MESOSCALE DISCUSSION 0418
   NWS STORM PREDICTION CENTER NORMAN OK
   0659 PM CDT THU APR 09 2009
   
   AREAS AFFECTED...WRN 2/3 OF AR/SWRN AND S CENTRAL MO
   
   CONCERNING...TORNADO WATCH 123...
   
   VALID 092359Z - 100130Z
   
   THE SEVERE WEATHER THREAT FOR TORNADO WATCH 123 CONTINUES.
   
   SEVERE/TORNADO THREAT CONTINUES OVER SERN KS/SWRN MO/ERN OK/NWRN
   AR...AND WILL BEGIN TO SPREAD E OF THE WATCH IN THE NEXT HOUR OR SO.
    NEW WW WILL BE NEEDED.
   
   COLD FRONT CONTINUES SURGING EWD INTO ERN OK...AND CONTINUES TO
   APPROACH THE SLOWER-MOVING DRYLINE.  A BROKEN BAND OF STORMS -- WITH
   EMBEDDED SUPERCELLS -- JUST AHEAD OF THIS DRYLINE CONTINUES SHIFTING
   EWD ACROSS SERN KS/ERN OK AND INTO SWRN MO/WRN AR.  A TORNADO WAS
   RECENTLY REPORTED OVER LATIMER CO OK WITH A SUPERCELL WHICH IS NOW
   MOVING NEWD ACROSS WRN LE FLORE CO...ONE OF SEVERAL ROTATING STORMS
   ALONG THIS BAND.
   
   STORMS ARE MOVING THROUGH THE AXIS OF GREATEST INSTABILITY
   ATTM...WITH WEAKER INSTABILITY E OF THE CURRENT WATCH.  WITH DIURNAL
   COOLING OF THE BOUNDARY LAYER...ANY EWD DESTABILIZATION WILL BE
   LIMITED.  NONETHELESS...WITH STRONG LOW-LEVEL CONVERGENCE AHEAD OF
   THE FRONT/DRYLINE AND POTENT/COMPACT UPPER CIRCULATION CENTER OVER
   NWRN OK SHIFTING SLOWLY EWD...EXPECT STORMS TO CONTINUE WELL INTO
   THE EVENING.  WHILE THE THREAT FOR TORNADOES MAY GRADUALLY DECREASE
   OVERNIGHT...A CONTINUED DAMAGING WIND/HAIL THREAT WILL LIKELY
   WARRANT AN ADDITIONAL WW.
   
   ..GOSS.. 04/09/2009
   
   
   ATTN...WFO...LZK...SGF...SHV...EAX...TSA...TOP...ICT...FWD...
   
   LAT...LON   37829564 38169551 38479314 37369174 35199219 33829365
               33559535 34609538 36129494 37829564