Alert archive / Alabama / Mesoscale Discussions in 2009

Mesoscale Discussion 462

April 13, 20094 states

The Storm Prediction Center issued this mesoscale discussion at Apr 13, 2009, 1:57 AM CDT for 4 states. It was in force for 63 min.

The area

The outline as issued.

The facts

Issued
Apr 13, 2009, 1:57 AM CDT (06:57 UTC)
Expired
Apr 13, 2009, 3:00 AM CDT
In force
63 min
Issued by
the Storm Prediction Center
All 47 counties

Baldwin County, AL, Barbour County, AL, Bullock County, AL, Butler County, AL, Coffee County, AL, Conecuh County, AL, Covington County, AL, Crenshaw County, AL, Dale County, AL, Escambia County, AL, Geneva County, AL, Henry County, AL, Houston County, AL, Macon County, AL, Mobile County, AL, Monroe County, AL, Montgomery County, AL, Pike County, AL, Russell County, AL, Bay County, FL, Calhoun County, FL, Escambia County, FL, Gadsden County, FL, Gulf County, FL, Holmes County, FL, Jackson County, FL, Liberty County, FL, Okaloosa County, FL, Santa Rosa County, FL, Walton County, FL, Washington County, FL, Baker County, GA, Calhoun County, GA, Clay County, GA, Decatur County, GA, Dougherty County, GA, Early County, GA, Miller County, GA, Mitchell County, GA, Quitman County, GA, Randolph County, GA, Seminole County, GA, Stewart County, GA, Terrell County, GA, Webster County, GA, George County, MS, Jackson County, MS

The watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Birmingham, AL (KBMX), launched 00:00Z, 7.0 hours before the alert went out and 214 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 2009-04-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2009-04-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 140 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1755 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
140 m²/s²
0-3 km storm-relative helicity
406 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

<!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>

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 12, 8:07 PM CDTMesoscale DiscussionSPCAutauga, Bibb, Butler, Chilton, Choctaw, Clarke and 12 more53 min
Apr 12, 8:30 PM CDTTornado WatchSPCChoctaw, Clarke, Greene, Hale, Marengo, Mobile and 2 more6 hr
Apr 12, 10:42 PM CDTMesoscale DiscussionSPCAutauga, Baldwin, Barbour, Bibb, Bullock, Butler and 33 more93 min
Apr 12, 11:01 PM CDTTornado WatchSPCAutauga, Baldwin, Butler, Conecuh, Covington, Crenshaw and 8 more4 hr
Apr 13, 2:33 AM CDTTornado WatchSPCBaldwin, Barbour, Bullock, Butler, Clarke, Coffee and 14 more7 hr
Apr 13, 4:32 AM CDTMesoscale DiscussionSPCBaldwin, Barbour, Bullock, Butler, Coffee, Conecuh and 10 more58 min
Apr 13, 7:27 AM CDTMesoscale DiscussionSPCBaldwin, Coffee, Covington, Dale, Escambia, Geneva and 3 more2 hr
Apr 13, 9:12 AM CDTTornado WatchSPCCoffee, Covington, Dale, Escambia, Geneva, Henry and 1 more9 hr
Apr 13, 11:15 AM CDTMesoscale DiscussionSPCBaldwin, Barbour, Bullock, Butler, Clarke, Coffee and 11 more90 min
Apr 13, 12:09 PM CDTMesoscale DiscussionSPCColbert, Franklin, Lauderdale, Lawrence, Limestone, Marion and 2 more66 min
Apr 13, 12:58 PM CDTTornado WatchSPCColbert, Cullman, DeKalb, Franklin, Jackson, Lauderdale and 5 more7 hr
Apr 13, 4:16 PM CDTSevere Thunderstorm WatchSPCChoctaw4 hr
Apr 13, 5:52 PM CDTMesoscale DiscussionSPCBlount, Cullman, DeKalb, Etowah, Fayette, Jackson and 10 more53 min
Apr 13, 6:55 PM CDTMesoscale DiscussionSPCBibb, Chilton, Choctaw, Clarke, Dallas, Greene and 9 more95 min
Apr 13, 11:32 AM CDTTornado WatchSPCBaker, Bradford, Clay, Columbia, Duval, Gilchrist and 5 more6 hr
Apr 13, 5:22 PM CDTMesoscale DiscussionSPCAlachua, Baker, Bradford, Citrus, Clay, Columbia and 18 more83 min
Apr 13, 5:53 PM CDTTornado WatchSPCAlachua, Baker, Bradford, Calhoun, Clay, Columbia and 22 more5 hr
Apr 13, 1:39 PM CDTMesoscale DiscussionSPCAdams, Amite, Copiah, Covington, Forrest, Franklin and 14 more66 min

Nearby

Mesoscale Discussions in Alabama, 2009Mesoscale Discussions in Georgia, 2009Mesoscale Discussions in Florida, 2009Every mesoscale discussion in 2009

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.