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038 

WWUS20 KWNS 112206

SEL2

SPC WW 112206

NEZ000-SDZ000-WYZ000-120300-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 632

NWS STORM PREDICTION CENTER NORMAN OK

405 PM MDT MON JUL 11 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       NORTHWEST NEBRASKA

       SOUTHWEST SOUTH DAKOTA

       EAST-CENTRAL WYOMING



EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 405 PM UNTIL 900

PM MDT.



TORNADOES...HAIL TO 2.5 INCHES IN DIAMETER...THUNDERSTORM WIND

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

AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 115 STATUTE

MILES EAST AND WEST OF A LINE FROM 30 MILES NORTH NORTHEAST OF

CHADRON NEBRASKA TO 20 MILES EAST OF ALLIANCE NEBRASKA.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU2).



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 628...WW 629...WW

630...WW 631...



DISCUSSION...MULTIPLE SUPERCELLS HAVE FORMED ALONG A WNW-ESE

ORIENTED BOUNDARY WHERE DEWPOINTS HAVE REMAINED IN THE 60S.

MOREOVER...LOCALLY BACKED SURFACE WINDS ARE RESULTING IN A CORRIDOR

OF ENHANCED LOW-LEVEL SHEAR.  AS SUCH...ONGOING STORMS WILL BE

CAPABLE OF A COUPLE TORNADOES IN ADDITION TO LARGE HAIL.



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

SURFACE AND ALOFT TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE

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

550. MEAN STORM MOTION VECTOR 28020.





...MEAD

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