MESOSCALE DISCUSSION 0729
   NWS STORM PREDICTION CENTER NORMAN OK
   1214 PM CDT SUN MAY 04 2003
   
   AREAS AFFECTED...SE NE...SW IA...NW MO
   
   CONCERNING...SEVERE THUNDERSTORM POTENTIAL 
   
   VALID 041714Z - 041915Z
   
   THREAT FOR LONG LIVED SUPERCELLS WITH POSSIBLE STRONG TORNADOES IS
   INCREASING ACROSS THE LOWER/MID MISSOURI VALLEY.
   
   RAPID INTENSE CONVECTIVE DEVELOPMENT IS ONGOING ON NOSE OF DRY
   SLOT...NORTH OF SURFACE SURFACE LOW WHICH CONTINUES TO SLOWLY DEEPEN
   SOUTH OF HASTINGS NEB.	STRONGER 2 HOUR SURFACE PRESSURE FALLS ARE
   BECOMING FOCUSED NORTHEAST OF SURFACE LOW ACROSS SOUTHEAST
   NEBRASKA...AND SOUTHWARD AHEAD OF DRY LINE INTO NORTHEAST KANSAS. 
   BY 21Z SURFACE LOW APPEARS LIKELY TO MIGRATE TOWARD THE BEATRICE NEB
   AREA...WITH DRY LINE CURVING SOUTHWARD INTO THE VICINITY OF TOPEKA
   KS.  STRONGLY DIFLUENT AND DIVERGENT UPPER FLOW FIELD WILL AID RAPID
   DEVELOPMENT OF SUPERCELLS DURING THE NEXT COUPLE OF HOURS ACROSS
   SOUTHEAST NEBRASKA AND NORTHEAST KANSAS...WHICH WILL DEVELOP
   NORTHEASTWARD INTO PARTS OF SOUTHWEST IOWA/NORTHWEST MISSOURI BY
   LATE AFTERNOON.
   
   LOW-LEVEL INVERSION LAYER ON COOL SIDE OF SURFACE WARM FRONT IS
   EXPECTED TO RAPIDLY WEAKEN THROUGH THE MID AFTERNOON...WITH FURTHER
   SURFACE HEATING AND CONTINUED LOW-LEVEL FORCING FOR UPWARD VERTICAL
   MOTION ASSOCIATED WITH APPROACHING SURFACE LOW CENTER.	BACK FLOW
   JUST AHEAD OF THIS LOW WILL ENHANCE LOW-LEVEL HODOGRAPH CURVATURE
   BENEATH STRONG SOUTHERLY LOW-LEVEL JET AND STRONG WEST SOUTHWESTERLY
   MID/UPPER JET...AND WILL CONTRIBUTE TO POTENTIAL FOR ISOLATED STRONG
   TORNADOES AS LOW-LEVEL THERMODYNAMIC ENVIRONMENT BECOMES
   INCREASINGLY FAVORABLE.
   
   ..KERR.. 05/04/2003
   
   
   ATTN...WFO...DMX...EAX...OAX...TOP...
   
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