MESOSCALE DISCUSSION 1574
   NWS STORM PREDICTION CENTER NORMAN OK
   0955 AM CDT MON JUL 11 2011
   
   AREAS AFFECTED...NORTHERN INDIANA/SOUTHERN LOWER MI/NORTHERN OH
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 625...626...627...
   
   VALID 111455Z - 111600Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH
   625...626...627...CONTINUES.
   
   SEVERE THUNDERSTORM WATCHES 625/626/627 CONTINUE UNTIL 17Z/18Z/21Z
   RESPECTIVELY. WIDESPREAD WIND DAMAGE WILL LIKELY CONTINUE ACROSS
   SOUTHERN LOWER MI/NORTHERN NORTHERN INDIANA IN THE SHORT-TERM...WITH
   AN INCREASING SEVERE THREAT INTO THE AFTERNOON ACROSS NORTHERN OH.
   
   AS OF 1445Z...A DERECHO-PRODUCING SQUALL LINE CONTINUES TO STEADILY
   RACE EASTWARD ACROSS SOUTHERN LOWER MI/FAR NORTHERN INDIANA
   INCLUDING A CORRIDOR FROM NEAR GRAND RAPIDS MI TO THE SOUTH BEND
   INDIANA VICINITY. THIS ONGOING/FAST-MOVING QUASI-LINEAR SYSTEM WILL
   ENCOUNTER A LOCALLY MORE DESTABILIZED BOUNDARY LAYER ACROSS LOWER MI
   IN THE WAKE OF THE PREVIOUS SQUALL LINE. HOWEVER...THE EXISTING COLD
   POOL/DEGREE OF QLCS ORGANIZATION AND A 50+ KT FORWARD PROPAGATION
   WILL LIKELY CONTINUE TO YIELD WIDESPREAD DAMAGING WINDS NONETHELESS
   INTO EARLY AFTERNOON.
   
   OTHERWISE...THE BOUNDARY LAYER CONTINUES TO AGGRESSIVELY
   HEAT/DESTABILIZE TO THE SOUTH OF THE EXISTING SQUALL
   LINES...INCLUDING A CORRIDOR FROM NORTH-CENTRAL INDIANA INTO MUCH OF
   NORTHERN/CENTRAL OH. THE SOUTHERN EDGE OF THE EXISTING QLCS OVER
   NORTHERN INDIANA MAY THRIVE IN THIS ENVIRONMENT...WITH
   ADDITIONAL/PERIPHERAL DEEP CONVECTIVE DEVELOPMENT INTO THE AFTERNOON
   FARTHER SOUTH. SUBSEQUENT MULTICELLULAR/QUASI-LINEAR ORGANIZATION IS
   PROBABLE ON THE SOUTHERN FRINGE OF STRONGER WESTERLIES ALOFT...AND
   DAMAGING WINDS/SEVERE HAIL WILL BE THE PRIMARY HAZARDS.
   
   ..GUYER.. 07/11/2011
   
   
   ATTN...WFO...PBZ...CLE...ILN...DTX...IWX...GRR...IND...LOT...
   
   LAT...LON   41148743 41718665 42638627 43298604 43208414 42158320
               41538308 41228079 40518064 39928188 40218672 41148743