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000 

WWUS20 KWNS 180727

SEL0

SPC WW 180727

ILZ000-INZ000-KYZ000-181400-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 720

NWS STORM PREDICTION CENTER NORMAN OK

225 AM CDT THU OCT 18 2007



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       SOUTHEAST ILLINOIS

       SOUTHWEST INDIANA

       WESTERN KENTUCKY



EFFECTIVE THIS THURSDAY MORNING FROM 225 AM UNTIL 900 AM CDT.



TORNADOES...HAIL TO 1 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS

TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 60 STATUTE

MILES EAST AND WEST OF A LINE FROM 45 MILES NORTH NORTHWEST OF

EVANSVILLE INDIANA TO 40 MILES SOUTH OF PADUCAH KENTUCKY.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU0).



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 716...WW 717...WW

718...WW 719...



DISCUSSION...SE MO MCS EXPECTED TO CONTINUE ENE INTO NARROW AXIS OF

MODEST SFC-BASED INSTABILITY ALONG THE MID MS AND LWR OH RVR VLYS.

CONVECTIVE SYSTEM IS LIKELY BEING INFLUENCED BY ASCENT ON SERN END

OF NEGATIVE TILT ERN KS UPR TROUGH.  WHILE SQLN SHOULD WEAKEN UPON

MOVING BEYOND INSTABILITY AXIS LATER THIS MORNING...CURRENT

CONDITIONS SUGGEST THAT EMBEDDED SUPERCELLS/SMALL SCALE BOWS SHOULD

REMAIN STRONG ENOUGH TO POSE A THREAT FOR DAMAGING WIND AND ISOLATED

TORNADOES INTO PARTS OF IL/WRN KY AND PERHAPS SW IND.



AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL

SURFACE AND ALOFT TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND

GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450.

MEAN STORM MOTION VECTOR 22045.





...CORFIDI

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