MESOSCALE DISCUSSION 1037
   NWS STORM PREDICTION CENTER NORMAN OK
   1038 PM CDT MON MAY 30 2011
   
   AREAS AFFECTED...PORTIONS KS...ERN NEB...WRN IA...EXTREME SERN SD.
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 405...
   
   VALID 310338Z - 310545Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 405
   CONTINUES.
   
   SVR SQUALL LINE WILL CONTINUE TO MOVE EWD ACROSS WW AREA...WITH
   BACKBUILDING SWD OVER KS...AS PART OF PROBABLE SERIAL DERECHO EVENT
   THAT ALSO EXTENDS NNEWD OVER WRN MN.  WW MAY BE CLEARED BEHIND TSTM
   BAND...WHERE POSTFRONTAL DECLINE IN LOW-LEVEL THETAE IS UNDERWAY. 
   SOME COUNTIES MAY BE ADDED TO WW ACROSS S-CENTRAL/SERN KS IN ICT/DDC
   COUNTY WARNING AREAS. 
   
   SIGNIFICANT PRESSURE RISES CONTINUE TO BE ANALYZED IN POSTFRONTAL
   ENVIRONMENT...I.E. 10-11 MB PER 2 HOUR RISES ANALYZED INVOF KS/NEB
   BORDER.  AS SUCH...EXPANSIVE FRONTAL/OUTFLOW AIR MASS WILL CONTINUE
   TO REINFORCE CONVECTIVE WIND THREAT ACROSS THIS REGION...WITH
   MEASURED SVR GUSTS ALREADY HAVING BEEN RECORDED AT SEVERAL LOCALES. 
   THIS INCLUDES 64-KT GUST AT GRI AT 0230Z..AND 59 KT JUST E OF THERE
   AT MYP.  FOR A FEW MORE HOURS AT LEAST...INTENSE CONVERGENCE/ASCENT
   ALONG LEADING EDGE OF COLD-POOL SLAB SHOULD WILL CONTINUE TO
   OVERCOME STG CINH EVIDENT IN 00Z WARM-SECTOR RAOBS.  FOREGOING AIR
   MASS IS CHARACTERIZED BY MID-UPPER 60S SFC DEW POINTS..CONTRIBUTING
   TO MLCAPE GENERALLY 1500-2500 J/KG...WITH 40-50 KT EFFECTIVE SHEAR
   IN MODIFIED FCST SOUNDINGS.  MAIN UNCERTAINTY ATTM IS IN HOW FAR S
   BACKBUILDING WILL TAKE PLACE...GIVEN PROGRESSIVELY GREATER DISTANCE
   FROM STRONGEST DEEP-LAYER FORCING AND LIKELIHOOD OF MORE SHALLOW
   COLD-FRONTAL SLOPE WITH SWD EXTENT.  IR IMAGERY INDICATES COOLING
   CLOUD TOPS AS FAR S AS KS/OK BORDER SSW DDC...JUST S OF WHERE COLD
   SURGE...WEAKER COLD FRONT/CONFLUENCE LINE...AND DRYLINE INTERSECT.
   
   ..EDWARDS.. 05/31/2011
   
   
   ATTN...WFO...DMX...FSD...OAX...TOP...ICT...GID...DDC...
   
   LAT...LON   37320024 39809866 42779714 42709681 42979678 42919537
               41569551 38919660 38189737 38159797 37069864 37320024