MESOSCALE DISCUSSION 0263
   NWS STORM PREDICTION CENTER NORMAN OK
   0709 PM CDT THU APR 09 2015

   AREAS AFFECTED...NORTH-CENTRAL/NORTHEAST IL AND EXTREME SOUTHEAST WI

   CONCERNING...TORNADO WATCH 41...

   VALID 100009Z - 100145Z

   THE SEVERE WEATHER THREAT FOR TORNADO WATCH 41 CONTINUES.

   SUMMARY...THE POTENTIAL FOR TORNADOES AND SEVERE HAIL/DAMAGING WINDS
   CONTINUES ACROSS NORTHERN IL/POSSIBLY FAR SOUTHEAST WI...BUT
   PARTICULARLY IN NORTHERN IL AREAS NEAR THE WARM FRONT NEAR
   I-88/REAGAN TOLLWAY AND I-39/I-90 CORRIDORS. WITH A DAMAGING TORNADO
   ONGOING SOUTH OF ROCKFORD AS OF 7PM CDT...STRONG TORNADOES WILL
   REMAIN A POSSIBILITY OVER THE NEXT HOUR OR TWO INTO ADDITIONAL PARTS
   OF FAR NORTHEAST IL.

   DISCUSSION...SEMI-DISCRETE SUPERCELLS CONTINUE TO DEVELOP/QUICKLY
   MATURE ACROSS NORTH-CENTRAL/NORTHEAST IL IMMEDIATELY AHEAD OF AN
   INCREASINGLY MORE COMPLEX HP-TO-ASYMMETRIC MCS TRANSITIONAL
   STORM-MODE ACROSS NORTHWEST IL AS OF 00Z. NEAR THE WARM FRONT ACROSS
   NORTHERN IL...ADEQUATE LOW-LEVEL MOISTURE /LOWER 60S F SURFACE
   DEWPOINTS/ EXISTS IN CONJUNCTION WITH RELATIVELY STRONG LOW-LEVEL
   SHEAR/SRH...ACCENTUATED BY A MODEST TREND TOWARD LOW-LEVEL BACKING
   ACROSS NORTHEAST IL VIA MASS RESPONSE TO THE UPSTREAM DEEPENING
   SURFACE LOW. INTENSE SUPERCELLS IN GENERAL VICINITY OF
   I-88/I-90/I-39 CORRIDORS INTERACTING/CROSSING THE WARM FRONT ARE
   MOST LIKELY TO PRODUCE STRONG TORNADOES IN THE SHORT-TERM.

   ..GUYER.. 04/10/2015


   ATTN...WFO...LOT...MKX...

   LAT...LON   41898934 42378921 42618828 42548792 42008800 41898934