Alert archive / Alabama / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 107, NWS Birmingham, AL

April 1, 2023Calhoun County, Cherokee County, Etowah County, Alabama

NWS Birmingham, AL issued this severe thunderstorm warning at Apr 1, 2023, 5:11 AM CDT for Calhoun County, Cherokee County, Etowah County, Alabama. It was in force for 49 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Apr 1, 2023, 5:11 AM CDT (10:11 UTC)
Expired: Apr 1, 2023, 6:00 AM CDT
In force: 49 min
Issued by: NWS Birmingham, AL
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Calhoun County, AL, Cherokee County, AL, Etowah County, AL

The radar

The Northeast Alabama radar (KHTX), 107 km from the middle of the area, began a volume at 10:12 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
Apr 1, 3:19 AM CDT	Tornado Watch	SPC	5 hr

The nearest sounding before it

Birmingham, AL (KBMX), launched 00:00Z, 10.2 hours before the alert went out and 127 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: 169 J/kg
Mixed-layer CIN: -41 J/kg
Mixed-layer LCL: 1105 m above ground
0-6 km bulk shear: 55 kt
0-1 km storm-relative helicity: 142 m²/s²
0-3 km storm-relative helicity: 362 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 0.8

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Birmingham, AL wrote its last area forecast discussion before this severe thunderstorm warning went out at Apr 1, 2:45 AM CDT, 2 hours 26 minutes earlier.

Area forecast discussion, Apr 1, 2:45 AM CDT, 2 hours 26 minutes before

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Hazardous weather outlook, Apr 1, 4:09 AM CDT, 1 hour 2 minutes before

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In the hours before

Special weather statement, Apr 1, 4:07 AM CDT, 1 hour 4 minutes before

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Special weather statement, Apr 1, 4:13 AM CDT, 58 minutes before

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Local storm report, Apr 1, 4:30 AM CDT, 41 minutes before

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Local storm report, Apr 1, 4:41 AM CDT, 30 minutes before

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Special weather statement, Apr 1, 4:44 AM CDT, 27 minutes before

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Special weather statement, Apr 1, 4:51 AM CDT, 20 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 1, 1:55 AM CDT	Tornado Warning	BMX	Marion	65 min
Apr 1, 2:44 AM CDT	Tornado Warning Tornado observed	BMX	Winston	32 min
Apr 1, 2:49 AM CDT	Severe Thunderstorm Warning	BMX	Fayette, Lamar, Marion	56 min
Apr 1, 3:23 AM CDT	Severe Thunderstorm Warning	BMX	Walker, Winston	52 min
Apr 1, 4:07 AM CDT	Special Weather Statement	BMX	Blount	53 min
Apr 1, 4:13 AM CDT	Special Weather Statement	BMX	Walker	32 min
Apr 1, 4:44 AM CDT	Special Weather Statement	BMX	DeKalb	31 min
Apr 1, 4:51 AM CDT	Special Weather Statement	BMX	Etowah	39 min
Apr 1, 5:52 AM CDT	Special Weather Statement	BMX	Calhoun	53 min
Apr 1, 6:11 AM CDT	Special Weather Statement	BMX	St. Clair	34 min
Apr 1, 6:55 AM CDT	Special Weather Statement	BMX	Autauga, Dallas	35 min
Apr 1, 7:27 AM CDT	Special Weather Statement	BMX	Autauga, Elmore	48 min
Apr 1, 7:45 AM CDT	Special Weather Statement	BMX	Dallas	45 min
Apr 1, 8:04 AM CDT	Special Weather Statement	BMX	Macon	41 min
Apr 1, 10:12 AM CDT	Special Weather Statement	BMX	Bullock	33 min
Apr 1, 10:42 AM CDT	Special Weather Statement	BMX	Russell	33 min
Apr 1, 11:52 AM CDT	Tornado Warning	BMX	Barbour	15 min
Apr 1, 2:45 PM CDT	Wind Advisory	BMX	Fayette, Lamar, Marion, Pickens, Tuscaloosa	4 hr

Nearby

Severe Thunderstorm Warnings in Alabama, 2023 Every severe thunderstorm warning in 2023

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.