Alert archive / Alabama / Severe Thunderstorm Warnings in 2013

Severe Thunderstorm Warning 98, NWS Huntsville, AL

December 21, 2013Colbert County, Franklin County, Lauderdale County, Alabama

NWS Huntsville, AL issued this severe thunderstorm warning at Dec 21, 2013, 9:29 PM CST for Colbert County, Franklin County, Lauderdale 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
Dec 21, 2013, 9:29 PM CST (03:29 UTC)
Expired
Dec 21, 2013, 10:15 PM CST
In force
46 min
Issued by
NWS Huntsville, AL
Area
Storm-based polygon

Counties Colbert County, AL, Franklin County, AL, Lauderdale County, AL

The radar

The Columbus AFB radar (KGWX), 101 km from the middle of the area, began a volume at 03:33 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
Dec 21, 8:16 PM CSTTornado WatchSPC6 hr

The nearest sounding before it

Birmingham, AL (KBMX), launched 00:00Z, 3.5 hours before the alert went out and 190 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 00:00Z on 2013-12-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 714 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 00:00Z on 2013-12-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 331 square meters per square second.1939587897Sfc1 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
714 J/kg
Mixed-layer CIN
-3 J/kg
Mixed-layer LCL
711 m above ground
0-6 km bulk shear
56 kt
0-1 km storm-relative helicity
331 m²/s²
0-3 km storm-relative helicity
388 m²/s²
Significant tornado parameter
1.8
Supercell composite
6.3

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 Dec 21, 6:55 PM CST, 2 hours 34 minutes earlier.

Area forecast discussion, Dec 21, 6:55 PM CST, 2 hours 34 minutes before
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE HUNTSVILLE AL
655 PM CST SAT DEC 21 2013

.MESOSCALE UPDATE...
00Z RAOBS SUGGEST A GRADIENT IN SFC-BASED INSTABILITY FROM N-S BASED
ON A NASHVILLE SOUNDING WHICH HAS LITTLE CAPE, WHILE BMX AND JAN SHOW
MORE SUBSTANTIAL CAPE IN THE 400-800 J/KG RANGE. SRH IS BASED LARGELY
IN THE LOWEST 1KM WITH VALUES NEARING 600 M2/S2 AT NASHVILLE AND
350-400 M2/S2 AT BIRMINGHAM. AMPLE LOW LEVEL FLOW IS ADVECTING DEW
POINTS INTO THE M60S OVER NRN AL NOW WITH TEMPS STILL IN THE L-M70S
(RECORD HIGH TEMP AT KMSL). PRIND ARE THAT THE SQLN WILL REACH THE AL
STATE LINE IN OUR CWA BY 03-04Z. CONVERGENCE LINES/SHRA ARE
DEVELOPING AHEAD OF THE SQLN WHICH HAS US SOMEWHAT CONCERNED FOR DISCRETE
SUPERCELL DEVELOPMENT BEFORE THE LINE OVERTAKES THIS. THE CAPE VALUES
WOULD SUGGEST THIS TO BE MORE LIKELY JUST S-SW OF OUR CWA, BUT GIVEN
ADVECTION FIELDS, I CANNOT RULE THIS OUT IN OUR AREA AS WELL. BASED
UPON THE MD ISSUED BY SPC, WE SHOULD SEE A WATCH ISSUED FOR OUR AREA
SOON. WE COULD SEE A WEAKENING TREND AS THE MAX SFC PRESSURE FALLS
ARE LIFTING WELL NORTH INTO IN/KY. IN THIS CASE, SOME
MOMENTUM/CONVERGENCE MAY WEAKEN SOMEWHAT AND WIND FIELDS BECOME MORE
PARALLEL TO THE LINE. IN THIS CASE, HEAVY RAIN MAY BECOME MORE OF A
PROBLEM.

KULA

&&

.AVIATION...
/ISSUED 522 PM CST SAT DEC 21 2013/
FOR 00Z TAFS... WINDY CONDITIONS WILL PREVAIL TONIGHT IN ADVANCE OF
SQUALL LINE. SPORADIC SHRA WILL OCCUR AHEAD OF THE SOLID LINE OF
SHOWERS AND THUNDERSTORMS, ALONG WITH VARIABLE MVFR CIGS AT TIMES.
THE SQUALL LINE MAY PRODUCE STRONG WINDS OF AT LEAST 40KT, BUT IT
COULD BE HIGHER ALONG WITH BRIEF HEAVY RAINFALL LOWERING VSBYS TO 1SM
OR LESS. BEHIND THE LINE, STRATIFORM RAINFALL AND MVFR CIGS WILL
OCCUR THRU MOST OF SUNDAY MORNING BEFORE SOME DRIER AIR WORKS IN
DURING THE AFTERNOON HOURS.

AK

&&

.HUN WATCHES/WARNINGS/ADVISORIES...
AL...WIND ADVISORY UNTIL 3 AM CST SUNDAY FOR ALZ001>010-016.

TN...WIND ADVISORY UNTIL 3 AM CST SUNDAY FOR TNZ076-096-097.

&&

FOR MORE INFORMATION PLEASE VISIT OUR WEBSITE
AT WEATHER.GOV/HUNTSVILLE.
Hazardous weather outlook, Dec 21, 8:42 PM CST, 47 minutes before
HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE HUNTSVILLE AL
842 PM CST SAT DEC 21 2013

ALZ001>010-016-TNZ076-096-097-220900-
LAUDERDALE-COLBERT-FRANKLIN AL-LAWRENCE-LIMESTONE-MADISON-MORGAN-
MARSHALL-JACKSON-DEKALB-CULLMAN-MOORE-LINCOLN-FRANKLIN TN-
842 PM CST SAT DEC 21 2013

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

.DAY ONE...TONIGHT...

A SQUALL LINE WILL MOVE EAST ACROSS NORTH ALABAMA AND SOUTHERN
TENNESSEE OVERNIGHT. THE STORMS WILL PRODUCE DAMAGING WINDS IN EXCESS
OF 60 MPH. SHORT LIVED TORNADOES REMAIN POSSIBLE ALONG THIS LINE. A
TORNADO WATCH IS IN EFFECT UNTIL 2 AM.

THE LINE SHOULD APPROACH THE I-65 CORRIDOR IN NORTH ALABAMA AND
SOUTHERN MIDDLE TENNESSEE BETWEEN 11 PM AND 1 AM AND EXIT NORTHEAST
ALABAMA BY 2 TO 3 AM.

LOCALLY HEAVY RAINFALL OF 1 TO 2 INCHES WILL ALSO OCCUR WHICH COULD
LEAD TO PONDING OF WATER IN POOR DRAINAGE LOCATIONS.

A WIND ADVISORY IS ALSO IN EFFECT UNTIL 3 AM. SOUTH WINDS OF 25 TO 30
MPH WITH GUSTS OVER 40 MPH WILL CONTINUE AHEAD OF THE LINE OF
THUNDERSTORMS.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY...

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER CALL TO ACTION STATEMENT...

ACTIVATION OF STORM SPOTTERS AND EMERGENCY MANAGEMENT PERSONNEL
IS ONGOING.

In the hours before

Local storm report, Dec 21, 8:46 PM CST, 43 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, Dec 21, 9:21 PM CST, 8 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, Dec 21, 9:29 PM CST, 0 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
Dec 21, 8:08 PM CSTSevere Thunderstorm WarningHUNColbert, Franklin, Lauderdale52 min
Dec 21, 8:55 PM CSTSevere Thunderstorm WarningHUNColbert, Franklin, Lauderdale35 min
Dec 21, 10:08 PM CSTSpecial Weather StatementHUNLawrence37 min
Dec 21, 10:40 PM CSTSpecial Weather StatementHUNLawrence, Limestone50 min
Dec 21, 11:13 PM CSTSpecial Weather StatementHUNLimestone, Morgan47 min
Dec 21, 11:56 PM CSTSpecial Weather StatementHUNMadison, Morgan49 min
Dec 22, 12:36 AM CSTSpecial Weather StatementHUNMadison, Morgan39 min
Dec 22, 1:22 AM CSTFlash Flood WarningHUNMadison3 hr
Dec 22, 1:44 AM CSTSpecial Weather StatementHUNDeKalb, Jackson, Marshall46 min
Dec 22, 2:32 AM CSTSpecial Weather StatementHUNDeKalb43 min
Dec 22, 4:15 AM CSTAreal Flood WarningHUNMadison3 hr
Dec 22, 8:42 AM CSTRiver Flood WarningHUNMadison22 hr
Dec 21, 10:42 PM CSTSpecial Weather StatementHUNLincoln48 min
Dec 21, 11:22 PM CSTSpecial Weather StatementHUNLincoln, Moore38 min

Nearby

Severe Thunderstorm Warnings in Alabama, 2013Every severe thunderstorm warning in 2013

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.