ZCZC SPCSWOMCD ALL
ACUS11 KWNS 140038 
SPC MCD 140038 
TNZ000-KYZ000-140215-

MESOSCALE DISCUSSION 1401
NWS STORM PREDICTION CENTER NORMAN OK
0738 PM CDT MON JUL 13 2015

AREAS AFFECTED...PORTIONS OF MIDDLE/ERN TN

CONCERNING...SEVERE THUNDERSTORM WATCH 415...

VALID 140038Z - 140215Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 415
CONTINUES.

SUMMARY...THE SEVERE THREAT ACROSS WW 415 CONTINUES PRIMARILY WITH A
SUPERCELL PROGRESSING THROUGH CLAY COUNTY TN. WHILE NEW THUNDERSTORM
DEVELOPMENT IS POSSIBLE ELSEWHERE...THE POTENTIAL FOR SEVERE
CONVECTION AWAY FROM THIS SUPERCELL APPEARS TO BE WANING.

DISCUSSION...A ROBUST SUPERCELL /PREVIOUSLY INITIATED ALONG TRAILING
OUTFLOW IN KY FROM THE SEWD-PROGRESSING MCS/ IS GENERALLY
MAINTAINING INTENSITY AS IT TRACKS SWD INTO TN THIS EVENING.
INDEED...THE CELL HAS EXHIBITED NUMEROUS SIGNALS OF A
WELL-ORGANIZED/ROTATING UPDRAFT...INCLUDING PULSING ZDR
COLUMNS...DEPRESSED CC IN THE HAIL-GROWTH ZONE...AND OCCASIONAL ZDR
ARC SIGNATURES /SUGGESTIVE OF VIGOROUS SIZE SORTING OF DROPS/. 

ALTHOUGH LOW-LEVEL FLOW IS MODEST AT BEST...WELL-DEFINED VEERING
WITH HEIGHT AND THE PRESENCE OF 40-55 KTS OF MID-LEVEL FLOW
/OBSERVED IN THE 00Z BNA RAOB/ IS YIELDING 40-45 KTS OF EFFECTIVE
SHEAR. THEREFORE...UPDRAFT ROTATION/ORGANIZATION WITH THIS SUPERCELL
SHOULD FURTHER ENCOURAGE LARGE HAIL GROWTH AS IT PROGRESSES S/SE
OVER THE NEXT COUPLE OF HOURS. ELSEWHERE...NEW INITIATION APPEARS
QUESTIONABLE AS INSOLATION WANES AND STRONGER FORCING FOR ASCENT
REMAINS FARTHER NORTH. THEREFORE...NEW WATCH ISSUANCE IS NOT
ANTICIPATED THIS EVENING.

..PICCA.. 07/14/2015

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...MRX...LMK...OHX...

LAT...LON   36638577 36598479 35388460 35098512 35218575 36638577 

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