MESOSCALE DISCUSSION 0507
   NWS STORM PREDICTION CENTER NORMAN OK
   0933 PM CDT FRI APR 17 2009
   
   AREAS AFFECTED...PARTS OF SWRN KS / WRN OK / WRN N-CNTRL TX
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 163...
   
   VALID 180233Z - 180300Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 163
   CONTINUES.
   
   A DECREASING SEVERE THREAT IS ENSUING ACROSS PARTS OF SWRN KS / WRN
   OK / WRN N-CNTRL TX.  WW WILL BE ALLOWED TO EXPIRE AT 03Z.
   
   SURFACE ANALYSIS SHOWS RELATIVELY LITTLE MOVEMENT IN SURFACE
   FEATURES OVER THE PAST FEW HOURS AS DRYLINE/OCCLUDED FRONT BOUNDARY
   ARCS FROM SERN CO INTO THE TX LOW ROLLING PLAINS REMAINS
   QUASI-STATIONARY.  TRENDS IN RADAR MOSAIC SHOW THE STRONGER CORES
   WEAKENING SUBSTANTIALLY IN THE PAST HR...WHICH IS PROBABLY DUE IN
   PART TO DIURNAL STABILIZATION OVER THE REGION.  THE MOST ROBUST
   UPDRAFTS CURRENTLY RESIDE OVER PARTS OF WRN OK AS OF 0230Z...BUT AS
   THESE STORMS AND THE ONES TO THE S OVER WRN N-CNTRL TX CONTINUE TO
   MOVE E AWAY FROM THERMAL RIDGE/INSTABILITY AXIS...WILL PROBABLY
   RESULT IN THESE STORMS WEAKENING FURTHER IN THE SHORT TERM.
   
   ..SMITH.. 04/18/2009
   
   
   ATTN...WFO...OUN...DDC...SJT...LUB...AMA...PUB...
   
   LAT...LON   34589931 33209923 32319939 32250000 32960032 34370050
               36040122 36930199 37580260 38060246 37870127 37230031
               36539979 35299940 34589931