[BNAWX] Severe Storm Outlook Narrative

[EMWIN Server]

ACUS11 KWNS 181554
SWOMCD
SPC MCD 181553
KYZ000-TNZ000-181730-

MESOSCALE DISCUSSION 0119
NWS STORM PREDICTION CENTER NORMAN OK
0953 AM CST WED FEB 18 2009

AREAS AFFECTED...PORTIONS OF WRN AND CNTRL KY INTO MIDDLE TN

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 181553Z - 181730Z

THE THREAT FOR ORGANIZED...SEVERE STORMS APPEARS TO BE INCREASING
ACROSS THE DISCUSSION AREA AND CONVECTIVE TRENDS ARE BEING MONITORED
FOR A WW.

VISIBLE SATELLITE AND RADAR DATA INDICATE DEEPENING CUMULUS/TSTM
DEVELOPMENT OCCURRING IN SHORT WSW-ENE ORIENTED BANDS OVER WRN KY
INTO NWRN TN AS OF 1540Z.  THIS ACTIVITY IS OCCURRING AHEAD OF
SURFACE COLD FRONT WITHIN A ZONE OF FAIRLY RAPID BOUNDARY LAYER
WARMING/MOISTENING PER 3-HR CHANGE FIELDS.  MOREOVER...WATER VAPOR
IMAGERY SUGGESTS THAT THIS AREA IS ALONG THE SRN FRINGE OF A BAND OF
ASCENT ASSOCIATED WITH A VIGOROUS SHORT WAVE TROUGH CURRENTLY MOVING
THROUGH IL/IND.

BASED ON 12Z LIT SOUNDING...ENVIRONMENT IS ALREADY UNCAPPED WITH
MLCAPE OF 500-700 J/KG.  CONTINUED HEATING/MOISTENING IN ADVANCE OF
COLD FRONT SHOULD SUPPORT FURTHER AIR MASS DESTABILIZATION TODAY
WITH MLCAPE APPROACHING 1000 J/KG.  VERTICAL SHEAR IS QUITE STRONG
/EFFECTIVE BULK SHEAR OF AROUND 70 KT/ WITH GENERALLY
LONG...STRAIGHT HODOGRAPHS.  AS SUCH...ENVIRONMENT WILL BE
SUPPORTIVE OF SPLITTING SUPERCELLS CAPABLE OF DAMAGING WINDS AND
HAIL.  A TORNADO OR TWO WILL BE POSSIBLE WITH ANY MORE INTENSE
CYCLONIC UPDRAFTS.  AS SUCH...1630Z OUTLOOK WILL BE EXPANDED FARTHER
NWD IN KY AND A WW MAY BE NECESSARY.

..MEAD.. 02/18/2009

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

ATTN...WFO...MRX...JKL...LMK...OHX...PAH...

LAT...LON   36848737 37358619 37658524 37718476 37288466 36598478
            36028513 35818568 35758649 36168741 36848737



This weather bulletin was brought to you by:
www.nashvilleweather.net