Alert archive / Alabama / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 63, NWS Huntsville, AL

April 1, 2023DeKalb County, Marshall County, Alabama

NWS Huntsville, AL issued this severe thunderstorm warning at Apr 1, 2023, 4:14 AM CDT for DeKalb County, Marshall County, Alabama. It was in force for 46 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, 4:14 AM CDT (09:14 UTC)
Expired: Apr 1, 2023, 5:00 AM CDT
In force: 46 min
Issued by: NWS Huntsville, AL
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties DeKalb County, AL, Marshall County, AL

The radar

The Northeast Alabama radar (KHTX), 58 km from the middle of the area, began a volume at 09:13 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 31, 11:59 PM CDT	Tornado Watch	SPC	6 hr

The nearest sounding before it

Birmingham, AL (KBMX), launched 00:00Z, 9.2 hours before the alert went out and 153 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 Huntsville, AL wrote its last area forecast discussion before this severe thunderstorm warning went out at Apr 1, 4:12 AM CDT, 2 minutes earlier.

Area forecast discussion, Apr 1, 4:12 AM CDT, 2 minutes before

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In the hours before

Local storm report, Apr 1, 2:10 AM CDT, 2 hours 4 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HUNTSVILLE AL
210 AM CDT SAT APR 1 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0137 AM     TORNADO          6 N RED BAY             34.53N 88.14W
04/01/2023                   FRANKLIN           AL   OFFICIAL NWS OBS

            A TORNADO DEBRIS SIGNATURE (TDS) WAS
            DETECTED ON GWX RADAR.

&&

HC

Local storm report, Apr 1, 3:46 AM CDT, 28 minutes before

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  <meta name="viewport" content="width=device-width, initial-scale=1">
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</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
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The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 1, 1:22 AM CDT	Tornado Warning	HUN	Colbert, Franklin	23 min
Apr 1, 1:24 AM CDT	Severe Thunderstorm Warning	HUN	Colbert, Lauderdale	51 min
Apr 1, 1:30 AM CDT	Tornado Warning	HUN	Colbert, Lauderdale	30 min
Apr 1, 1:40 AM CDT	Tornado Warning Tornado observed	HUN	Colbert, Franklin	35 min
Apr 1, 2:03 AM CDT	Severe Thunderstorm Warning	HUN	Colbert, Franklin, Lawrence	42 min
Apr 1, 2:05 AM CDT	Severe Thunderstorm Warning	HUN	Lauderdale, Limestone	40 min
Apr 1, 2:40 AM CDT	Tornado Warning Tornado observed	HUN	Franklin, Lawrence	35 min
Apr 1, 3:04 AM CDT	Severe Thunderstorm Warning	HUN	Jackson, Madison	41 min
Apr 1, 3:06 AM CDT	Severe Thunderstorm Warning	HUN	Cullman, Lawrence, Morgan	24 min
Apr 1, 3:07 AM CDT	Tornado Warning	HUN	Madison	23 min
Apr 1, 3:19 AM CDT	Severe Thunderstorm Warning	HUN	Jackson, Madison	41 min
Apr 1, 3:20 AM CDT	Tornado Warning	HUN	Marshall, Morgan	25 min
Apr 1, 3:42 AM CDT	Severe Thunderstorm Warning	HUN	Cullman	33 min
Apr 1, 3:48 AM CDT	Severe Thunderstorm Warning	HUN	DeKalb, Jackson, Madison, Marshall	27 min
Apr 1, 3:52 AM CDT	Severe Thunderstorm Warning	HUN	DeKalb, Jackson	38 min
Apr 1, 3:25 AM CDT	Tornado Warning Tornado observedConsiderable damage threat	HUN	Franklin, Lincoln	21 min
Apr 1, 3:43 AM CDT	Severe Thunderstorm Warning	HUN	Franklin	32 min

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.