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142 

WWUS20 KWNS 180437

SEL9

SPC WW 180437

IAZ000-MNZ000-NEZ000-SDZ000-181000-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 319

NWS STORM PREDICTION CENTER NORMAN OK

1135 PM CDT TUE JUN 17 2014



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* TORNADO WATCH FOR PORTIONS OF

  NORTHWEST AND NORTH CENTRAL IOWA

  SOUTHWEST AND SOUTH CENTRAL MINNESOTA

  EXTREME NORTHEAST NEBRASKA

  SOUTHEAST SOUTH DAKOTA



* EFFECTIVE THIS TUESDAY NIGHT AND WEDNESDAY MORNING FROM 1135 PM

  UNTIL 500 AM CDT.



* PRIMARY THREATS INCLUDE...

  A FEW TORNADOES POSSIBLE

  SCATTERED LARGE HAIL AND ISOLATED VERY LARGE HAIL EVENTS TO 2

    INCHES IN DIAMETER POSSIBLE

  SCATTERED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 65 STATUTE

MILES NORTH AND SOUTH OF A LINE FROM 30 MILES SOUTHWEST OF SIOUX

FALLS SOUTH DAKOTA TO 20 MILES EAST OF MASON CITY IOWA.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU9).



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...THIS TORNADO WATCH REPLACES TORNADO

WATCH NUMBER 315. WATCH NUMBER 315 WILL NOT BE IN EFFECT AFTER

1135 PM CDT. CONTINUE...WW 316...WW 317...WW 318...



DISCUSSION...CLUSTERS OF SUPERCELLS WILL PERSIST FOR A FEW HOURS IN

THE WARM ADVECTION REGIME ALONG A STATIONARY FRONT...WHERE THE LOW

LEVELS REMAIN MOIST AND STRONG INSTABILITY IS ROOTED AT THE SURFACE.

VERTICAL SHEAR IS FAVORABLE FOR ROTATING STORMS AND THE POTENTIAL

FOR TORNADOES...ESPECIALLY IN THE NEXT 1-2 HOURS.

EVENTUALLY...STORMS ARE EXPECTED TO CONGEAL INTO A LARGER

CLUSTER/MCS WITH AN ATTENDANT RISK FOR DAMAGING WINDS AND LARGE

HAIL.



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

SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE

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

550. MEAN STORM MOTION VECTOR 29015.





...THOMPSON

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