

000 

WWUS20 KWNS 020608

SEL7

SPC WW 020608

ARZ000-OKZ000-021300-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 247

NWS STORM PREDICTION CENTER NORMAN OK

110 AM CDT FRI MAY 2 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       NORTHWEST ARKANSAS

       CENTRAL AND EASTERN OKLAHOMA



EFFECTIVE THIS FRIDAY MORNING FROM 110 AM UNTIL 800 AM CDT.



TORNADOES...HAIL TO 2 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 90 STATUTE

MILES EAST AND WEST OF A LINE FROM 25 MILES NORTH NORTHWEST OF

GROVE OKLAHOMA TO 30 MILES SOUTHEAST OF ARDMORE OKLAHOMA.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU7).



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 246...



DISCUSSION...A STRONGLY FORCED SQUALL LINE WILL DEVELOP EWD FROM

CENTRAL INTO ERN OK AS A COLD FRONT SURGES EWD IN THE WAKE OF A

SURFACE LOW DEVELOPING NEWD INTO SE KS.  STRONG INSTABILITY IS STILL

PRESENT IN THE WARM SECTOR WITH VERY STEEP MID LEVEL LAPSE

RATES...THOUGH CONVECTIVE INHIBITION IS ALSO LARGE FOR BOUNDARY

LAYER PARCELS.  GIVEN THE VERY STRONG LOW-LEVEL SHEAR AND MOIST

BOUNDARY LAYER...THERE WILL STILL BE SOME POTENTIAL FOR ISOLATED

SPIN-UPS WITHIN THE LINE.  OTHERWISE...DAMAGING WINDS AND LARGE HAIL

SHOULD BE THE MOST COMMON THREATS.



AVIATION...TORNADOES AND 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

550. MEAN STORM MOTION VECTOR 27035.





...THOMPSON

