URGENT - IMMEDIATE BROADCAST REQUESTED
   TORNADO WATCH NUMBER 724
   NWS STORM PREDICTION CENTER NORMAN OK
   325 PM CDT THU OCT 18 2007
   
   THE NWS STORM PREDICTION CENTER HAS ISSUED A
   TORNADO WATCH FOR PORTIONS OF 
   
          PART OF SOUTHERN AND EASTERN ILLINOIS
          MUCH OF INDIANA
          MUCH OF LOWER MICHIGAN
          LAKE HURON
          LAKE MICHIGAN
   
   EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 325 PM UNTIL
   1100 PM CDT.
   
   TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND
   GUSTS TO 90 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
   AREAS.
   
   THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 95 STATUTE
   MILES EAST AND WEST OF A LINE FROM 45 MILES NORTH NORTHEAST OF
   ALPENA MICHIGAN TO 40 MILES SOUTHEAST OF MOUNT VERNON ILLINOIS. 
   FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
   OUTLINE UPDATE (WOUS64 KWNS WOU4).
   
   REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
   TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
   AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
   THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
   AND POSSIBLE WARNINGS.
   
   OTHER WATCH INFORMATION...CONTINUE...WW 722...WW 723...
   
   DISCUSSION...VERY STRONG WIND FIELDS ROTATING NEWD ACROSS MID MS
   VALLEY INTO GREAT LAKES TO E OF DEEP LOW OVER MN.  AIR MASS NOW
   MDTLY UNSTABLE AND WITH LITTLE REMAINING CINH.  STEEP LAPSE RATES
   HAVE DEVELOPED IN THE MOIST AXIS WHICH WILL FURTHER ENHANCE WIND
   DAMAGE POTENTIAL AS STORMS DEVELOP INTO LINES AND BOWS. 
   ADDITIONALLY SUPERCELLS WILL BE LIKELY WITH POTENTIAL FOR STRONG
   TORNADOES.
   
   AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
   SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE
   WIND GUSTS TO 80 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
   500. MEAN STORM MOTION VECTOR 22045.
   
   
   ...HALES

Probabilities:

Tornadoes
Probability of 2 or more tornadoes High (70%)
Probability of 1 or more strong (F2-F5) tornadoes Mod (40%)

Wind
Probability of 10 or more severe wind events High (>95%)
Probability of 1 or more wind events > 65 knots High (90%)

Hail
Probability of 10 or more severe hail events Mod (50%)
Probability of 1 or more hailstones > 2 inches Mod (30%)

Combined Severe Hail/Wind
Probability of 6 or more combined severe hail/wind events High (>95%)