Alert archive / Alabama / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 76, NWS Huntsville, AL

August 11, 2021Jackson County, Alabama

NWS Huntsville, AL issued this severe thunderstorm warning at Aug 11, 2021, 4:01 PM CDT for Jackson County, Alabama. It was in force for 29 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
Aug 11, 2021, 4:01 PM CDT (21:01 UTC)
Expired
Aug 11, 2021, 4:30 PM CDT
In force
29 min
Issued by
NWS Huntsville, AL
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Jackson County, AL

The radar

The Northeast Alabama radar (KHTX), 10 km from the middle of the area, began a volume at 21:03 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, 9.0 hours before the alert went out and 151 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 2021-08-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2131 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Nashville Metro, TN at 12:00Z on 2021-08-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -18 square meters per square second.1939Sfc1 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
2131 J/kg
Mixed-layer CIN
-37 J/kg
Mixed-layer LCL
942 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
-18 m²/s²
0-3 km storm-relative helicity
29 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

284 
WUUS54 KHUN 112101
SVRHUN
ALC071-112130-
/O.NEW.KHUN.SV.W.0076.210811T2101Z-210811T2130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Huntsville AL
401 PM CDT Wed Aug 11 2021

The National Weather Service in Huntsville Alabama has issued a

* Severe Thunderstorm Warning for...
  North central Jackson County in northeastern Alabama...

* Until 430 PM CDT.

* At 401 PM CDT, a severe thunderstorm was located near Skyline, 
  moving south at 10 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

* Locations impacted include...
  Hytop and Fackler. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3489 8611 3497 8597 3478 8586 3473 8609
TIME...MOT...LOC 2101Z 358DEG 12KT 3486 8601 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

KTW
1 follow-up statement
745 
WWUS54 KHUN 112123
SVSHUN

Severe Weather Statement
National Weather Service Huntsville AL
423 PM CDT Wed Aug 11 2021

ALC071-112133-
/O.EXP.KHUN.SV.W.0076.000000T0000Z-210811T2130Z/
Jackson AL-
423 PM CDT Wed Aug 11 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTH CENTRAL JACKSON COUNTY
WILL EXPIRE AT 430 PM CDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.

LAT...LON 3489 8611 3497 8597 3478 8586 3473 8609
TIME...MOT...LOC 2123Z 358DEG 12KT 3479 8601 

$$

KTW

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 11, 3:05 PM CDTSpecial Weather StatementHUNJackson40 min
Aug 11, 3:21 PM CDTSpecial Weather StatementHUNMadison24 min
Aug 11, 3:32 PM CDTSpecial Weather StatementHUNDeKalb28 min
Aug 11, 3:47 PM CDTSpecial Weather StatementHUNMarshall28 min
Aug 11, 3:55 PM CDTSpecial Weather StatementHUNJackson35 min
Aug 11, 4:07 PM CDTSpecial Weather StatementHUNLawrence38 min
Aug 11, 4:22 PM CDTSevere Thunderstorm WarningHUNFranklin, Lawrence23 min
Aug 11, 4:35 PM CDTSpecial Weather StatementHUNMorgan40 min
Aug 11, 4:43 PM CDTSpecial Weather StatementHUNMadison47 min
Aug 11, 5:09 PM CDTSpecial Weather StatementHUNMadison, Morgan21 min
Aug 11, 5:17 PM CDTSpecial Weather StatementHUNJackson28 min
Aug 11, 5:21 PM CDTSevere Thunderstorm WarningHUNJackson24 min
Aug 11, 5:38 PM CDTSevere Thunderstorm WarningHUNJackson, Madison25 min
Aug 11, 5:46 PM CDTSpecial Weather StatementHUNJackson29 min
Aug 11, 6:17 PM CDTFlash Flood WarningHUNJackson, Madison, Marshall, Morgan79 min

Nearby

Severe Thunderstorm Warnings in Alabama, 2021Every severe thunderstorm warning 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.