Severe Thunderstorm Warning 277, NWS Nashville, TN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
1105 AM CDT THU AUG 5 2010

.UPDATE...
COLD FRONT...JUST EAST OF PADUCAH...WILL HEAD SOUTHEAST AND
UNDERCUT VERY MOIST AND HOT UNSTABLE AIR MASS IN THE MID STATE
THIS AFTERNOON. DEW POINT TONGUE OF 77 DEGS CURRENTLY IN OUR
NORTHWESTERN COUNTIES...AND TEMPERATURES IN THE LOWER
90S...ALREADY PRODUCING HEAT INDICES IN THE 101 TO 104 DEGREE
RANGE.

12Z BNA SOUNDING, MODIFIED TO A MAX TEMPERATURE OF 97 DEGREES,
PROVIDES THE FOLLOWING INSTABILITY STATS:

TOTAL TOTALS 47
LI -7
CAPE 4.2K J/KG
EL 51.4 K FT

WRF AND RUC INDICATE SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS BREAKING OUT DURING THE AFTERNOON OVER A GOOD CHUNK
OF THE MID STATE, AND LATEST MET RAISES POPS AT CSV TO 80%. THUS,
WILL GO WITH "LIKELY POPS" FOR MUCH OF OUR CWA, SOUTHEAST OF A
SPRINGFIELD TO CAMDEN LINE (INCLUDING BNA AND CSV).

BELIEVE OLD OUTFLOW BOUNDARY, JUST NORTH AND WEST OF DAVIDSON
COUNTY, WILL ALSO PROVIDE A FOCUS FOR AFTERNOON TSTM DEVELOPMENT.

&&

.OHX WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR TNZ007>011-026>033-
059>065-075-077-078.

EXCESSIVE HEAT WARNING UNTIL 7 PM CDT THIS EVENING FOR TNZ005-
006-022>025-056>058-093>095.

&&

19

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NASHVILLE TN
532 AM CDT THU AUG 5 2010

TNZ005>011-022>034-056>066-075-077>080-093>095-061030-
STEWART-MONTGOMERY-ROBERTSON-SUMNER-MACON-CLAY-PICKETT-BENTON-
HOUSTON-HUMPHREYS-DICKSON-CHEATHAM-DAVIDSON-WILSON-TROUSDALE-
SMITH-JACKSON-PUTNAM-OVERTON-FENTRESS-PERRY-HICKMAN-LEWIS-
WILLIAMSON-MAURY-MARSHALL-RUTHERFORD-CANNON-DE KALB-WHITE-
CUMBERLAND-BEDFORD-COFFEE-WARREN-GRUNDY-VAN BUREN-WAYNE-LAWRENCE-
GILES-
532 AM CDT THU AUG 5 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR MIDDLE TENNESSEE.

.DAY ONE...TODAY AND TONIGHT...

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS MIDDLE
TENNESSEE TODAY AND TONIGHT. A FRONTAL BOUNDARY WILL PUSH INTO THE
AREA...WITH DAMAGING WINDS AND LOCALLY HEAVY RAINFALL POSSIBLE.

HEAT INDEX VALUES ARE EXPECTED TO REACH 110 DEGREES ACROSS THE
WESTERN THIRD OF MIDDLE TENNESSEE THROUGH 7 PM TODAY...WITH AN
EXCESSIVE HEAT WARNING IN EFFECT. HEAT INDEX VALUES OF 104 AND 107
DEGREES ARE EXPECTED ACROSS MOST OF CENTRAL AND EASTERN MIDDLE
TENNESSEE COUNTIES THROUGH 7 PM TODAY...WITH A HEAT ADVISORY IN
EFFECT.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY...

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER CALL TO ACTION STATEMENT...

REPORTS FROM TRAINED WEATHER SPOTTERS MAY BE NEEDED.

SPOTTER THUNDERSTORM REPORTING CRITERIA...
TORNADO
FUNNEL CLOUD
FLOODING
HAIL >= 1/2 INCH
WINDS > 50 MPH (MEASURED)
STRUCTURAL DAMAGE
TREES OR POWER LINES DOWN

04