Special Weather Statement, NWS Nashville, TN

Area Forecast Discussion
National Weather Service Nashville TN
1226 PM CDT FRI JUL 8 2016

.UPDATE...
FOR 18Z AVIATION DISCUSSION.

&&

.DISCUSSION...

Regional satellite and radar images show thunderstorms and MCV
moving across western KY. A well defined outflow boundary was
dropping across our northwest counties. These features, along
with other subtle surface boundaries, will contribute to
thunderstorm development across the Mid State today.

The early morning upper air plot here at OHX showed very moist
and unstable conditions, including mixed layer capes already well
over 2,000 J/kg. As heating continues, those values will climb
into the 3,000-4,000 range. Thunderstorms will begin popping
before Noon and we could begin to see a few strong to severe
cells by 1pm. Damaging wind gusts will be the primary concern.

The influence of the MCV is expected to bring the greatest
coverage for storms and greatest severe threat to the northeast
quarter of our area, especially the Upper Cumberland. Enhanced
wind fields over this area will promote better thunderstorm
organization and potential for wet microbursts. So, pops have
been increased, especially from the Nashville area northeastward
to indicate "likely" thunderstorms this afternoon.

Another concern is the flash flooding potential. At this point we
do not have a watch posted. We are still unsure that the rain will
be concentrated over the area that have been hardest hit by rain
over recent days, which is our northern tier of counties, and
especially Stewart and Montgomery. Depending on how things set
up, we may need to revisit the idea of a FFA later today. This
issue may be of even more concern for tonight, when at least
scattered thunderstorms are expected to continue, and some areas
could experience an MCS with heavy rainfall. This weather pattern
continues to make it very difficult to forecast details of
convective development and evolution.

Otherwise for today, forecast is on track for steamy highs ranging
from the upper 80s to mid 90s, and heat index values in the lower
100s.

&&

.AVIATION...
18Z TAF DISCUSSION.

Scattered thunderstorms will develop through the afternoon,
mainly over the Cumberland Plateau region. Will include tempo
group for CSV. Less certainty for BNA, so will go with VCTS, and
no mention at all for CKV. Thunderstorms may be severe with gusty
winds. Otherwise, winds will be WSW around 10kt with a few gusts
around 18kt. Lots of uncertainty tonight, so not including much
other than some patchy BR, but models indicate another MCS is
possible overnight. Will wait to include overnight storms when we
are more confident.

&&

.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

DISCUSSION......13
AVIATION........13

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NASHVILLE TN
1200 PM CDT FRI JUL 8 2016

TNZ005>011-023>034-056>066-075-077>080-093>095-091700-
STEWART-MONTGOMERY-ROBERTSON-SUMNER-MACON-CLAY-PICKETT-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-
1200 PM CDT FRI JUL 8 2016

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF MIDDLE
TENNESSEE.

.DAY ONE...THIS AFTERNOON AND TONIGHT

STRONG TO SEVERE THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND
TONIGHT ACROSS MIDDLE TENNESSEE. THE GREATEST SEVERE POTENTIAL IS
EXPECTED ACROSS THE UPPER CUMBERLAND REGION THIS AFTERNOON. THE
MAIN THREATS WILL BE DAMAGING STRAIGHT LINE WINDS AND HEAVY
RAINS...WHICH COULD LEAD TO LOCALIZED FLASH FLOODING.

HEAT INDICES ARE EXPECTED TO CLIMB INTO THE LOW 100'S THIS
AFTERNOON FOR MANY LOCATIONS WEST OF THE CUMBERLAND PLATEAU.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

A WARM AND HUMID PATTERN WILL CONTINUE WITH A CHANCE FOR ISOLATED
TO SCATTERED THUNDERSTORMS EACH DAY...SATURDAY THROUGH THURSDAY.
ALTHOUGH WIDESPREAD HAZARDOUS WEATHER IS NOT EXPECTED...A FEW
THUNDERSTORMS COULD BE STRONG TO SEVERE...MAINLY DURING THE
AFTERNOON AND EVENING HOURS. GUSTY WINDS AND HEAVY DOWNPOURS WILL
THE MAIN CONCERNS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON AND EVENING.

13

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
101 PM CDT FRI JUL 8 2016

TNZ030>033-081845-
OVERTON TN-SMITH TN-PUTNAM TN-JACKSON TN-
101 PM CDT FRI JUL 8 2016

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN SMITH...NORTHWESTERN
PUTNAM...SOUTHWESTERN OVERTON AND SOUTHERN JACKSON COUNTIES UNTIL 145
PM CDT...

AT 101 PM CDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM 7
MILES NORTHWEST OF BAXTER...OR 10 MILES SOUTHWEST OF GAINESBORO...
MOVING EAST AT 25 MPH.

WINDS IN EXCESS OF 30 MPH WILL BE POSSIBLE WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
COOKEVILLE...ALGOOD...BAXTER AND GRANVILLE.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 800 PM CDT FOR
MIDDLE TENNESSEE.

LAT...LON 3633 8542 3621 8537 3609 8542 3611 8579
      3613 8581 3612 8583 3613 8583 3630 8584
TIME...MOT...LOC 1801Z 269DEG 22KT 3622 8574

MR3