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URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 741

NWS STORM PREDICTION CENTER NORMAN OK

750 PM CDT SUN AUG 7 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       CENTRAL AND EASTERN NEBRASKA

       SOUTHERN SOUTH DAKOTA



EFFECTIVE THIS SUNDAY NIGHT AND MONDAY MORNING FROM 750 PM UNTIL

300 AM CDT.



HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 80

MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 80

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 45 MILES NORTHWEST

OF MULLEN NEBRASKA TO 15 MILES SOUTH OF OMAHA NEBRASKA.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU1).



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 736...WW 737...WW

738...WW 739...WW 740...



DISCUSSION...COMPLEX MCS NOW EVOLVING INVOF THE NEB/SD BORDER NEAR

VTN EXPECTED TO MOVE MAINLY ESE TO SE THROUGH LATER TNGT/EARLY MON.

ANOTHER MCS MAY EVOLVE FROM STORMS NOW E OF LBF AS THAT ACTIVITY

ENCOUNTERS MOIST NOCTURNALLY ENHANCED SSWLY LLJ.  COMBINATION OF

STRONG INSTABILITY...40+ KT WNWLY MID LVL FLOW...AND UPR

DIFFLUENCE/JET EXIT REGION ASCENT ASSOCIATED WITH JET STREAK

EMERGING FROM THE CNTRL RCKYS SUGGEST GOOD POSSIBILITY OF BOWING

SEGMENTS WITH HIGH WIND AND SVR HAIL.



AVIATION...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 600. MEAN STORM

MOTION VECTOR 30030.





...CORFIDI

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