Alert archive / Alabama / Severe Thunderstorm Warnings in 2006

Severe Thunderstorm Warning 69, NWS Huntsville, AL

April 20, 2006Marshall County, Alabama

NWS Huntsville, AL issued this severe thunderstorm warning at Apr 20, 2006, 3:16 PM CDT for Marshall County, Alabama. It was in force for 44 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 20, 2006, 3:16 PM CDT (20:16 UTC)
Expired
Apr 20, 2006, 4:00 PM CDT
In force
44 min
Issued by
NWS Huntsville, AL
Area
Counties, with a storm outline in the text

County Marshall County, AL

The radar

The Northeast Alabama radar (KHTX), 66 km from the middle of the area, began a volume at 20:18 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.

IssuedProductOfficeLasted
Apr 20, 11:38 AM CDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Birmingham, AL (KBMX), launched 12:00Z, 8.3 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-pSkew-T log-p diagram, Birmingham, AL at 12:00Z on 2006-04-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 488 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, Birmingham, AL at 12:00Z on 2006-04-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -119 square meters per square second.19395878Sfc1 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
488 J/kg
Mixed-layer CIN
-279 J/kg
Mixed-layer LCL
1148 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
-119 m²/s²
0-3 km storm-relative helicity
-98 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

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 20, 10:45 AM CDT, 4 hours 31 minutes earlier.

Area forecast discussion, Apr 20, 10:45 AM CDT, 4 hours 31 minutes before
<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</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.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>
Hazardous weather outlook, Apr 20, 12:40 PM CDT, 2 hours 36 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HUNTSVILLE AL
1240 PM CDT THU APR 20 2006

ALZ001>010-016-TNZ076-096-097-210230-
COLBERT-CULLMAN-DE KALB-FRANKLIN AL-FRANKLIN TN-JACKSON-LAUDERDALE-
LAWRENCE-LIMESTONE-LINCOLN-MADISON-MARSHALL-MOORE-MORGAN-
1240 PM CDT THU APR 20 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH ALABAMA AND PORTIONS
OF SOUTHERN MIDDLE TENNESSEE.

.DAY ONE...THROUGH TONIGHT...

SCATTERED TO NUMEROUS THUNDERSTORMS WILL DEVELOP THROUGHOUT THE
AFTERNOON AND EVENING HOURS AS UPPER LEVEL ENERGY MOVES THROUGH
AND INTERACTS WITH A VERY UNSTABLE AIR MASS. SOME OF THESE
THUNDERSTORMS MAY BECOME SEVERE WITH LARGE HAIL AND DAMAGING WINDS
BEING THE MAIN THREATS.  LOCALLY HEAVY RAINFALL WILL ALSO BE A
POSSIBILITY DUE TO THE SLOW MOVEMENT OF THE THUNDERSTORMS.

THUNDERSTORMS WILL GRADUALLY DIMINISH IN COVERAGE AND INTENSITY
OVERNIGHT...ALTHOUGH AN ISOLATED STRONG TO SEVERE STORM OR TWO
CANNOT BE RULED OUT.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY...

A COLD FRONT WILL MOVE IN FROM THE WEST ON FRIDAY ALONG WITH A
STRONG UPPER TROUGH. THAT COMBINATION WILL RESULT IN MORE
THUNDERSTORM COVERAGE OVER THE AREA...AND A SLIGHT RISK OF SEVERE
THUNDERSTORMS WITH DAMAGING WINDS AND ISOLATED TORNADOES THE MAIN
THREATS. THE ACTIVITY COULD EXTEND WELL INTO THE EVENING...THEN
DIMINISH OVERNIGHT AND EARLY SATURDAY AS THE FRONT MOVES THROUGH.

.SPOTTER CALL TO ACTION STATEMENT...

ACTIVATION OF STORM SPOTTERS AND EMERGENCY MANAGEMENT PERSONNEL
MAY BE NECESSARY AT TIMES THROUGH FRIDAY.

In the hours before

Local storm report, Apr 20, 10:27 AM CDT, 4 hours 49 minutes before
<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</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.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>
Special weather statement, Apr 20, 10:31 AM CDT, 4 hours 45 minutes before
<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</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.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>
Special weather statement, Apr 20, 11:35 AM CDT, 3 hours 41 minutes before
<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</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.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>
Local storm report, Apr 20, 1:07 PM CDT, 2 hours 9 minutes before
<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</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.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>
Local storm report, Apr 20, 3:05 PM CDT, 11 minutes before
<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</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.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 19, 7:38 PM CDTSevere Thunderstorm WarningHUNDeKalb25 min
Apr 19, 7:44 PM CDTSevere Thunderstorm WarningHUNJackson22 min
Apr 19, 7:44 PM CDTSevere Thunderstorm WarningHUNCullman46 min
Apr 19, 7:55 PM CDTSevere Thunderstorm WarningHUNCullman50 min
Apr 19, 8:22 PM CDTFlash Flood WarningHUNCullman3 hr
Apr 19, 8:27 PM CDTSevere Thunderstorm WarningHUNCullman48 min
Apr 19, 9:13 PM CDTSevere Thunderstorm WarningHUNCullman47 min
Apr 19, 11:13 PM CDTFlash Flood WarningHUNCullman6 hr
Apr 19, 11:52 PM CDTSevere Thunderstorm WarningHUNMorgan38 min
Apr 20, 12:28 AM CDTSevere Thunderstorm WarningHUNMorgan47 min
Apr 20, 8:04 AM CDTSevere Thunderstorm WarningHUNColbert41 min
Apr 20, 9:44 AM CDTSevere Thunderstorm WarningHUNLauderdale31 min
Apr 20, 10:07 AM CDTSevere Thunderstorm WarningHUNLimestone38 min
Apr 20, 11:16 AM CDTSevere Thunderstorm WarningHUNFranklin19 min
Apr 20, 2:40 PM CDTSevere Thunderstorm WarningHUNCullman50 min
Apr 20, 3:28 PM CDTSevere Thunderstorm WarningHUNCullman33 min
Apr 20, 4:12 PM CDTSevere Thunderstorm WarningHUNDeKalb33 min
Apr 20, 4:35 PM CDTSevere Thunderstorm WarningHUNMarshall25 min
Apr 20, 5:33 PM CDTFlash Flood WarningHUNCullman3 hr
Apr 20, 5:36 PM CDTSevere Thunderstorm WarningHUNCullman39 min
Apr 20, 5:38 PM CDTSevere Thunderstorm WarningHUNDeKalb, Marshall52 min
Apr 20, 6:10 PM CDTSevere Thunderstorm WarningHUNCullman, Morgan50 min
Apr 20, 6:14 PM CDTTornado WarningHUNCullman, Morgan46 min
Apr 20, 6:27 PM CDTTornado WarningHUNMarshall33 min
Apr 20, 6:42 PM CDTSevere Thunderstorm WarningHUNMorgan33 min
Apr 20, 6:58 PM CDTSevere Thunderstorm WarningHUNMadison47 min

Nearby

Severe Thunderstorm Warnings in Alabama, 2006Every severe thunderstorm warning in 2006

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.