MESOSCALE DISCUSSION 0236
   NWS STORM PREDICTION CENTER NORMAN OK
   1024 AM CST THU MAR 01 2007
   
   AREAS AFFECTED...NORTHERN IL/NORTHWEST INDIANA
   
   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 
   
   VALID 011624Z - 011800Z
   
   AT LEAST AN ISOLATED SEVERE THREAT IS LIKELY TO STEADILY
   DEVELOP/INCREASE ACROSS NORTHERN IL INTO NORTHWEST INDIANA THROUGH
   EARLY AFTERNOON. A WATCH MAY BE NEEDED WITHIN THE NEXT HOUR OR SO.
   
   ON EASTERN PERIPHERY OF STACKED LOW OVER SOUTHERN IA...AIRMASS
   CONTINUES TO GRADUALLY DESTABILIZE ACROSS NORTHERN IL ON THE FRINGE
   OF THE SURGING MID LEVEL DRY SLOT. WHILE THE EXISTING LINE OF
   STRONG/SEVERE STORMS CONTINUES TO STEADILY PUSH EASTWARD ACROSS
   CENTRAL IL...ARCING CUMULUS HAS BEEN DEVELOPING UPSTREAM/TO THE WEST
   OVER THE PAST HALF HOUR...NAMELY FROM FAR SOUTHEAST IA TO NEAR ST
   LOUIS AS OF 1615Z. AS STORMS FILL-IN/INCREASE IN AREAL COVERAGE
   THROUGH EARLY AFTERNOON...THE PRIMARY HAZARD WILL LIKELY BE LARGE
   HAIL WITH NORTH EXTENT ACROSS NORTHERN IL AND NORTHWEST INDIANA.
   HOWEVER...POTENTIAL WILL ALSO EXIST FOR STRONG WIND GUSTS AND
   PERHAPS AN ISOLATED TORNADO OR TWO WHERE CONVECTION IS NEAR SURFACE
   BASED AMIDST BACKED SOUTHEASTERLY LOW LEVEL WINDS ALONG/AHEAD OF THE
   LOW LEVEL FRONTAL OCCLUSION.
   
   ..GUYER.. 03/01/2007
   
   
   ATTN...WFO...IWX...IND...LOT...ILX...LSX...DVN...
   
   41259039 41978927 42128795 41828676 41558611 41158575
   40688609 40358696 40248866 39549011 40109101