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WWUS20 KWNS 181336

SEL3

SPC WW 181336

ILZ000-INZ000-MIZ000-OHZ000-LMZ000-182100-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 123

NWS STORM PREDICTION CENTER NORMAN OK

935 AM EDT THU APR 18 2013



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* TORNADO WATCH FOR PORTIONS OF

  EASTERN ILLINOIS

  CENTRAL AND EASTERN INDIANA

  SOUTHERN LOWER MICHIGAN

  NORTHWEST OHIO OHIO

  LAKE MICHIGAN



* EFFECTIVE THIS THURSDAY MORNING AND AFTERNOON FROM 935 AM UNTIL

  500 PM EDT.



...THIS IS A PARTICULARLY DANGEROUS SITUATION...



* PRIMARY THREATS INCLUDE...

  SEVERAL INTENSE TORNADOES LIKELY

  SEVERAL SIGNIFICANT DAMAGING WIND GUSTS TO 80 MPH POSSIBLE

  A FEW VERY LARGE HAIL EVENTS TO 2 INCHES IN DIAMETER POSSIBLE



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 75 STATUTE

MILES EAST AND WEST OF A LINE FROM 65 MILES EAST NORTHEAST OF

SOUTH BEND INDIANA TO 60 MILES SOUTH SOUTHWEST OF TERRE HAUTE

INDIANA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU3).



PRECAUTIONARY/PREPAREDNESS ACTIONS...



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 122...



DISCUSSION...DISCRETE SUPERCELL DEVELOPMENT IS POSSIBLE AHEAD OF THE

INTENSIFYING PRE-FRONTAL SQUALL LINE THAT WILL RAPIDLY MOVE

NORTHEASTWARD ACROSS THE WATCH AREA THIS MORNING.  GIVEN THE

STRENGTH OF THE LOW-LEVEL SHEAR...A FEW TORNADOES ARE

POSSIBLE...BOTH IN SUPERCELLS AND WITHIN MESO VORTICES EMBEDDED

WITHIN THE LINE.  ACTIVITY MAY BE CAPABLE OF PRODUCING STRONG TO

LOCALLY EXTREME WIND DAMAGE...REGARDLESS OF WHETHER TORNADIC OR

STRAIGHT LINE IN NATURE,



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

SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE

WIND GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO

500. MEAN STORM MOTION VECTOR 24050.





...KERR

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