Alert archive / Tennessee / Tornado Warnings in 2021

Tornado Warning 5, NWS Huntsville, AL

April 8, 2021Franklin County, Tennessee

NWS Huntsville, AL issued this tornado warning at Apr 8, 2021, 9:37 AM CDT for Franklin County, Tennessee. It was in force for 8 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Apr 8, 2021, 9:37 AM CDT (14:37 UTC)
Expired
Apr 8, 2021, 9:45 AM CDT
In force
8 min
Issued by
NWS Huntsville, AL
Area
Storm-based polygon
Tornado
Radar indicated

County Franklin County, TN

The radar

The Northeast Alabama radar (KHTX), 45 km from the middle of the area, began a volume at 14:38 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 12:00Z, 2.6 hours before the alert went out and 99 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Nashville Metro, TN at 12:00Z on 2021-04-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 55 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Nashville Metro, TN at 12:00Z on 2021-04-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 354 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
55 J/kg
Mixed-layer CIN
-72 J/kg
Mixed-layer LCL
626 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
354 m²/s²
0-3 km storm-relative helicity
375 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

As transmitted.

558 
WFUS54 KHUN 081437
TORHUN
TNC051-081445-
/O.NEW.KHUN.TO.W.0005.210408T1437Z-210408T1445Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Huntsville AL
937 AM CDT Thu Apr 8 2021

The National Weather Service in Huntsville Alabama has issued a

* Tornado Warning for...
  North central Franklin County in Middle Tennessee...

* Until 945 AM CDT.
    
* At 937 AM CDT, a severe thunderstorm capable of producing a tornado
  was located near Estill Springs, or 8 miles north of Winchester,
  moving northeast at 30 mph.

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* Locations impacted include...
  Estill Springs, Woods Reservoir and Arnold AFB. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 3534 8603 3531 8600 3526 8611 3531 8624
      3534 8621 3533 8620 3536 8617 3535 8616
      3536 8616
TIME...MOT...LOC 1437Z 226DEG 27KT 3532 8614 

TORNADO...RADAR INDICATED
HAIL...<.75

$$

30
1 follow-up statement
828 
WWUS54 KHUN 081444
SVSHUN

Severe Weather Statement
National Weather Service Huntsville AL
944 AM CDT Thu Apr 8 2021

TNC051-081454-
/O.EXP.KHUN.TO.W.0005.000000T0000Z-210408T1445Z/
Franklin TN-
944 AM CDT Thu Apr 8 2021

...THE TORNADO WARNING FOR NORTH CENTRAL FRANKLIN COUNTY WILL EXPIRE
AT 945 AM CDT...
        
The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning will
be allowed to expire.

LAT...LON 3534 8603 3531 8600 3526 8611 3531 8624
      3534 8621 3533 8620 3536 8617 3535 8616
      3536 8616
TIME...MOT...LOC 1444Z 226DEG 27KT 3535 8610 

$$

30

The office that day

Everything else NWS Huntsville, AL issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 8, 1:12 AM CDTSpecial Weather StatementHUNFranklin, Lincoln, Moore48 min
Apr 8, 9:28 AM CDTSpecial Weather StatementHUNFranklin32 min

Nearby

Tornado Warnings in Tennessee, 2021Every tornado warning in 2021Tornadoes in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.