MESOSCALE DISCUSSION 0218
   NWS STORM PREDICTION CENTER NORMAN OK
   0542 PM CDT MON MAR 09 2009
   
   AREAS AFFECTED...N CNTRL/NE OK THROUGH ERN KS/WRN MO
   
   CONCERNING...TORNADO WATCH 52...
   
   VALID 092242Z - 100015Z
   
   THE SEVERE WEATHER THREAT FOR TORNADO WATCH 52 CONTINUES.
   
   SEVERE THREAT APPEARS TO BE INCREASING.  IT IS NOT YET CERTAIN THAT
   ADDITIONAL WWS WILL BE NEEDED TO THE NORTH/EAST...BUT TRENDS WILL BE
   MONITORED FOR THIS POSSIBILITY.
   
   INCREASING STORM DEVELOPMENT IS NOW UNDERWAY...ALONG THE WESTERN
   MOISTURE GRADIENT OF THE SOUTHERLY RETURN FLOW OFF THE GULF OF
   MEXICO.  THIS IS OCCURRING IN RESPONSE TO STRONG LOW-LEVEL WARM
   ADVECTION...ALONG/NORTH OF A SURFACE WARM FRONT NEAR THE
   KANSAS/OKLAHOMA BORDER...WHICH IS EXPECTED TO SLOWLY ADVANCE
   NORTHWARD THROUGH SOUTHERN KANSAS/SOUTHWEST MISSOURI BETWEEN NOW AND
   02-03Z.  THE BOUNDARY LAYER NEAR THE IMMEDIATE VICINITY OF THE WARM
   FRONT IS DESTABILIZING...WITH MIXED LAYER CAPE INCREASING IN EXCESS
   OF 500 J/KG.  AND...STORMS TAKING ROOT WITHIN THE BOUNDARY LAYER
   ALONG THE WARM FRONT...WILL POSSESS POTENTIAL TO TRACK ALONG IT...IN
   THE PRESENCE OF STRONG SOUTHWESTERLY DEEP LAYER SHEAR AND
   STRENGTHENING CLOCKWISE CURVED LOW-LEVEL HODOGRAPHS.  30-40 KT
   SOUTHERLY 850 FLOW IS PROGGED TO INCREASE IN EXCESS OF 50 KTS BY
   EARLY EVENING...WHICH WILL CONTRIBUTE TO TORNADIC POTENTIAL IN
   EVOLVING SUPERCELLS.  
   
   STORMS REMAINING ROOTED IN THE ELEVATED WARM ADVECTION REGIME TO THE
   NORTH OF THE FRONT WILL TEND TO BE ADVECTED RAPIDLY NORTHEASTWARD IN
   THE PRESENCE OF 50-60 KT DEEP LAYER SOUTHWESTERLY MEAN FLOW.  SHEAR
   FOR THESE STORMS STILL SEEMS STRONG ENOUGH TO SUPPORT THE RISK FOR
   AT LEAST MARGINALLY SEVERE HAIL...DESPITE SOMEWHAT WEAK MID-LEVEL
   LAPSE RATES.  SOME OF THIS ACTIVITY MAY SPREAD NORTH/NORTHEAST OF
   THE WATCH...INTO AREAS NEAR/SOUTH AND EAST OF KANSAS CITY EARLY THIS
   EVENING.
   
   ..KERR.. 03/09/2009
   
   
   ATTN...WFO...SGF...EAX...TSA...TOP...ICT...OUN...
   
   LAT...LON   37039773 37979705 38669610 39229546 39039331 37549393
               36779530 37039773