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585 

WWUS20 KWNS 181040

SEL2

SPC WW 181040

ILZ000-MOZ000-181600-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 122

NWS STORM PREDICTION CENTER NORMAN OK

545 AM CDT THU APR 18 2013



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* TORNADO WATCH FOR PORTIONS OF

  WEST CENTRAL ILLINOIS

  EAST CENTRAL MISSOURI



* EFFECTIVE THIS THURSDAY MORNING FROM 545 AM UNTIL 1100 AM CDT.



* PRIMARY THREATS INCLUDE...

  SEVERAL TORNADOES POSSIBLE

  SEVERAL DAMAGING WIND GUSTS TO 70 MPH POSSIBLE

  A FEW LARGE HAIL EVENTS TO 1.5 INCHES IN DIAMETER POSSIBLE



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 45 STATUTE

MILES EAST AND WEST OF A LINE FROM 15 MILES SOUTHEAST OF

FARMINGTON MISSOURI TO 45 MILES NORTH NORTHEAST OF ALTON

ILLINOIS.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU2).



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 120...WW 121...



DISCUSSION...A SMALL CLUSTER OF THUNDERSTORMS IS INCREASING TO THE

SOUTHWEST OF STL.  THESE STORMS HAVE BEGUN SHOWING SUPERCELL

STRUCTURES.  VERY STRONG LOW LEVEL VERTICAL SHEAR COMBINED WITH

SUFFICIENT INSTABILITY MAY POSE A RISK OF DAMAGING WINDS AND

ISOLATED TORNADOES THIS MORNING AS THESE STORMS SPREAD ACROSS THE

WATCH AREA.



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

SURFACE AND ALOFT TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE

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

500. MEAN STORM MOTION VECTOR 23035.





...HART

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