MESOSCALE DISCUSSION 1714
   NWS STORM PREDICTION CENTER NORMAN OK
   0545 PM CDT TUE AUG 13 2013

   AREAS AFFECTED...WRN SD...FAR NRN NEB/NERN WY

   CONCERNING...SEVERE THUNDERSTORM WATCH 491...

   VALID 132245Z - 140015Z

   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 491
   CONTINUES.

   SUMMARY...SEVERE POTENTIAL HAS DIMINISHED SUBSTANTIALLY DURING THE
   PAST HOUR AND WILL LIKELY REMAIN MARGINAL THIS EVENING. IF CURRENT
   OBSERVATIONAL TRENDS PERSIST...MUCH OF WW 491 MAY BE CANCELLED PRIOR
   TO 03Z SCHEDULED EXPIRATION.

   DISCUSSION...REFLECTIVITY GRADIENT ASSOCIATED WITH A SMALL LINE
   SEGMENT ACROSS MEADE AND LAWRENCE COUNTIES SD HAD RELAXED
   CONSIDERABLY AS CONVECTIVE OUTFLOW SURGED OUT WELL AHEAD OF THE LINE
   DURING THE PAST HOUR. PRIOR TO OUTFLOW PASSAGE AT THE UDX
   RADAR...VWP DATA ONLY SAMPLED AROUND 20-25 KT OF 0-6 KM SHEAR AND
   ANVILS IN SATELLITE IMAGERY HAVE SPREAD OUT ALMOST EVENLY IN ALL
   DIRECTIONS...INDICATIVE OF THE WEAKLY SHEARED ENVIRONMENT. IN
   ADDITION...WITH JUST A NARROW CORRIDOR OF UPPER 50S TO LOWER 60S
   EXTENDING SEWD INTO N-CNTRL NEB...MLCAPE HAS PEAKED NEAR 1500 J/KG.
   SOME CHANCE DOES EXIST THAT CONVECTION COULD INTENSIFY IF RENEWED
   UPDRAFTS CAN FORM ALONG THIS AXIS GIVEN THE PRESENCE OF AN MCV.
   STILL...GIVEN THE AFOREMENTIONED KINEMATIC SETUP...ANY SEVERE WIND
   THREAT SHOULD STAY LOCALIZED.

   ..GRAMS.. 08/13/2013


   ATTN...WFO...ABR...LBF...UNR...CYS...

   LAT...LON   44490267 45030237 44940097 44010005 43119979 42460010
               42390056 42390149 42630301 43010375 43680453 44400459
               44490267