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Mesoscale Discussion 999
MD 999 graphic
   
   MESOSCALE DISCUSSION 0999
   NWS STORM PREDICTION CENTER NORMAN OK
   0316 PM CDT SUN MAY 30 2004
   
   AREAS AFFECTED...ERN IA...NRN IL...SRN WI
   
   CONCERNING...TORNADO WATCH 332...
   
   VALID 302016Z - 302215Z
   
   CONTINUE REMAINING VALID PORTION OF WW.  NEW WW WILL BE NEEDED
   ACROSS THE REMAINDER OF NORTHERN ILLINOIS/SOUTHERN WISCONSIN WITHIN
   NEXT HOUR OR TWO.
   
   INCREASING/INTENSIFYING CONVECTION IS ONGOING IN INSTABILITY AXIS
   ALONG/AHEAD OF INITIAL WEAK COLD FRONT ADVANCING INTO THE MID/UPPER
   MISSISSIPPI VALLEY.  MOST INTENSE THUNDERSTORMS REMAIN
   NEAR/SOUTHEAST OF WAVE AT INTERSECTION OF FRONT AND RETREATING
   OUTFLOW BOUNDARY...NOW NORTHEAST OF KEOKUK IA. THIS ACTIVITY IS
   BEING SUPPORTED BY FORCING IN EXIT REGION OF CYCLONIC POLAR JET
   STREAK NOSING INTO THE MISSOURI OZARKS.  ENHANCED LOW-LEVEL
   HODOGRAPHS NEAR UPPER JET AXIS CONTINUE TO SUPPORT POTENTIAL FOR
   STRONG TORNADOES WITH ONGOING SUPERCELLS...IN VERY MOIST BOUNDARY
   LAYER WITH 70F DEW POINTS AND CAPE UP TO 2000 J/KG.
   
   FAVORABLE LARGE-SCALE FORCING FOR UPWARD VERTICAL MOTION MAY SUPPORT
    UPSCALE DEVELOPMENT INTO LARGER MESOSCALE CONVECTIVE SYSTEM
   NORTHEASTWARD ACROSS NORTHERN ILLINOIS THROUGH 31/00Z.
   
   ..KERR.. 05/30/2004
   
   
   ATTN...WFO...LOT...ILX...MKX...LSX...DVN...ARX...
   
   41489128 42059099 42989089 43668982 43248803 42338792
   41798796 40758882 39808988 40129156 
   
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