MESOSCALE DISCUSSION 2563 NWS STORM PREDICTION CENTER NORMAN OK 1201 PM CST WED DEC 22 2004 AREAS AFFECTED...N-CENTRAL/NRN KY...SERN IND...OH EXCEPT FAR NW...NWRN PA...AND FAR WRN NY CONCERNING...PRECIPITATION TRENDS...WINTER PRECIPITATION VALID 221801Z - 222300Z BAND OF HEAVY SNOW...WITH RATES OF 1"/HR LIKELY...WILL TRANSLATE NEWD ALONG AN AXIS FROM SDF TO CMH TO FAR NWRN PA/FAR WRN NY BETWEEN 18-00Z. NARROW TRANSITION ZONE WITH FREEZING RAIN WILL EXIST FROM N-CENTRAL KY NEWD INTO SRN OH...WITH SNOW/FREEZING RAIN TRANSITION ZONE GRADUALLY PROPAGATING SEWD THROUGH THE REMAINDER OF THIS AFTERNOON. AT 1730Z...LEADING SHORTWAVE TROUGH CONTINUES TO TRACK NEWD ACROSS WRN KY ALONG THE STRONG MID-LEVEL BAROCLINIC ZONE LOCATED NEAR THE OHIO RIVER. ELONGATED BAND OF PRECIPITATION...FORCED BY DEEP-LAYER FRONTOGENESIS...EXTENDS FROM NWRN KY TO FAR WRN NY. FORCING WILL BE AUGMENTED BY SHORTWAVE TROUGH/ISENTROPIC ASCENT...WITH 35+ DBZ SNOW LIKELY AT TIMES THIS AFTERNOON ACROSS CENTRAL OH AS SYNOPTIC ASCENT INCREASES FROM THE SW. THIS WILL YIELD NARROW ZONES OF 1"/HR SNOWFALL...LIKELY INVOLVING THE CVG AND CMH METRO AREAS BETWEEN 18-21Z AND MOVING INTO NERN OH NEAR AND SE OF CLE/NWRN PA/FAR WRN NY BETWEEN 20-00Z. DISTINCT BRIGHT BANDING 35 NE HOP TO 15SE SDF SEPARATES SNOW TO THE NORTHWEST FROM NARROW RIBBON /10-20NM WIDE/ OF FREEZING RAIN. LOW-LEVEL COLD ADVECTION AS SURFACE RIDGING BUILDS IN BEHIND FRONTAL SYSTEM SHOULD GRADUALLY ALLOW FOR LOW-LEVEL COOLING AND A SLOW SEWD PROPAGATION OF RAIN/SNOW LINE ACROSS N-CENTRAL KY INTO S-CENTRAL/SRN OH DURING THE NEXT SEVERAL HOURS. ..BANACOS.. 12/22/2004 ...NOTICE... SPC WINTER WEATHER MESOSCALE DISCUSSIONS WILL BE ISSUED ON A SCHEDULED BASIS...FOUR TIMES A DAY...BETWEEN 00-01 UTC... 06-07 UTC...12-13 UTC...AND 18-19 UTC AS SIGNIFICANT SHORT RANGE WINTER WEATHER EVENTS UNFOLD. THIS SCHEDULE WILL BE USED FROM DECEMBER 1 THROUGH FEBRUARY 28. ATTN...WFO...BUF...CTP...PBZ...RLX...CLE...JKL...ILN...LMK...IND... 38708653 39408566 41428213 42997897 43067814 42237885 40838031 39208183 38258391 37168590 36988664 38738653 |