MESOSCALE DISCUSSION 0870
   NWS STORM PREDICTION CENTER NORMAN OK
   0519 PM CDT WED MAY 23 2007
   
   AREAS AFFECTED...PARTS OF CENTRAL AND NERN KS/SERN NEB/EXTREME NWRN
   MO/SWRN IA
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 290...
   
   VALID 232219Z - 232345Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 290
   CONTINUES.
   
   GREATEST POTENTIAL FOR SEVERE STORMS IS EXPECTED TO CONTINUE FROM
   SOUTH CENTRAL KS NEWD THROUGH NERN KS/SWRN IA WITHIN WW 290. 
   STRONGEST LOW LEVEL INFLOW /SLY LLJ AT 30 KT/ WILL BE MAINTAINED
   INTO THIS EXTENDED AREA OF STORMS WITH DEEP LAYER SHEAR VECTORS
   FAVORING BOTH BOWING SEGMENTS AND SUPERCELL STRUCTURE WHERE LOW
   LEVEL WINDS VEER MORE WITH HEIGHT.
   
   AIR MASS W AND N OF THIS PRIMARY AREA OF TSTMS /NW HUT TO EAST
   CENTRAL NEB/ REMAINS MODERATELY UNSTABLE WITH STRONG EFFECTIVE BULK
   SHEAR VALUES SUPPORTIVE FOR ORGANIZED STORMS.  A FEW STORMS HAVE
   ALREADY DEVELOPED IN THIS ENVIRONMENT EITHER ALONG THE COLD FRONT
   EXTENDING NE-SW THROUGH THIS AREA OR ALONG OUTFLOW BOUNDARIES MOVING
   W/NW FROM PRIMARY REGION OF STRONGER ACTIVITY.  THUS...LOCAL
   EXTENSION IN AREA OF WW 290 MAY BECOME NECESSARY ACROSS NORTH
   CENTRAL KS INTO SERN NEB/WRN IA PRIOR TO EXPIRATION.
   
   ..PETERS.. 05/23/2007
   
   
   ATTN...WFO...DMX...EAX...OAX...TOP...ICT...GID...DDC...
   
   37009784 37229840 37779859 38449893 39149904 39879822
   41079717 41639642 41279523 40959485 39889481 37709738