

619 

WWUS20 KWNS 290851

SEL8

SPC WW 290851

OKZ000-TXZ000-291600-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 208

NWS STORM PREDICTION CENTER NORMAN OK

350 AM CDT WED APR 29 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       WESTERN AND SOUTHERN OKLAHOMA

       NORTHWEST TEXAS



EFFECTIVE THIS WEDNESDAY MORNING FROM 350 AM UNTIL 1100 AM CDT.



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 70

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 70 MILES WEST OF

CHILDRESS TEXAS TO 25 MILES NORTH NORTHEAST OF ARDMORE OKLAHOMA.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU8).



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...THIS SEVERE THUNDERSTORM WATCH REPLACES

SEVERE THUNDERSTORM WATCH NUMBER 206. WATCH NUMBER 206 WILL NOT

BE IN EFFECT AFTER 350 AM CDT. CONTINUE...WW 207...



DISCUSSION...SLIGHTLY ELEVATED SUSTAINED STORM CLUSTERS/WEAK

SUPERCELLS EXPECTED TO MOVE/DEVELOP GENERALLY ENE THROUGH LATER THIS

MORNING AS 30-40 KT SLY LLJ CONTINUES TO MOISTEN LAYER ABOVE SHALLOW

COOL DOME.  RELATIVE WEAKNESS OF FLOW IN THE 700-500 MB LAYER

EXPECTED TO SOMEWHAT LIMIT STORM ORGANIZATION/STRENGTH...BUT

POTENTIAL WILL NEVERTHELESS EXIST FOR SMALL BOWING SEGMENTS/LEWPS

WITH SVR HAIL...DMG WIND...AND PERHAPS AN ISOLD TORNADO GIVEN

QUALITY OF ELEVATED MOIST INFLOW /PW AOA 1.25 INCHES/.



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 500. MEAN STORM

MOTION VECTOR 25020.





...CORFIDI

