MESOSCALE DISCUSSION 0658
   NWS STORM PREDICTION CENTER NORMAN OK
   0348 PM CDT FRI MAY 01 2009
   
   AREAS AFFECTED...SOUTHERN MIDDLE TN INTO NORTHERN AL/NORTHEAST MS
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 221...
   
   VALID 012048Z - 012215Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 221
   CONTINUES.
   
   SEVERE TSTM WATCH 221 CONTINUES UNTIL 00Z ACROSS MIDDLE TN AND
   NORTHERN AL/NORTHEAST MS.
   
   SEVERE QUASI-LINEAR MCS CONTINUES TO ORGANIZE/ADVANCE SOUTHEASTWARD
   ALONG THE MIDDLE TN/NORTHERN AL BORDER AS OF 2045Z. AHEAD OF THIS
   MCS...THE BOUNDARY LAYER CONTINUES TO WARM/QUICKLY RECOVER ACROSS
   NORTHERN AL FROM THE SOUTHWEST ON THE PERIPHERY OF A RESIDUAL
   MESO-HIGH/CONVECTIVE OUTFLOW ACROSS NORTHEAST AL/EASTERN TN. GIVEN A
   RICH VORTICITY/HEIGHTENED SRH ENVIRONMENT WITH BACKED LOW LEVEL FLOW
   ALONG THE MODIFYING OUTFLOW BOUNDARY FROM SOUTH MIDDLE TN INTO
   NORTHEAST AL...A QLCS-EMBEDDED TORNADO RISK CANNOT BE RULED OUT. BUT
   OTHERWISE DAMAGING WINDS/SEVERE HAIL /ALONG WITH HEAVY RAINFALL/
   SHOULD REMAIN THE PRIMARY THREATS AS THE MCS CONTINUES TO GROW
   UPSCALE OVER THE NEXT FEW HOURS.
   
   ..GUYER.. 05/01/2009
   
   
   ATTN...WFO...FFC...OHX...BMX...HUN...MEG...
   
   LAT...LON   35598837 35488686 34488542 33778596 33738732 34468836
               35598837