Alert archive / Tennessee / Tornado Warnings in 2017

Tornado Warning 2, NWS Huntsville, AL

March 21, 2017Franklin County, Tennessee

NWS Huntsville, AL issued this tornado warning at Mar 21, 2017, 5:03 PM CDT for Franklin County, Tennessee. It was in force for 12 min. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Mar 21, 2017, 5:03 PM CDT (22:03 UTC)
Expired: Mar 21, 2017, 5:15 PM CDT
In force: 12 min
Issued by: NWS Huntsville, AL
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 1.0 in

County Franklin County, TN

The radar

The Northeast Alabama radar (KHTX), 28 km from the middle of the area, began a volume at 22:05 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.

What was reported inside it

Time	Report	Where	Remark
Mar 21, 5:13 PM CDT	TSTM WND DMG	Belvidere, TN	WIDESPREAD TREE DAMAGE ACROSS THE SOUTHERN HALF OF FRANKLIN COUNTY
Mar 21, 5:13 PM CDT	TSTM WND DMG	Huntland, TN	TREES DOWN ACROSS THE TOWN

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Mar 21, 2:33 PM CDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 12:00Z, 10.1 hours before the alert went out and 114 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 215 J/kg
Mixed-layer CIN: -332 J/kg
Mixed-layer LCL: 1125 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 157 m²/s²
0-3 km storm-relative helicity: 207 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

658 
WFUS54 KHUN 212203
TORHUN
TNC051-212215-
/O.NEW.KHUN.TO.W.0002.170321T2203Z-170321T2215Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Huntsville AL
503 PM CDT TUE MAR 21 2017

The National Weather Service in Huntsville Alabama has issued a

* Tornado Warning for...
  Southwestern Franklin County in Middle Tennessee...

* Until 515 PM CDT
    
* At 503 PM CDT, a severe thunderstorm capable of producing a tornado
  was located near Huntland, or 10 miles south of Lynchburg, moving
  southeast at 35 mph.

  HAZARD...Tornado and quarter size hail. 

  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. 

* This tornadic thunderstorm will remain over mainly rural areas of
  southwestern Franklin County, including the following locations:
  Lexie Crossroads, Beans Creek, Harmony, Maxwell and Belvidere.

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 3515 8600 3499 8610 3507 8632 3513 8631
      3515 8633 3515 8632 3517 8632 3517 8630
      3520 8631 3521 8629 3522 8631
TIME...MOT...LOC 2203Z 293DEG 30KT 3513 8630 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

Stumpf

The office that day

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

Issued	Product	Office	Counties	Lasted
Mar 20, 8:33 PM CDT	Special Weather Statement	HUN	Franklin	42 min
Mar 21, 4:09 PM CDT	Severe Thunderstorm Warning	HUN	Lincoln, Moore	36 min
Mar 21, 4:33 PM CDT	Severe Thunderstorm Warning	HUN	Franklin, Lincoln, Moore	27 min
Mar 21, 4:57 PM CDT	Severe Thunderstorm Warning	HUN	Franklin, Lincoln, Moore	33 min
Mar 21, 5:26 PM CDT	Severe Thunderstorm Warning	HUN	Franklin	34 min

Nearby

Tornado Warnings in Tennessee, 2017 Every tornado warning in 2017 Tornadoes in 2017

Sources

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