MESOSCALE DISCUSSION 0276
   NWS STORM PREDICTION CENTER NORMAN OK
   1244 PM CDT MON MAR 18 2013
   
   AREAS AFFECTED...TN...NRN AL...NRN MS...FAR ERN AR
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 51...
   
   VALID 181744Z - 181915Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 51
   CONTINUES.
   
   SUMMARY...A SEVERE THREAT WILL LIKELY CONTINUE THIS AFTERNOON ACROSS
   MIDDLE TN...NRN MS AND NRN AL. WIND DAMAGE SHOULD BE THE PRIMARY
   THREAT BUT HAIL AND A MARGINAL TORNADO THREAT WILL ALSO BE POSSIBLE
   WITH THE STRONGER THUNDERSTORMS.
   
   DISCUSSION...THE LATEST SFC ANALYSIS SHOWS A COLD FRONT MOVING EWD
   ACROSS THE CENTER OF WW 51 WITH A MOIST AXIS FROM ERN MS NEWD INTO
   MIDDLE TN. SEVERAL STRONG TO SEVERE THUNDERSTORMS ARE ONGOING ALONG
   THE MOIST AXIS WHERE SFC DEWPOINTS ARE IN THE 55 TO 60 F RANGE. SFC
   TEMPS HAVE BEEN SLOW TO WARM THIS MORNING AND INSTABILITY IS STILL
   WEAK ACROSS THE WATCH AREA. IN SPITE OF THE WEAK INSTABILITY...A 40
   TO 55 KT LOW-LEVEL JET IS LOCATED FROM NERN MS EXTENDING NEWD INTO
   MIDDLE TN. THIS FEATURE IS ENHANCING LIFT AND IS PROVIDING STRONG
   DEEP LAYER SHEAR SUFFICIENT FOR A SEVERE THREAT. THE LATEST WSR-88D
   VWP AT HUNTSVILLE AL SHOWS 60 KT OF 0-6 KM SHEAR WHICH SHOULD ENABLE
   STORMS TO REMAIN SOMEWHAT ORGANIZED. IN ADDITION...45 KT OF FLOW
   EXISTS AT 1 KM SUGGESTING THE ENVIRONMENT WILL SUPPORT A THREAT FOR
   WIND DAMAGE. THE FASTER MOVING LINE-SEGMENTS SHOULD HAVE THE
   GREATEST WIND DAMAGE THREAT. HAIL AND A MARGINAL TORNADO THREAT MAY
   ALSO BE POSSIBLE WITH STORMS THAT EXHIBIT ROTATION.
   
   ..BROYLES/HART.. 03/18/2013
   
   
   ATTN...WFO...MRX...JKL...FFC...LMK...OHX...BMX...HUN...MEG...
   JAN...
   
   LAT...LON   36768534 35618687 34988847 34778911 34288992 33779038
               33448992 33318711 34038551 35638437 36638403 36768534