Alert archive / Alabama / Tornado Warnings in 2021

Tornado Warning 8, NWS Huntsville, AL

August 18, 2021Limestone County, Alabama

NWS Huntsville, AL issued this tornado warning at Aug 18, 2021, 6:47 PM CDT for Limestone County, Alabama. It was in force for 28 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: Aug 18, 2021, 6:47 PM CDT (23:47 UTC)
Expired: Aug 18, 2021, 7:15 PM CDT
In force: 28 min
Issued by: NWS Huntsville, AL
Area: Storm-based polygon
Tornado: Observed
Hail: 0.75 in

County Limestone County, AL

The radar

The Northeast Alabama radar (KHTX), 76 km from the middle of the area, began a volume at 23:50 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
Aug 18, 6:51 PM CDT	TORNADO	2 N Athens, AL	TORNADO SPOTTED MOVING AWAY FROM OBSERVERS, WHO WERE LOCATED ALONG US HWY 31 IN TANNER.
Aug 18, 7:00 PM CDT	TSTM WND DMG	1 Nne Athens, AL	DELAYED REPORT. TREE DOWN ACROSS CRESTVIEW ST. TIME ESTIMATED ON BY RADAR.

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

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 12:00Z, 11.8 hours before the alert went out and 154 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: 259 J/kg
Mixed-layer CIN: -49 J/kg
Mixed-layer LCL: 919 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 70 m²/s²
0-3 km storm-relative helicity: 72 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

813 
WFUS54 KHUN 182347
TORHUN
ALC083-190015-
/O.NEW.KHUN.TO.W.0008.210818T2347Z-210819T0015Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Huntsville AL
647 PM CDT Wed Aug 18 2021

The National Weather Service in Huntsville Alabama has issued a

* Tornado Warning for...
  East central Limestone County in north central Alabama...

* Until 715 PM CDT

* At 647 PM CDT, a confirmed tornado was located over Athens, moving
  east at 35 mph.

  HAZARD...Damaging tornado. 

  SOURCE...Weather spotters confirmed tornado. 

  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. 

* The tornado will be near...
  Harvest around 705 PM CDT. 
  Madison around 715 PM CDT. 

Other locations impacted by this tornadic thunderstorm include French
Mill and Capshaw.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To repeat, a tornado is on the ground. 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 3467 8679 3478 8707 3485 8705 3486 8678
TIME...MOT...LOC 2347Z 280DEG 30KT 3481 8699 

TORNADO...OBSERVED
MAX HAIL SIZE...<.75 IN

$$

09

1 follow-up statement

556 
WWUS54 KHUN 190008
SVSHUN

Severe Weather Statement
National Weather Service Huntsville AL
708 PM CDT Wed Aug 18 2021

ALC083-190017-
/O.EXP.KHUN.TO.W.0008.000000T0000Z-210819T0015Z/
Limestone AL-
708 PM CDT Wed Aug 18 2021

...THE TORNADO WARNING FOR EAST CENTRAL LIMESTONE COUNTY WILL EXPIRE
AT 715 PM CDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning will be allowed to expire.  However gusty
winds are still possible with this thunderstorm.

LAT...LON 3467 8679 3478 8707 3485 8705 3486 8678
TIME...MOT...LOC 0007Z 280DEG 30KT 3478 8680 

$$

09

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 18, 4:51 PM CDT	Special Weather Statement	HUN	Colbert	39 min
Aug 18, 5:46 PM CDT	Areal Flood Warning	HUN	Colbert, Lauderdale	89 min
Aug 18, 6:09 PM CDT	Areal Flood Warning	HUN	Colbert, Lauderdale	96 min
Aug 18, 6:36 PM CDT	Tornado Warning	HUN	Limestone	24 min

Nearby

Tornado Warnings in Alabama, 2021 Every tornado warning in 2021 Tornadoes 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.