MESOSCALE DISCUSSION 0556
   NWS STORM PREDICTION CENTER NORMAN OK
   0503 AM CDT TUE APR 24 2007
   
   AREAS AFFECTED...S-CNTRL NEB / N-CNTRL KS
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 170...
   
   VALID 241003Z - 241130Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 170
   CONTINUES.
   
   OVERALL SEVERE WEATHER POTENTIAL APPEARS TO BE DECREASING ACROSS
   REMAINING PORTION OF WW AREA FOR THE TIME BEING.  WW 170 WILL LIKELY
   BE ALLOWED TO EXPIRE AT 11Z.
   
   AS OF 0950Z...REGIONAL RADAR IMAGERY INDICATED A WIDESPREAD
   CONVECTIVE PRECIPITATION SHIELD OVER MUCH OF CNTRL AND ERN
   NEB...DRIVEN LARGELY BY STRONG LOW-LEVEL WAA AND ISENTROPIC ASCENT
   TO THE N OF WARM FRONT STRETCHING FROM THE S-CNTRL NEB/N-CNTRL KS
   BORDER SEWD INTO W-CNTRL MO.  WRN EXTENSION OF THIS BOUNDARY HAS
   BEEN MASKED BY A FAIRLY EXPANSIVE COLD POOL EMANATING FROM MORE
   INTENSE TSTMS CURRENTLY OVER S-CNTRL NEB INVOF OF EAR.  
   
   SURFACE OBSERVATIONS AND RUC FORECAST SOUNDINGS SUGGEST THAT THESE
   STORMS ARE ELEVATED WITHIN NRN EDGE OF STRONGER INSTABILITY WITH
   MUCAPES OF 1000-1500 J/KG.  THEREFORE...SOME POTENTIAL WILL EXIST
   FOR ISOLATED LARGE HAIL...PERHAPS EVEN LOCALLY STRONG WIND GUSTS AS
   THESE STORMS CONTINUE EWD THROUGH S-CNTRL NEB.
   
   GIVEN THAT PRIMARY LOW-LEVEL INSTABILITY AXIS IS FORECAST TO REMAIN
   OVER WRN INTO CNTRL KS THROUGH MID MORNING...STORMS SHOULD TEND TO
   WEAKEN AS THEY SHIFT E INTO SERN NEB.
   
   ..MEAD.. 04/24/2007
   
   
   ATTN...WFO...TOP...ICT...GID...LBF...DDC...GLD...
   
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