCERNING...WINTER MIXED PRECIPITATION

VALID 070041Z - 070645Z

SUMMARY...AREAS OF HEAVY SNOW ARE EXPECTED FROM ERN OH INTO WRN AND
CNTRL PA THIS EVENING...WITH RAIN CHANGING TO SNOW FROM ERN PA INTO
SRN NEW ENGLAND. IN ADDITION...LOCALIZED FREEZING RAIN COULD OCCUR
ACROSS PORTIONS OF S CNTRL PA.

DISCUSSION...SUBSTANTIAL MOISTURE CONTINUES TO LIFT NWD ATOP A COOL
AIR MASS AT THE SURFACE AND IN ASSOCIATION WITH STRONG
FRONTOGENETICAL FORCING AS THE UPPER TROUGH NEARS.

SURFACE ANALYSIS SHOWS TEMPERATURES ONLY MARGINALLY BELOW FREEZING
OVER MUCH OF THE AREA...WITH WARMER PROFILES/RAIN FROM SERN PA INTO
NEW ENGLAND. MEANWHILE...TEMPERATURES WERE FIRMLY SUPPORTING SNOW
OVER OH AND INTO WRN PA. UPSTREAM HRLY QPF CURRENTLY SUGGESTS
SNOWFALL RATES AROUND 0.50 IN/HR. HOWEVER...HEAVIER PRECIPITATION
WAS OCCURRING IN LIQUID FORM NEAR THE ZONE OF 850 MB WARM ADVECTION
WITH HRLY RATES UP TO 0.25 INCHES.

WITH TIME...AS THE COLUMN COOLS...THE RAIN/SNOW LINE WILL ADVANCE
SEWD. THIS WILL ALSO TEND TO VEER 850 MB WINDS...WITH LESS QPF IN
THE COLDER AIR WITH TIME AND EWD EXTENT.  THEREFORE...IT APPEARS THE
BEST SHOT AT HEAVY SNOW WILL BE ACROSS WRN AND CNTRL PA THIS
EVENING.

..JEWELL.. 12/07/2013

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

ATTN...WFO...BOX...OKX...ALY...PHI...BGM...BUF...CTP...PBZ...
CLE...

LAT...LON   42837460 42867334 42587259 42317230 42067237 41787270
            41457341 40857519 40197791 39767981 39798105 40378122
            40898061 42097760 42837460