ZCZC SPCSWOMCD ALL
ACUS11 KWNS 222347 
SPC MCD 222347 
WVZ000-VAZ000-MDZ000-230445-

MESOSCALE DISCUSSION 0055
NWS STORM PREDICTION CENTER NORMAN OK
0547 PM CST FRI JAN 22 2016

AREAS AFFECTED...PORTIONS OF WV...WRN VA...WRN MD

CONCERNING...HEAVY SNOW 

VALID 222347Z - 230445Z

SUMMARY...A BAND OF HEAVY SNOW WILL DEVELOP NORTHWARD ACROSS WESTERN
VA INTO EASTERN WV AND WESTERN MD OVER THE NEXT FEW HOURS. SNOWFALL
RATES OF 1-2 INCHES PER HR /WITH LOCALIZED RATES UPWARDS OF 2-3
INCHES PER HR/ WILL BE POSSIBLE.

DISCUSSION...WATER-VAPOR IMAGERY AND THE REGIONAL RADAR MOSAIC
SUGGEST A BAND OF HEAVY SNOW IS BLOSSOMING ACROSS THE MCD AREA IN
RESPONSE TO INCREASING LARGE-SCALE ASCENT...AS AN IMPULSE OVER THE
SRN APPALACHIANS CONTINUES TO ROTATE AROUND THE PERIPHERY OF THE
MATURING UPPER TROUGH. STRENGTHENING WAA AT LOW/MID LEVELS...IN
COMBINATION WITH ENHANCED FRONTOGENETIC CIRCULATIONS...WILL FAVOR A
BAND OF HEAVY SNOWFALL RATES THIS EVENING. ADDITIONALLY...LAST
VISIBLE IMAGES PRIOR TO NIGHTFALL INDICATED SMALL CONVECTIVE
ELEMENTS WITHIN THIS GROWING SNOW BAND...FAVORING ENHANCED RATES.
DUAL-POL ZDR AND KDP DATA FROM KFCX CONFIRM THAT DEEPER/STRONGER
CRYSTAL GENERATION ALOFT IS OVERSPREADING THE REGION...IN RESPONSE
TO INCREASING ASCENT WITHIN THE -10 TO -20 C LAYER. KRLX ALSO
DEPICTS SUCH SIGNATURES TO ITS EAST AND NORTHEAST. EFFICIENT CRYSTAL
GENERATION AND THEN AGGREGATION BENEATH THAT LAYER WILL FAVOR VERY
HEAVY SNOW AT TIMES...WITH LOCALIZED RATES UPWARDS OF 3 INCHES PER
HOUR AND LOW VISIBILITIES THIS EVENING.

..PICCA.. 01/22/2016

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

ATTN...WFO...LWX...RNK...PBZ...RLX...

LAT...LON   37258092 38508060 39248030 39587965 39587806 39197796
            38407873 37147914 36707970 36728037 36828073 37258092 

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