MESOSCALE DISCUSSION 0702
   NWS STORM PREDICTION CENTER NORMAN OK
   0434 PM CDT SUN MAY 19 2013
   
   AREAS AFFECTED...S-CNTRL  AND NERN NEB
   
   CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 
   
   VALID 192134Z - 192230Z
   
   PROBABILITY OF WATCH ISSUANCE...80 PERCENT
   
   SUMMARY...THE THREAT FOR LARGE HAIL AND PERHAPS A TORNADO WILL
   PERSIST THROUGH THIS EVENING AND AN ADDITIONAL WATCH WILL BE
   REQUIRED.
   
   DISCUSSION...A NUMBER OF STRONG-SEVERE STORMS HAVE DEVELOPED THIS
   AFTERNOON OVER S-CNTRL NEB WHERE DEEP-LAYER ASCENT IS BEING
   AUGMENTED BY THE UPPER LOW SLOWLY LIFTING NEWD.  HERE...THE
   COMBINATION OF STEEP LOW- TO MIDLEVEL LAPSE RATES AND A MODESTLY
   MOIST BOUNDARY LAYER HAS YIELDED A MODERATELY UNSTABLE AIR MASS WITH
   MLCAPE OF 1000-1500 J/KG.  WHEN COUPLED WITH A VERTICALLY VEERING
   WIND PROFILE AND SUFFICIENT DEEP-LAYER SHEAR...THE SETUP WILL REMAIN
   SUPPORTIVE OF SUPERCELLS THROUGH THIS EVENING.  LARGE HAIL WILL BE
   THE PRIMARY HAZARD OWING TO THE STEEP LAPSE RATES AND COOL MIDLEVEL
   TEMPERATURES PROFILES.  HOWEVER...A TORNADO WILL BE POSSIBLE DUE TO
   BACKED LOW-LEVEL FLOW AND AMBIENT VERTICAL VORTICITY ASSOCIATED WITH
   THE DEEP-LAYER CYCLONE.
   
   ..MEAD/CORFIDI.. 05/19/2013
   
   
   ATTN...WFO...OAX...GID...LBF...
   
   LAT...LON   40329992 41179945 41789913 42029885 42089772 41139746
               40459807 40139850 40089937 40329992