

671 

WWUS20 KWNS 230220

SEL9

SPC WW 230220

IAZ000-MNZ000-NEZ000-SDZ000-230900-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 349

NWS STORM PREDICTION CENTER NORMAN OK

915 PM CDT SAT JUN 22 2013



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

  NORTHWEST IOWA

  SOUTHWEST MINNESOTA

  NORTHEAST NEBRASKA

  SOUTHEAST SOUTH DAKOTA



* EFFECTIVE THIS SATURDAY NIGHT AND SUNDAY MORNING FROM 915 PM

  UNTIL 400 AM CDT.



* PRIMARY THREATS INCLUDE...

  SEVERAL DAMAGING WIND GUSTS TO 70 MPH POSSIBLE

  SEVERAL LARGE HAIL EVENTS TO 1.5 INCHES IN DIAMETER POSSIBLE



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 65

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 10 MILES SOUTH

SOUTHWEST OF CHAMBERLAIN SOUTH DAKOTA TO 35 MILES NORTH NORTHEAST

OF SPENCER IOWA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU9).



PRECAUTIONARY/PREPAREDNESS ACTIONS...



REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE

FAVORABLE FOR 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. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY

DO PRODUCE TORNADOES.



&&



OTHER WATCH INFORMATION...CONTINUE...WW 345...WW 346...WW

347...WW 348...



DISCUSSION...WAA TSTMS EXPECTED TO INCREASE IN COVERAGE/STRENGTH

ALONG ELEVATED WSW-ENE FRONTAL ZONE NOW OVER SE SD. OTHER STORMS MAY

MOVE/DEVELOP GENERALLY ENE FROM MCS EXPECTED TO EVOLVE OVER THE NEXT

FEW HRS IN N CNTRL NEB. DEEP SHEAR AND ASCENT SHOULD INCREASE WITH

TIME IN RESPONSE TO THE CONTINUED ENE MOTION OF MAIN NRN RCKYS UPR

IMPULSE...TO THE CONTINUED NE MOTION OF LEAD IMPULSE NOW IN W CNTRL

NEB...AND TO NOCTURNAL STRENGTHENING OF SSWLY LLJ. SETUP COULD YIELD

A COMPLEX MIX OF STRONG TO SVR STORM CLUSTERS...SOME OF WHICH COULD

YIELD HIGH WIND...SVR HAIL...AND POSSIBLY A TORNADO THROUGH EARLY

SUN.



AVIATION...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 25030.





...CORFIDI

