

033 

WWUS20 KWNS 152257

SEL6

SPC WW 152257

OKZ000-160500-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 666

NWS STORM PREDICTION CENTER NORMAN OK

555 PM CDT WED SEP 15 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHWEST AND NORTHERN OKLAHOMA



EFFECTIVE THIS WEDNESDAY AFTERNOON FROM 555 PM UNTIL MIDNIGHT CDT.



HAIL TO 2.5 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 85

STATUTE MILES EAST AND WEST OF A LINE FROM 20 MILES NORTH

NORTHEAST OF PONCA CITY OKLAHOMA TO 40 MILES SOUTH SOUTHWEST OF

ENID OKLAHOMA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU6).



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 664...WW 665...



DISCUSSION...THUNDERSTORM DEVELOPMENT IS UNDERWAY ALONG A PRONOUNCED

SURFACE TROUGH/DRYLINE ACROSS NW OK.  A FEW SUSTAINED STORMS WITH

SUPERCELL CHARACTERISTICS ARE PROBABLE IN THE NEXT COUPLE OF HOURS

GIVEN THE STRONG ASCENT ON THE BOUNDARY...AND A STORM ENVIRONMENT

WITH EFFECTIVE BULK SHEAR OF 35-45 KT AND MLCAPE IN EXCESS OF 2000

J/KG.  OTHER SEVERE STORMS NEAR ICT WILL ALSO CONTINUE TO MOVE SEWD

TOWARD THE OK BORDER...POTENTIALLY REACHING THE OSAGE COUNTY AREA

AROUND 01Z.  LARGE HAIL AND DAMAGING WINDS WILL BE THE PRIMARY

SEVERE STORM THREATS UNTIL LATE EVENING WHEN THE BOUNDARY LAYER

COOLS AND THE CAP STRENGTHENS.



AVIATION...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 30020.





...THOMPSON

