MESOSCALE DISCUSSION 1664
   NWS STORM PREDICTION CENTER NORMAN OK
   0720 PM CDT FRI JUL 24 2009
   
   AREAS AFFECTED...EASTERN IA/NORTHERN IL/FAR SOUTHWEST WI
   
   CONCERNING...TORNADO WATCH 619...
   
   VALID 250020Z - 250145Z
   
   THE SEVERE WEATHER THREAT FOR TORNADO WATCH 619 CONTINUES.
   
   TORNADO WATCH 619 CONTINUES UNTIL 04Z ACROSS EASTERN IA/NORTHWEST IL
   AND ADJACENT FAR SOUTHWEST WI...WITH CONTINUED POTENTIAL FOR LARGE
   HAIL/DAMAGING WINDS AND A TORNADO.
   
   CENTERED ALONG THE MS RIVER...SCATTERED/MODESTLY DISCRETE SUPERCELLS
   CONTINUE TO SPREAD SOUTHEASTWARD OVER NORTHEAST/EAST CENTRAL IA AND
   FAR NORTHWEST IL AS OF 00Z. LARGE HAIL/BOUTS OF DAMAGING WINDS HAVE
   BEEN COMMON OVER THE PAST SEVERAL HOURS. AN ISOLATED TORNADO THREAT
   DOES CONTINUE...MAINLY WITH QUASI-DISCRETE STORMS INTERACTING WITH
   THE ROUGHLY NNW-SSE EFFECTIVE WARM FRONT/PRIOR OUTFLOW ACROSS FAR
   EASTERN IA/FAR NORTHWEST IL. HOWEVER...CURRENT TRENDS SUGGEST STORMS
   WILL CONTINUE TO CONGEAL/GROW UPSCALE THROUGH EARLY EVENING...WITH
   SOUTHWARD PROPAGATION ACROSS EASTERN IA AND NORTHWEST/NORTH CENTRAL
   IL. ALONG WITH CONTINUED SEVERE HAIL POTENTIAL...DAMAGING WINDS MAY
   INCREASE OVER THE NEXT FEW HOURS...WITH FORWARD PROPAGATION AIDED BY
   A MODERATELY UNSTABLE AIRMASS DOWNSTREAM AND RELATIVELY STRONG
   NORTHWESTERLY FLOW ALOFT /40 KT PER 00Z DAVENPORT RAOB/ WITH
   SOUTHERLY WINDS IN THE BOUNDARY LAYER. AN ADDITIONAL WATCH COULD
   EVENTUALLY BE NEEDED FOR PORTIONS OF NORTH CENTRAL IL/SOUTHEAST IA.
   
   OTHERWISE...IN THE WAKE OF THIS ACTIVITY...A FEW STRONGER STORMS MAY
   ATTEMPT TO DEVELOP FARTHER NORTH ALONG THE COLD FRONT ACROSS
   NORTHEAST IA/SOUTHEAST MN INTO SOUTHERN WI. HOWEVER...A CONVECTIVELY
   AIRMASS AND/OR MODEST BUOYANCY/MODEST CONVERGENCE SUGGESTS ANY
   SEVERE THREAT WILL BE MARGINAL/ISOLATED IN NATURE.
   
   ..GUYER.. 07/25/2009
   
   
   ATTN...WFO...LOT...ILX...MKX...DVN...ARX...DMX...
   
   LAT...LON   43109228 43379150 42679018 42338903 41828872 40558879
               40448996 41129188 43109228