MESOSCALE DISCUSSION 2552
   NWS STORM PREDICTION CENTER NORMAN OK
   0659 PM CST MON DEC 20 2004
   
   AREAS AFFECTED...EXTREME NE IA/SW WI INTO UPPER MI/NRN LOWER MI
   
   CONCERNING...HEAVY SNOW 
   
   VALID 210059Z - 210500Z
   
   MODERATE TO OCCASIONALLY HEAVY SNOW IS EXPECTED TONIGHT FROM SWRN WI
   INTO UPPER MI. AS WINDS BECOME WLY OFF LAKE MI...SNOW BANDS WILL
   DEVELOP AND MOVE ONSHORE FROM LAKE ENHANCEMENT.
   
   LATEST WATER VAPOR IMAGERY SHOWS UPPER CIRCULATION IS PASSING OVER
   CNTRL ND...WITH SHARPLY DEFINED JET STREAK EXTENDING FROM THE CNTRL
   PLAINS INTO ERN IA/NRN IL. SFC COLD FRONT EXTENDS FROM AROUND GRAND
   FORKS TO JUST NORTHWEST OF PIERRE. FRONT...AND ASSOCIATED ARCTIC
   AIRMASS...WILL RACE SEWD WITH 2-3MB/HR PRESSURE RISES AND SUSTAINED
   SFC WINDS FROM 30-40 MPH WITH GUSTS ABOVE 60 MPH. LATEST RADAR
   IMAGERY FROM LA CROSSE WI SHOWS MAIN SNOW BAND WILL PROVIDE A SHORT
   BURST OF HEAVY SNOW...GENERALLY FROM VOK/GRB...AND THEN SNOW RATES
   WILL TAPER OFF LATER THIS EVENING.
   
   FARTHER NORTHEAST IN UPPER MI...SEVERE WINTER WEATHER WILL CONTINUE
   WITH MOD/HEAVY SNOW RATES OF 1-2"/HR...COMBINED WITH GUSTY SFC WINDS
   MAKING FOR NEAR BLIZZARD CONDITIONS GIVEN ABUNDANT SNOW ALREADY ON
   THE GROUND. RADAR IMAGERY FROM GREEN BAY INDICATES A LAKE EFFECT
   SNOW BAND FROM JUST WEST OF MANISTEE TO ERN LAKE SUPERIOR. AS WINDS
   VEER IN RESPONSE TO APPROACHING SFC BOUNDARY...THIS BAND WILL SHIFT
   EWD FURTHER ENHANCING HEAVY SNOW RATES.
   
   ..TAYLOR.. 12/21/2004
   
   
   ...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...APX...GRR...MQT...GRB...MKX...DVN...ARX...
   
   44098489 43998628 44208720 43798813 43518903 42639114
   43009156 43759144 44839027 46468619 46798520 46238365
   45018338