MESOSCALE DISCUSSION 0549
   NWS STORM PREDICTION CENTER NORMAN OK
   0345 PM CDT FRI MAY 08 2015

   AREAS AFFECTED...SOUTHWEST/SOUTH-CENTRAL OK AND WESTERN NORTH TX

   CONCERNING...TORNADO WATCH 143...

   VALID 082045Z - 082215Z

   THE SEVERE WEATHER THREAT FOR TORNADO WATCH 143 CONTINUES.

   SUMMARY...THE TORNADO RISK IS STEADILY INCREASING ACROSS THE WESTERN
   PART OF NORTH TX AND SOUTHWEST OK...PARTICULARLY IN AREAS ROUGHLY 40
   MILES EITHER SIDE OF THE RED RIVER...WHILE OTHER SEVERE
   THUNDERSTORMS WILL BE POSSIBLE EAST-NORTHEASTWARD INTO EAST-CENTRAL
   OK. TORNADO WATCH 143 CONTINUES UNTIL 02Z.

   DISCUSSION...IN VICINITY OF A SOUTHWEST-NORTHEASTWARD ORIENTED
   FRONTAL ZONE AND NEARBY CORRIDOR OF MODIFYING OUTFLOW...SUPERCELLS
   HAVE INTENSIFIED OVER THE PAST 1-2 HOURS ACROSS SOUTHWEST OK AND THE
   WESTERN PART OF NORTH TX AMID A VERY MOIST/MODERATELY UNSTABLE
   ENVIRONMENT. LARGE HAIL WILL REMAIN A DISTINCT CONCERN...AND THE
   TORNADO THREAT APPEARS TO HAVE INCREASED VIA RESIDUAL OUTFLOW
   INFLUENCE AND BACKING/STRENGTHENING LOW-LEVEL EAST-SOUTHEASTERLY
   WINDS ACROSS THE WESTERN PART OF NORTH TX/IMMEDIATE RED RIVER
   VICINITY. THE FREDERICK WSR-88D VWP SUPPORTS AT LEAST 150-200 M2/S2
   OF 0-1 KM SRH. 

   FARTHER NORTH...WHILE CLOUD COVER HAS BEEN SLOW TO ABATE ACROSS
   PARTS OF OK...STRONG/POTENTIALLY SEVERE THUNDERSTORMS WILL ALSO
   CONTINUE TO SPREAD NORTHEASTWARD TOWARD CENTRAL/SOUTH-CENTRAL OK IN
   VICINITY OF SURFACE FRONTAL ZONE AND SUBSEQUENT/REINFORCING OUTFLOW.

   ..GUYER.. 05/08/2015


   ATTN...WFO...FWD...OUN...LUB...

   LAT...LON   34380006 35279918 35699736 34419677 33239820 33639982
               34380006