MESOSCALE DISCUSSION 1883
   NWS STORM PREDICTION CENTER NORMAN OK
   0733 PM CDT MON OCT 13 2014

   AREAS AFFECTED...CNTRL AND NRN AL / SRN MIDDLE TN

   CONCERNING...TORNADO WATCH 540...

   VALID 140033Z - 140130Z

   THE SEVERE WEATHER THREAT FOR TORNADO WATCH 540 CONTINUES.

   SUMMARY...THE THREAT FOR DMGG WIND GUSTS WILL BE THE PREDOMINATE
   SEVERE THREAT GOING FORWARD IN TIME THIS EVENING.  A TORNADO OR TWO
   REMAINS POSSIBLE...ESPECIALLY WITH ANY STRONGER AND LONGER-LIVED
   MESOVORTICES WITHIN THE QLCS.  SUPERCELL TORNADO POTENTIAL WILL
   PROBABLY BE LOW BUT IT HAS NOT DIMINISHED ENTIRELY.

   DISCUSSION...0030Z RADAR IMAGERY SHOWS A MATURE QLCS NEAR THE MS/AL
   BORDER EXTENDING NWD INTO MIDDLE TN.  THE WARM/MOIST SECTOR HAS
   LARGELY OVERSPREAD MUCH OF NRN AL EXCEPT FOR FAR NERN AL WHERE A
   DIFFUSE AND NEARLY STATIONARY MARITIME FRONT HAS LIMITED DEWPOINTS
   FROM RISING INTO THE MID-UPPER 60S UNTIL RECENTLY.  THE 14/00Z BMX
   RAOB SHOW A VERY MOIST TROPOSPHERIC PROFILE AMIDST A LOW-LEVEL
   VEERING AND STRENGTHENING FLOW FIELD WITH HEIGHT.  A MODERATELY
   BUOYANT AIRMASS FEATURING AROUND 1100 J/KG MLCAPE AND 400 M2/S2
   EFFECTIVE SRH WILL SUPPORT THE POTENTIAL FOR UPDRAFTS TO ACQUIRE
   ROTATION BOTH IN THE QLCS AND PERHAPS WITH A STRONGER QUASI-DISCRETE
   STORM AHEAD OF THE LINE.  SPORADIC WIND DAMAGE ASSOCIATED WITH
   DOWNWARD MOMENTUM TRANSPORT IN THE QLCS WILL LIKELY BE THE
   PREDOMINATE THREAT THIS EVENING AS THE QLCS MOVES ACROSS THE TN
   VALLEY.  A BRIEF/WEAK MESOVORTEX TORNADO IS POSSIBLE BUT THE DEEPLY
   MERIDIONAL FLOW FROM THE SURFACE THROUGH H5 MAY TEND TO LIMIT A MORE
   WIDESPREAD DMGG WIND EPISODE AND TORNADO POTENTIAL TO A DEGREE.

   ..SMITH.. 10/14/2014


   ATTN...WFO...MRX...OHX...BMX...HUN...

   LAT...LON   35048772 35788725 35768617 35538580 35048573 34028618
               33198669 33128745 33288784 33468800 35048772