MESOSCALE DISCUSSION 0723
   NWS STORM PREDICTION CENTER NORMAN OK
   0258 AM CDT SUN MAY 04 2003
   
   AREAS AFFECTED...NEB / SWRN IA / NWRN MO / NERN KS...
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 228...229...
   
   VALID 040758Z - 040930Z
   
   SEVERE THREAT -- MAINLY IN THE FORM OF MARGINALLY-SEVERE HAIL --
   WILL CONTINUE ACROSS ERN PORTIONS OF WW 228 AND MUCH OF WW 229. 
   SEVERE THREAT SHOULD BE EAST OF WW 228 BY 04/09Z...THUS THIS WATCH
   WILL BE ALLOWED TO EXPIRE AS SCHEDULED.  MEANWHILE...WW 229 WILL
   CONTINUE.
   
   ARCING LINE OF STORMS WITH A WELL-DEVELOPED COLD POOL AND MESOSCALE
   CYCLONIC CIRCULATION 40 E ANW CONTINUES MOVING EWD ACROSS NEB / WW
   228.  DESPITE BOWING SHAPE AND FAVORABLY STRONG DEEP-LAYER WIND
   FIELD...STORMS APPEAR TO BE ELEVATED ABOVE A STABLE BOUNDARY LAYER. 
   THIS SUGGESTS THAT THE PRIMARY SEVERE THREAT SHOULD REMAIN IN THE
   FORM OF HAIL.
   
   AHEAD OF THE LINE...CLUSTERS OF STORMS / SUPERCELLS CONTINUE MOVING
   NEWD ACROSS ERN NEB / NERN KS / NWRN NEB AND ARE NOW MOVING INTO
   SERN IA.  AGAIN...FAVORABLE DEEP-LAYER WIND FIELD BUT ELEVATED
   NATURE OF CONVECTION SUGGESTS HAIL WILL BE THE PRIMARY SEVERE THREAT
   ACROSS WW 229.
   
   AIRMASS EAST OF CURRENT WATCHES BECOMES INCREASINGLY STABLE WITH EWD
   EXTENT.  HOWEVER...LOW-LEVEL JET AXIS IS FORECAST TO SHIFT EWD WITH
   TIME WHICH WILL ALLOW SOME ELEVATED DESTABILIZATION OF AIRMASS EAST
   OF MO RIVER.  WE WILL CONTINUE TO MONITOR SERN IA / NERN MO EAST OF
   WW 229 FOR DEGREE OF DESTABILIZATION AND POTENTIAL FOR NEW WW LATER
   THIS MORNING.
   
   ..GOSS.. 05/04/2003
   
   
   ATTN...WFO...LSX...DVN...SGF...DMX...EAX...FSD...OAX...TOP...ICT...GID...LBF...
   
   42789905 42919785 42079312 41259173 39419154 38239207
   38099620 39669609 40750020 41609899