MESOSCALE DISCUSSION 0320
   NWS STORM PREDICTION CENTER NORMAN OK
   0159 PM CDT THU MAR 22 2007
   
   AREAS AFFECTED...PARTS OF NRN OK THRU SRN KS
   
   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 
   
   VALID 221859Z - 222100Z
   
   LATEST OBJECTIVE SURFACE ANALYSIS INDICATES THAT BREAKS IN OVERCAST
   ARE ALLOWING FOR POCKETS OF WEAK TO MODERATE BOUNDARY LAYER
   DESTABILIZATION...TO THE SOUTH OF A SURFACE FRONT WHICH HAS STALLED
   ACROSS THE TEXAS/OKLAHOMA PANHANDLE REGION THROUGH SOUTHERN KANSAS. 
   THIS IS ON THE NORTHERN PERIPHERY OF MID-LEVEL SUBTROPICAL RIDGING
   ACROSS THE SOUTHERN PLAINS.  HOWEVER... MODEL/OBSERVATIONAL DATA
   INDICATE THAT A WEAK IMPULSE...ASSOCIATED WITH A JET STREAK
   EMANATING FROM THE UPSTREAM SOUTHERN BRANCH TROUGH...IS PROGRESSING
   INTO THE CREST OF THIS RIDGE.  AND...ASSOCIATED LARGE-SCALE ASCENT
   IS CONTRIBUTING TO WEAKENING INHIBITION.  NEW CONVECTIVE DEVELOPMENT
   IS ALREADY UNDERWAY ACROSS THE EASTERN TEXAS PANHANDLE INTO WESTERN
   OKLAHOMA...AND ADDITIONAL VIGOROUS ACTIVITY APPEARS POSSIBLE INTO
   THE WICHITA AREA OF SOUTHERN KANSAS BY 20-21Z...WHERE MIXED LAYER
   CAPE MAY EXCEED 1500 J/KG LATE THIS AFTERNOON.  LOW-LEVEL FLOW
   FIELDS ARE NOT PARTICULARLY STRONG...BUT WITH THE APPROACH OF A 50+
   KT 500 MB JET SPEED MAXIMUM...VERTICAL SHEAR SEEMS LIKELY TO BECOME
   INCREASING SUPPORTIVE OF UPDRAFT ROTATION.
   
   SUPERCELLS APPEAR POSSIBLE NEAR FRONTAL ZONE LATE THIS
   AFTERNOON...WITH ASSOCIATED ENHANCED SEVERE THREATS.  THREAT BEYOND
   AN ISOLATED SUPERCELL OR TWO IS STILL A BIT UNCERTAIN...BUT TRENDS
   WILL CONTINUE TO BE CLOSELY MONITORED FOR THE POSSIBILITY OF A WW.
   
   ..KERR.. 03/22/2007
   
   
   ATTN...WFO...SGF...TSA...ICT...OUN...DDC...AMA...
   
   35810038 36340009 37189899 37709815 37969725 38019566
   37719499 36729514 36639705 35069936 34950076