Special Weather Statement, NWS Nashville, TN

Area Forecast Discussion
National Weather Service Nashville TN
246 AM CDT Sat Mar 27 2021

.DISCUSSION...

Some convection just now beginning to fire across nrn AL and nrn MS.
This is in response to a warm front which will be lifting northward
through the mid state today. Showers and thunderstorms will be
rapidly increasing over the next few hours with this activity
spreading northward and continuing into your Saturday.
Destabilization will be rather rapid with sfc based capes between
1000-1500 j-kg and LI values approaching -5C by 18Z. An examination
of upcoming lapse rates and mid level capes do support the
potential for some hail today, with perhaps the severe threshold
of 1 inch being surpassed. 850 mb wind speeds are not overly
impressive and the organized lift is somewhat sub-par. Helicities
are between 100-200, but the Hrrr does indicate a little
reflectivity wrapped signatures by afternoon. Overall looks like
some strong to severe storms with high winds and hail possible
with some cell rotation also possible. Storm direction looks like
from 250 deg at 40 mph or so.

Tonight, the slow approach of a strengthening frontal boundary will
provide well organized and strong forcing. However, phasing with the
better instability parameters is a little off with the instability
outrunning the forcing just a bit. Nevertheless, SPC has the entire
area in an enhanced risk. The threats will be damaging winds and
large hail but cannot rule out an isolated tornado or two. In
addition, flash flooding looks to be a big threat. For that reason,
the flash flood watch remains in effect. Latest storm total precip
shows 2-3 inches for most areas through tonight, with the bulk of
the heavy rainfall, of course, occurring overnight. localized 4 inch
amounts cannot be ruled out. Qpf gradients drop off rather markedly
to our north and south, but we are close enough to the event now
where we see the heavier rainfall is going to occur across our area.
Moving on, some shower activity will linger into your Sunday
morning. Clearing will commence in the afternoon.

For the near term temps, despite the clouds and rainfall, we will
see our temps warm into the lower 70s for today with humidities on
the upswing for sure. Cooler on Sunday and low temps will be in the
35 to 40 degree range by Monday morning.

In the ext fcst, a mid week frontal boundary will move through. The
feature looks weaker than our previous boundaries and instabilities
look marginal at best. Anyhow, shower chances return Tuesday and
Wednesday. It will be turning noticeably cooler on Wednesday and the
models are leaning toward slowly falling daytime temperatures.
Thursday and Friday are looking dry.

For our extended temps, it looks seasonal on Tuesday and then
turning colder Wednesday, as mentioned previously. Low temps for
Thursday through Saturday look like 30s.

Note that our growing season has begun and thus, the freeze warnings
and or frost advisories may begin to fly by late next week.

&&

.AVIATION...
06Z TAF DISCUSSION.

Poor flying conditions expected this TAF period as SHRA/TSRA
develop and affect all airports. No problems early this morning
with light winds and VFR conditions, but showers and storms will
rapidly develop and impact airports from 12Z onward with MVFR/IFR
conditions. Some improvement is possible this afternoon at
airports, before deteriorating again Saturday evening. Light
southeast winds early this morning will increase and become
southerly later today.

&&

.PRELIMINARY POINT TEMPS/POPS...
Nashville      73  57  63  38  66 /  80  90  60   0  10
Clarksville    73  52  60  35  63 /  30  90  20   0   0
Crossville     69  57  60  35  60 /  80  70  70   0  10
Columbia       75  59  64  37  66 /  80  80  60   0  10
Lawrenceburg   75  59  64  37  65 /  70  70  70   0  10
Waverly        73  53  62  36  64 /  50 100  30   0  10

&&

.OHX WATCHES/WARNINGS/ADVISORIES...
Flash Flood Watch from 7 AM CDT this morning through Sunday
evening for Bedford-Cannon-Cheatham-Clay-Coffee-Cumberland-
Davidson-De Kalb-Dickson-Fentress-Giles-Grundy-Hickman-Houston-
Humphreys-Jackson-Lawrence-Lewis-Macon-Marshall-Maury-Montgomery-
Overton-Perry-Pickett-Putnam-Robertson-Rutherford-Smith-Stewart-
Sumner-Trousdale-Van Buren-Warren-Wayne-White-Williamson-Wilson.

&&

DISCUSSION......21
AVIATION........Shamburger

Hazardous Weather Outlook...UPDATED
National Weather Service Nashville TN
711 PM CDT Fri Mar 26 2021

TNZ005>011-023>034-056>066-075-077>080-093>095-271000-
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-
711 PM CDT Fri Mar 26 2021

This Hazardous Weather Outlook is for Middle Tennessee.

.DAY ONE...Tonight.

Some strong to severe thunderstorms will be possible late tonight for
locations generally south of I-40 and around and west of I-24.
Large hail will be primary threat.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

Severe thunderstorms will be possible Saturday and Saturday night
across all of Middle Tennessee. Damaging winds, large hail, and
isolated tornadoes will all be possible. Multiple rounds of heavy
rainfall expected from mid morning hours on Saturday through at least
morning hours on Sunday. Rainfall amounts of 1 to 3 inches, with
locally higher amounts of 4 to 5 inches, expected on already
saturated ground conditions. Runoff impacts could last through
afternoon hours on Sunday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be needed. Please relay any
information about observed severe weather to the NWS while
following all local, state, and CDC guidelines.

Spotter Thunderstorm Reporting Criteria...
Tornado
Funnel Cloud
Flooding
Hail >= 1/2 Inch
Winds > 50 MPH (Measured)
Structural Damage
Trees or Power Lines Down

JB Wright

Special Weather Statement
National Weather Service Nashville TN
529 AM CDT Sat Mar 27 2021

TNZ006-025>028-059-271100-
Williamson TN-Dickson TN-Davidson TN-Wilson TN-Cheatham TN-
Montgomery TN-
529 AM CDT Sat Mar 27 2021

...SIGNIFICANT WEATHER ADVISORY FOR DAVIDSON...NORTHERN DICKSON...
SOUTHEASTERN MONTGOMERY...NORTHEASTERN WILLIAMSON...WEST CENTRAL
WILSON AND CHEATHAM COUNTIES UNTIL 600 AM CDT...

At 529 AM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from Charlotte to near Brentwood.
Movement was northeast at 40 mph.

Pea to half inch hail and winds in excess of 40 mph will be possible
with these storms.

Locations impacted include...
Franklin, Ashland City, Nashville, Brentwood, La Vergne, Mount
Juliet, Nolensville, Forest Hills, Oak Hill, White Bluff, Belle
Meade, Kingston Springs, Pegram, Hermitage, Rural Hill, Bellevue,
Antioch, Joelton, Pleasant View and Charlotte.

This includes the following highways...
 Interstate 40 between mile markers 185 and 225.
 Interstate 65 between mile markers 66 and 92.
 Interstate 24 between mile markers 40 and 63.

LAT...LON 3613 8641 3608 8648 3610 8652 3606 8653
      3608 8653 3608 8654 3606 8656 3604 8656
      3603 8659 3601 8661 3599 8662 3589 8677
      3621 8748 3648 8727
TIME...MOT...LOC 1029Z 230DEG 37KT 3619 8734 3596 8680

Shamburger

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NASHVILLE TN
533 AM CDT SAT MAR 27 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0518 AM     HAIL             8 N HOHENWALD           35.66N  87.54W
03/27/2021  E1.25 INCH       HICKMAN            TN   SOCIAL MEDIA

            TWITTER PHOTO OF HALF DOLLAR SIZE HAIL ON ARNOLD ROAD

&&

EVENT NUMBER OHX2100321

SHAMBURGER

Special Weather Statement
National Weather Service Nashville TN
552 AM CDT Sat Mar 27 2021

TNZ028-030-062>064-271130-
Cannon TN-Rutherford TN-Wilson TN-De Kalb TN-Smith TN-
552 AM CDT Sat Mar 27 2021

...SIGNIFICANT WEATHER ADVISORY FOR SOUTH CENTRAL SMITH...CENTRAL DE
KALB...SOUTHEASTERN RUTHERFORD...SOUTHEASTERN WILSON AND NORTHERN
CANNON COUNTIES UNTIL 630 AM CDT...

At 551 AM CDT, Doppler radar was tracking a strong thunderstorm 8
miles southeast of Murfreesboro, moving northeast at 50 mph.

Pea to half inch hail will be possible with this storm.

Locations impacted include...
Murfreesboro, Smithville, Woodbury, Gordonsville, Hickman,
Alexandria, Dowelltown, Liberty, Auburntown, Center Hill Lake, Edgar
Evans State Park, Milton and Readyville.

This includes the following highways...
 Interstate 40 between mile markers 257 and 258.
 Interstate 24 between mile markers 82 and 91.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 3601 8569 3568 8631 3578 8643 3620 8596
TIME...MOT...LOC 1051Z 229DEG 42KT 3577 8629

Shamburger

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NASHVILLE TN
602 AM CDT SAT MAR 27 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0558 AM     HAIL             7 N ASHLAND CITY        36.38N  87.06W
03/27/2021  E0.88 INCH       CHEATHAM           TN   TRAINED SPOTTER

&&

EVENT NUMBER OHX2100322

21

Special Weather Statement
National Weather Service Nashville TN
618 AM CDT Sat Mar 27 2021

TNZ007>010-028-029-271145-
Robertson TN-Wilson TN-Trousdale TN-Sumner TN-Clay TN-Macon TN-
618 AM CDT Sat Mar 27 2021

...SIGNIFICANT WEATHER ADVISORY FOR SUMNER...NORTH CENTRAL WILSON...
NORTHWESTERN CLAY...MACON...TROUSDALE AND NORTHEASTERN ROBERTSON
COUNTIES UNTIL 645 AM CDT...

At 618 AM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Springfield to Gallatin. Movement was
northeast at 45 mph.

Half inch hail will be possible with these storms.

Locations impacted include...
Gallatin, Springfield, Lafayette, Hartsville, White House,
Westmoreland, Cross Plains, Red Boiling Springs, Portland, Orlinda,
Mitchellville, Bethpage, Bugtussle, Oak Grove, Bledsoe Creek State
Park, Cottontown and Black Jack.

This includes Interstate 65 between mile markers 107 and 121.

LAT...LON 3665 8635 3662 8575 3660 8569 3629 8627
      3654 8696 3665 8684 3665 8659 3663 8656
      3665 8651
TIME...MOT...LOC 1118Z 229DEG 39KT 3654 8685 3635 8632

Shamburger

Special Weather Statement
National Weather Service Nashville TN
622 AM CDT Sat Mar 27 2021

TNZ030>033-064-271200-
Putnam TN-Overton TN-De Kalb TN-Jackson TN-Smith TN-
622 AM CDT Sat Mar 27 2021

...SIGNIFICANT WEATHER ADVISORY FOR WEST CENTRAL OVERTON...
SOUTHEASTERN SMITH...NORTHERN DE KALB...JACKSON AND NORTHWESTERN
PUTNAM COUNTIES UNTIL 700 AM CDT...

At 622 AM CDT, Doppler radar was tracking a strong thunderstorm near
Gordonsville, or 10 miles northwest of Smithville, moving northeast
at 35 mph.

Nickel size hail will be possible with this storm.

Locations impacted include...
Cookeville, Gainesboro, Algood, Baxter, Gordonsville, Hickman,
Alexandria, Dowelltown, Liberty, Whitleyville, Rickman, Center Hill
Lake, Granville, Edgar Evans State Park and Cummins Falls State Park.

This includes Interstate 40 between mile markers 257 and 282.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 3627 8535 3596 8590 3608 8606 3610 8606
      3648 8566
TIME...MOT...LOC 1122Z 230DEG 30KT 3608 8591

Shamburger