MESOSCALE DISCUSSION 2511
   NWS STORM PREDICTION CENTER NORMAN OK
   0622 PM CST TUE DEC 23 2008
   
   AREAS AFFECTED...ECNTRL/NERN IL...NRN IND...SRN MI...NWRN OH
   
   CONCERNING...WINTER MIXED PRECIPITATION 
   
   VALID 240022Z - 240415Z
   
   CORRECTED FOR SURFACE ID...CHANGED ADH TO AOH
   
   A PERIOD OF FREEZING RAIN IS EXPECTED THIS EVENING WITH ACCUMULATING
   RATES AOA 0.05 TO 0.10" PER HOUR.
   
   A BROAD PRECIPITATION SHIELD CONTINUES TO LIFT NEWD AS STRONG SWLY
   FLOW/ISENTROPIC UP GLIDE CONTINUE OVER THE AREA. GIVEN THE STRONG
   LOW LEVEL JET AND ASSOCIATED WARM ADVECTION...MODERATE TO STRONG
   ASCENT WILL CONTINUE FROM THE LOWER MS VALLEY TO THE GREAT LAKES. 
   THE PRECIPITATION TYPE WILL GRADUALLY CHANGEOVER FROM FREEZING RAIN
   TO RAIN IN THE SOUTH...AND SNOW TO FREEZING RAIN IN THE NORTH.
   PRECIPITATION RATES WILL CONTINUE AT OR ABOVE 0.05-0.10" THIS
   EVENING...PARTICULARLY WITHIN A ZONE OF ENHANCED ASCENT/SLANTWISE
   CONVECTION EVIDENT ON RADAR BETWEEN FROM CMI TO AOH AND PREDICTED TO
   SHIFT EWD/NEWD THIS EVENING PER THE 18 UTC SREF AND 22 UTC RUC. DUE
   TO THE VERY COLD GROUND TEMPERATURES FOLLOWING THE RECENT ARCTIC
   AIRMASS...FREEZING RAIN MAY LINGER EVEN AS SURFACE AIR TEMPERATURES
   RISE SLIGHTLY ABOVE FREEZING.
   
   ..BRIGHT.. 12/24/2008
   
   
   ...NOTICE...
   SPC WINTER WEATHER MESOSCALE DISCUSSIONS WILL BE ISSUED ON A
   SCHEDULED BASIS FROM DECEMBER 1 THROUGH FEBRUARY 28...FOUR
   TIMES A DAY...AROUND 00 UTC...06 UTC...12 UTC...AND 18 UTC
   FOR SIGNIFICANT SHORT RANGE WINTER WEATHER EVENTS.
   
   ATTN...WFO...CLE...ILN...DTX...IWX...GRR...IND...LOT...ILX...
   
   LAT...LON   41768759 42218627 42538514 42708419 42698371 42618275
               42358239 41818232 41378253 41128276 40978330 40678396
               40528457 40308518 40068606 39908674 39768745 39718825
               39718891 39878950 40589009 41498839 41768759