MESOSCALE DISCUSSION 0453
   NWS STORM PREDICTION CENTER NORMAN OK
   0440 PM CDT FRI APR 23 2004
   
   AREAS AFFECTED...NORTHWEST TX AND SRN OK
   
   CONCERNING...TORNADO WATCH 109...
   
   VALID 232140Z - 232245Z
   
   NEW WW WILL BE NEEDED BY 23Z FOR PORTIONS OF WRN/NRN TX AND INTO
   SOUTH CENTRAL OK.
   
   LINE OF SUPERCELLS EXTENDS 20 E FSI TO 30 NW ABI. THE STORMS FROM SW
   OF SPS TO NORTH OF ABI HAVE RECENTLY MERGED OUTFLOW BOUNDARIES AND
   MAY BECOME MORE OF A WIND THREAT. HOWEVER...TORNADOES REMAIN
   POSSIBLE IN THE STORMS THAT CAN MAINTAIN A CELLULAR STRUCTURE.
   ALTHOUGH THE LOW LEVEL SHEAR IS NOT PARTICULARLY STRONG...THE
   HORIZONTAL VORTICITY ALONG THE SW-NE ORIENTED COLD FRONT MAY BE
   SUPPORTIVE OF TORNADOES ALONG THE BOUNDARY IN SRN OK AND THE
   BOUNDARY IN WRN TX. THE STRONG DEEP LAYER SHEAR...MUCAPE VALUES
   AROUND 2000 J/KG...AND STEEP LAPSE RATES SUGGESTS THE MAIN SEVERE
   WEATHER THREAT WILL BE VERY LARGE HAIL AND OCCASIONAL DAMAGING
   WINDS.
   
   ..IMY.. 04/23/2004
   
   
   ATTN...WFO...FWD...OUN...SJT...LUB...MAF...
   
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