

552 

WWUS20 KWNS 112010

SEL9

SPC WW 112010

NEZ000-SDZ000-WYZ000-120300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 629

NWS STORM PREDICTION CENTER NORMAN OK

210 PM MDT MON JUL 11 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NEBRASKA PANHANDLE

       WESTERN SOUTH DAKOTA

       EASTERN WYOMING



EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 210 PM UNTIL 900

PM MDT.



HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70

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



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 75

STATUTE MILES EAST AND WEST OF A LINE FROM 80 MILES NORTHEAST OF

GILLETTE WYOMING TO 10 MILES EAST SOUTHEAST OF SIDNEY NEBRASKA.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU9).



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 627...WW 628...



DISCUSSION...STORMS ARE EXPECTED TO CONTINUE TO DEVELOP AND

INTENSIFY OVER PARTS OF ERN WY ALONG THE WRN EDGE OF THE

MOISTURE/INSTABILITY AXIS WHERE SELY UPSLOPE FLOW IS FOCUSED. AREA

VAD/PROFILERS INDICATE THAT WINDS VEER STRONGLY WITH HEIGHT

PROVIDING SUFFICIENT SHEAR FOR ORGANIZED CONVECTION INCLUDING A FEW

SUPERCELLS.  LARGE HAIL AND DAMAGING WINDS WILL BE POSSIBLE WITH

STRONGER CELLS...AND A BRIEF TORNADO OR TWO MAY ALSO OCCUR WITH ANY

BETTER DEFINED SUPERCELL THAT DEVELOPS AS STORMS MOVE SLOWLY NEWD.



AVIATION...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 450. MEAN STORM

MOTION VECTOR 24025.





...WEISS

