Alert archive / Alabama / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 110, NWS Huntsville, AL

August 30, 2020Jackson County, Alabama

NWS Huntsville, AL issued this severe thunderstorm warning at Aug 30, 2020, 4:47 PM CDT for Jackson County, Alabama. It was in force for 28 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: Aug 30, 2020, 4:47 PM CDT (21:47 UTC)
Expired: Aug 30, 2020, 5:15 PM CDT
In force: 28 min
Issued by: NWS Huntsville, AL
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

County Jackson County, AL

The radar

The Northeast Alabama radar (KHTX), 19 km from the middle of the area, began a volume at 21:47 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

Peachtre/Fal Fld, GA (KFFC), launched 12:00Z, 9.8 hours before the alert went out and 209 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: 1183 J/kg
Mixed-layer CIN: -20 J/kg
Mixed-layer LCL: 694 m above ground
0-6 km bulk shear: 3 kt
0-1 km storm-relative helicity: -13 m²/s²
0-3 km storm-relative helicity: -7 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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 Aug 30, 2:36 PM CDT, 2 hours 11 minutes earlier.

Area forecast discussion, Aug 30, 2:36 PM CDT, 2 hours 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>

Hazardous weather outlook, Aug 30, 12:13 PM CDT, 4 hours 34 minutes before

Hazardous Weather Outlook
National Weather Service Huntsville AL
1213 PM CDT Sun Aug 30 2020

ALZ001>010-016-TNZ076-096-097-311100-
Lauderdale-Colbert-Franklin AL-Lawrence-Limestone-Madison-Morgan-
Marshall-Jackson-DeKalb-Cullman-Moore-Lincoln-Franklin TN-
1213 PM CDT Sun Aug 30 2020

This Hazardous Weather Outlook is for north central Alabama,
northeast Alabama, northwest Alabama and southern middle Tennessee.

.DAY ONE...This afternoon and tonight.

Thunderstorms will become numerous across the area this afternoon and
evening, with gusty winds and heavy rainfall possible. Localized
flooding could result from slow moving storms or storms that
repeatedly move across the same area.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

Thunderstorms will be possible on Monday and Tuesday, with gusty
winds and heavy rainfall possible. Lesser coverage of storms is
expected Wednesday through Saturday, with isolated thunderstorms
possible each day during this time.

.SPOTTER INFORMATION STATEMENT...

Activation of storm spotters and emergency management personnel is
not anticipated at this time.

12

In the hours before

Special weather statement, Aug 30, 3:29 PM CDT, 1 hour 18 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, Aug 30, 3:49 PM CDT, 58 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, Aug 30, 4:05 PM CDT, 42 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, Aug 30, 4:28 PM CDT, 19 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, Aug 30, 4:32 PM CDT, 15 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, Aug 30, 4:42 PM CDT, 5 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.

Issued	Product	Office	Counties	Lasted
Aug 30, 2:19 PM CDT	Special Weather Statement	HUN	Madison	41 min
Aug 30, 2:31 PM CDT	Special Weather Statement	HUN	DeKalb	14 min
Aug 30, 2:50 PM CDT	Special Weather Statement	HUN	DeKalb	25 min
Aug 30, 2:55 PM CDT	Special Weather Statement	HUN	Lauderdale	50 min
Aug 30, 3:07 PM CDT	Special Weather Statement	HUN	Jackson	38 min
Aug 30, 3:18 PM CDT	Special Weather Statement	HUN	DeKalb	27 min
Aug 30, 3:44 PM CDT	Severe Thunderstorm Warning	HUN	Lauderdale, Limestone	31 min
Aug 30, 3:49 PM CDT	Special Weather Statement	HUN	Morgan	26 min
Aug 30, 4:05 PM CDT	Special Weather Statement	HUN	Morgan	40 min
Aug 30, 4:28 PM CDT	Special Weather Statement	HUN	Franklin	32 min
Aug 30, 4:32 PM CDT	Special Weather Statement	HUN	Jackson	43 min
Aug 30, 4:42 PM CDT	Special Weather Statement	HUN	Colbert, Lauderdale	48 min
Aug 30, 4:58 PM CDT	Flash Flood Warning	HUN	Colbert, Lauderdale	3 hr
Aug 30, 5:11 PM CDT	Special Weather Statement	HUN	Lauderdale, Lawrence	49 min
Aug 30, 5:32 PM CDT	Flash Flood Warning	HUN	Cullman, Lawrence, Morgan	83 min
Aug 30, 6:55 PM CDT	Areal Flood Warning	HUN	Cullman, Lawrence, Morgan	98 min
Aug 30, 3:31 AM CDT	Special Weather Statement	HUN	Lincoln, Moore	44 min
Aug 30, 5:59 PM CDT	Special Weather Statement	HUN	Franklin, Moore	31 min
Aug 30, 6:32 PM CDT	Special Weather Statement	HUN	Moore	43 min
Aug 30, 6:35 PM CDT	Special Weather Statement	HUN	Franklin	40 min

Nearby

Severe Thunderstorm Warnings in Alabama, 2020 Every severe thunderstorm warning in 2020

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.