MESOSCALE DISCUSSION 2111
   NWS STORM PREDICTION CENTER NORMAN OK
   1023 AM CDT THU OCT 15 2009
   
   AREAS AFFECTED...NRN/NERN LA AND WEST CENTRAL/SWRN MS
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 769...
   
   VALID 151523Z - 151630Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 769
   CONTINUES.
   
   LATEST TRENDS IN REGIONAL RADAR IMAGERY HAVE SHOWN A DECREASE IN
   FORWARD SPEED OF THE MCS WHICH IS CURRENTLY TRACKING SEWD THROUGH
   NRN/NERN LA.  THE LEADING EDGE OF THE MCS HAS BECOME MORE PARALLEL
   TO VEERING W/NWLY LOW LEVEL WINDS IN RESPONSE TO THE SEWD
   TRANSLATION OF A LEAD IMPULSE AHEAD OF AN AMPLIFYING UPPER LONGWAVE
   TROUGH INTO THE MS VALLEY REGION.  THE RESULTANT LACK OF STRONGER
   LOW LEVEL CONVERGENCE AND WAA SUGGEST OVERALL STORM INTENSITIES
   SHOULD TEND TO REMAIN LESS THAN OBSERVED EARLIER THIS MORNING...
   DESPITE THE PRESENCE OF A VERY MOIST AND MODERATELY UNSTABLE/
   STRONGLY SHEARED ENVIRONMENT.
   
   IN THE SHORT TERM...THE MAIN THREAT SHOULD BE HEAVY RAINFALL RATES
   GIVEN PRECIPITABLE WATER VALUES OF 1.8-2.0 INCHES AND SLOWER STORM
   MOVEMENT TRAINING TOWARD THE ESE AS NEW UPDRAFTS DEVELOP ALONG THE
   SWRN PERIPHERY OF THE MCS.
   
   ..PETERS.. 10/15/2009
   
   
   ATTN...WFO...JAN...LIX...LCH...SHV...
   
   LAT...LON   32519347 32619305 32709264 32859204 32979138 32979087
               32659088 32479063 31369066 31129152 31079159 31419231
               31389327 31899359 32519347