MESOSCALE DISCUSSION 0408
   NWS STORM PREDICTION CENTER NORMAN OK
   0510 PM CDT MON APR 02 2007
   
   AREAS AFFECTED...FAR SOUTHERN SD AND WESTERN/CENTRAL NEB
   
   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 
   
   VALID 022210Z - 022345Z
   
   AT LEAST AN ISOLATED SEVERE THREAT...IN THE FORM OF LARGE
   HAIL/STRONG WIND GUSTS...APPEARS LIKELY TO SPREAD EASTWARD ACROSS
   WESTERN NEB/FAR SOUTHERN SD INTO CENTRAL NEB THROUGH EARLY EVENING.
   WILL MONITOR FOR A POSSIBLE WATCH.
   
   WATER VAPOR IMAGERY FEATURES STOUT UPPER TROUGH TRANSITIONING
   EASTWARD FROM THE NORTHERN ROCKIES TO THE NORTHERN HIGH PLAINS LATE
   THIS AFTERNOON. AHEAD OF THIS FEATURE...WESTERN PERIPHERY OF LOW
   LEVEL MOISTURE TRANSPORT HAS ALLOWED BOUNDARY LAYER DEWPOINTS TO
   STEADILY INCREASE THROUGH THE 40S F DURING THE DAY ACROSS NEB. AS
   LARGE SCALE FORCING FOR ASCENT OVERSPREADS THE
   REGION...THUNDERSTORMS APPEAR LIKELY TO INCREASE IN
   COVERAGE/INTENSITY AS THEY DEVELOP EASTWARD THIS EVENING ACROSS
   NEB/FAR SOUTHERN SD. 
   
   RUC SOUNDINGS SUGGEST MUCAPE OF 500-1000 J/KG ACROSS THE
   REGION...MAXIMIZED ACROSS WEST CENTRAL/SOUTHWEST NEB. STRONG
   VERTICAL SHEAR /EVIDENT IN REGIONAL PROFILERS/ AND STEEPENING MID
   LEVEL LAPSE RATES WILL FAVOR LARGE HAIL POTENTIAL WITH THE STRONGEST
   STORMS...INCLUDING THE POSSIBILITY FOR ROTATING STORMS. IN
   ADDITION...GIVEN THE SHALLOW NATURE OF THE BETTER
   MOISTURE...RELATIVELY DRY AIR ABOVE THE BOUNDARY LAYER WILL FAVOR
   EVAPORATIVE COOLING AND THE POTENTIAL FOR STRONG DOWNDRAFTS. IN
   FACT...A 53 KNOT GUST WAS RECENTLY MEASURED AT PINE RIDGE SD.
   
   ..GUYER.. 04/02/2007
   
   
   ATTN...WFO...FSD...GID...LBF...UNR...
   
   43160220 43429984 42079857 41109843 40409987 40980184
   41700239