Alert archive / Alabama / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 24, NWS Huntsville, AL

March 28, 2021Jackson County, Alabama; Franklin County, Tennessee

NWS Huntsville, AL issued this severe thunderstorm warning at Mar 28, 2021, 4:26 AM CDT for Jackson County, Alabama; Franklin County, Tennessee. It was in force for 34 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: Mar 28, 2021, 4:26 AM CDT (09:26 UTC)
Expired: Mar 28, 2021, 5:00 AM CDT
In force: 34 min
Issued by: NWS Huntsville, AL
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Jackson County, AL, Franklin County, TN

The radar

The Northeast Alabama radar (KHTX), 2 km from the middle of the area, began a volume at 09:30 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 watch it was issued in

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

Issued	Product	Office	Lasted
Mar 27, 11:27 PM CDT	Tornado Watch	SPC	8 hr

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 00:00Z, 9.4 hours before the alert went out and 139 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: 200 J/kg
Mixed-layer CIN: -290 J/kg
Mixed-layer LCL: 839 m above ground
0-6 km bulk shear: 62 kt
0-1 km storm-relative helicity: 341 m²/s²
0-3 km storm-relative helicity: 458 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 3.8

Open this sounding in Storm Lab

The text

As transmitted.

050 
WUUS54 KHUN 280926
SVRHUN
ALC071-TNC051-281000-
/O.NEW.KHUN.SV.W.0024.210328T0926Z-210328T1000Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Huntsville AL
426 AM CDT Sun Mar 28 2021

The National Weather Service in Huntsville Alabama has issued a

* Severe Thunderstorm Warning for...
  Northwestern Jackson County in northeastern Alabama...
  Southeastern Franklin County in Middle Tennessee...

* Until 500 AM CDT.

* At 426 AM CDT, a severe thunderstorm was located near New Market,
  or 11 miles east of Moores Mill, moving east at 70 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Locations impacted include...
  Stevenson, Skyline, Anderson, Hytop, Bass, Francisco, Princeton,
  Jericho, Estillfork and Hollytree.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 600 AM CDT for north central
and northeastern Alabama...and Middle Tennessee.

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

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3488 8579 3476 8629 3490 8633 3491 8631
      3493 8632 3495 8629 3492 8626 3494 8626
      3498 8630 3516 8587 3511 8586 3499 8586
      3499 8582
TIME...MOT...LOC 0926Z 248DEG 59KT 3487 8632 

HAIL...<.75IN
WIND...60MPH
 
$$

GH

1 follow-up statement

301 
WWUS54 KHUN 280953
SVSHUN

Severe Weather Statement
National Weather Service Huntsville AL
453 AM CDT Sun Mar 28 2021

ALC071-TNC051-281002-
/O.EXP.KHUN.SV.W.0024.000000T0000Z-210328T1000Z/
Jackson AL-Franklin TN-
453 AM CDT Sun Mar 28 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN JACKSON AND
SOUTHEASTERN FRANKLIN COUNTIES WILL EXPIRE AT 500 AM CDT...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning will be allowed to expire.  However heavy rain
is still possible with this thunderstorm.

A Tornado Watch remains in effect until 600 AM CDT for north central
and northeastern Alabama...and Middle Tennessee.

LAT...LON 3488 8579 3476 8629 3490 8633 3491 8631
      3493 8632 3495 8629 3492 8626 3494 8626
      3498 8630 3516 8587 3511 8586 3499 8586
      3499 8582
TIME...MOT...LOC 0952Z 248DEG 59KT 3502 8586 

$$

GH

The office that day

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

Issued	Product	Office	Counties	Lasted
Mar 28, 12:31 AM CDT	Severe Thunderstorm Warning	HUN	Colbert, Lauderdale	44 min
Mar 28, 1:13 AM CDT	Special Weather Statement	HUN	Lauderdale	47 min
Mar 28, 1:52 AM CDT	Flash Flood Warning	HUN	Lauderdale	3 hr
Mar 28, 2:39 AM CDT	Special Weather Statement	HUN	Colbert	51 min
Mar 28, 2:45 AM CDT	Special Weather Statement	HUN	Franklin	45 min
Mar 28, 3:09 AM CDT	Severe Thunderstorm Warning	HUN	Colbert, Franklin, Lawrence	36 min
Mar 28, 3:34 AM CDT	Severe Thunderstorm Warning	HUN	Lawrence, Limestone, Morgan	26 min
Mar 28, 3:58 AM CDT	Severe Thunderstorm Warning	HUN	Jackson, Limestone, Madison, Morgan	47 min
Mar 28, 4:46 AM CDT	Severe Thunderstorm Warning	HUN	Jackson, Limestone, Madison, Morgan	44 min
Mar 28, 5:02 AM CDT	Severe Thunderstorm Warning	HUN	Cullman	28 min
Mar 28, 5:21 AM CDT	Severe Thunderstorm Warning	HUN	Jackson	24 min
Mar 28, 5:30 AM CDT	Severe Thunderstorm Warning	HUN	Cullman	30 min
Mar 28, 5:41 AM CDT	Areal Flood Warning	HUN	Madison	3 hr
Mar 28, 5:57 AM CDT	Severe Thunderstorm Warning	HUN	DeKalb, Marshall	33 min
Mar 28, 6:26 AM CDT	Special Weather Statement	HUN	DeKalb	34 min
Mar 27, 7:47 PM CDT	Special Weather Statement	HUN	Franklin	28 min
Mar 28, 2:18 AM CDT	Special Weather Statement	HUN	Lincoln, Moore	42 min

Nearby

Severe Thunderstorm Warnings in Alabama, 2021 Severe Thunderstorm Warnings in Tennessee, 2021 Every 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.