MESOSCALE DISCUSSION 1257
   NWS STORM PREDICTION CENTER NORMAN OK
   1118 PM CDT SUN JUN 13 2004
   
   AREAS AFFECTED...NERN NEB...THROUGH PARTS OF WRN IA
   
   CONCERNING...SEVERE THUNDERSTORM POTENTIAL 
   
   VALID 140418Z - 140645Z
   
   THREAT FOR ISOLATED HAIL AND DAMAGING WIND GUSTS MAY SPREAD EWD
   THROUGH SERN SD...SWRN MN...NE NEB AND PARTS OF WRN IA NEXT FEW
   HOURS. AREA WILL CONTINUE TO BE MONITORED.
   
   SHORTWAVE TROUGH AND ASSOCIATED JET STREAK ARE MOVING EWD THROUGH
   CNTRL SD INTO N CNTRL NEB. MID LEVEL ASCENT ASSOCIATED WITH THIS
   FEATURE CONTINUES TO PROMOTE ELEVATED CONVECTIVE DEVELOPMENT ACROSS
   ERN SD...SWRN MN INTO EXTREME NRN NEB. SWLY LOW LEVEL JET IS
   FORECAST TO STRENGTHEN ACROSS SRN NEB IN RESPONSE TO THE APPROACHING
   SHORTWAVE TROUGH. THE 00Z RAOB DATA SHOWED AN AREA OF HIGHER THETA-E
   AIR OVER KS...AND AS THE LOW LEVEL JET STRENGTHENS AND
   VEERS...THETA-E ADVECTION WILL INCREASE THROUGH ERN NEB INTO PARTS
   OF IA INTO THE EARLY MORNING. THE RETURNING HIGHER THETA-E AIR BELOW
   COOLING MID LEVEL TEMPERATURES ACCOMPANYING THE SHORTWAVE TROUGH
   WILL SUPPORT DESTABILIZATION AND STEEPENING LAPSE RATES NEWD WITH
   TIME. GIVEN PRESENCE OF CAP AND MOSTLY MID LEVEL ASCENT EXPECTED IN
   THIS AREA...STORMS WILL NOT LIKELY TAP INTO THE BOUNDARY LAYER AIR.
   HOWEVER...STEEP LAPSE RATES IN PRESENCE OF MID LEVEL ASCENT WILL
   LIKELY CONTINUE TO PROMOTE MID LEVEL CONVECTIVE DEVELOPMENT NEXT
   SEVERAL HOURS. RELATIVELY DRY BOUNDARY LAYER MAY ENHANCE ISOLATED
   DAMAGING WIND THREAT WITH THE STRONGER STORMS.
   
   ..DIAL.. 06/14/2004
   
   
   ATTN...WFO...MPX...DMX...FSD...OAX...
   
   43279438 42649388 42089454 42059620 42239760 42809799
   43679746 44089567