Alert archive / Tennessee / Mesoscale Discussions in 2009

Mesoscale Discussion 429

April 10, 20094 states

The Storm Prediction Center issued this mesoscale discussion at Apr 10, 2009, 11:14 AM CDT for 4 states. It was in force for 76 min.

The area

The outline as issued.

The facts

Issued
Apr 10, 2009, 11:14 AM CDT (16:14 UTC)
Expired
Apr 10, 2009, 12:30 PM CDT
In force
76 min
Issued by
the Storm Prediction Center
Concerning
Tornado watch 131
All 64 counties

Colbert County, AL, Franklin County, AL, Jackson County, AL, Lauderdale County, AL, Lawrence County, AL, Limestone County, AL, Madison County, AL, Marion County, AL, Morgan County, AL, Winston County, AL, Allen County, KY, Calloway County, KY, Christian County, KY, Logan County, KY, Lyon County, KY, Marshall County, KY, Simpson County, KY, Todd County, KY, Trigg County, KY, Warren County, KY, Alcorn County, MS, Benton County, MS, Itawamba County, MS, Prentiss County, MS, Tippah County, MS, Tishomingo County, MS, Union County, MS, Bedford County, TN, Benton County, TN, Cannon County, TN, Carroll County, TN, Cheatham County, TN, Chester County, TN, Coffee County, TN, Davidson County, TN, Decatur County, TN, Dickson County, TN, Franklin County, TN, Giles County, TN, Hardeman County, TN, Hardin County, TN, Henderson County, TN, Henry County, TN, Hickman County, TN, Houston County, TN, Humphreys County, TN, Lawrence County, TN, Lewis County, TN, Lincoln County, TN, Madison County, TN, Marshall County, TN, Maury County, TN, McNairy County, TN, Montgomery County, TN, Moore County, TN, Perry County, TN, Robertson County, TN, Rutherford County, TN, Stewart County, TN, Sumner County, TN, Trousdale County, TN, Wayne County, TN, Williamson County, TN, Wilson County, TN

The radar

The Nashville radar (KOHX), 84 km from the middle of the area, began a volume at 16:18 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 watches that followed

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

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 12:00Z, 4.2 hours before the alert went out and 73 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, Nashville Metro, TN at 12:00Z on 2009-04-10Temperature 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, Nashville Metro, TN at 12:00Z on 2009-04-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -50 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1414 m above ground
0-6 km bulk shear
71 kt
0-1 km storm-relative helicity
-50 m²/s²
0-3 km storm-relative helicity
-4 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 10, 1:24 AM CDTMesoscale DiscussionSPCColbert, Fayette, Franklin, Lamar, Lauderdale, Marion and 1 more96 min
Apr 10, 1:43 AM CDTTornado WatchSPCBlount, Colbert, Cullman, Fayette, Franklin, Greene and 12 more5 hr
Apr 10, 4:25 AM CDTMesoscale DiscussionSPCBlount, Calhoun, Cherokee, Cleburne, Cullman, DeKalb and 13 more95 min
Apr 10, 8:22 AM CDTMesoscale DiscussionSPCLauderdale83 min
Apr 10, 11:23 AM CDTTornado Watch PDSSPCBibb, Blount, Calhoun, Cherokee, Cleburne, Colbert and 25 more8 hr
Apr 10, 12:58 PM CDTMesoscale DiscussionSPCColbert, Cullman, Fayette, Franklin, Jackson, Lamar and 8 more92 min
Apr 10, 2:29 PM CDTMesoscale DiscussionSPCCleburne91 min
Apr 10, 2:39 PM CDTTornado Watch PDSSPCAutauga, Barbour, Bullock, Calhoun, Chambers, Cherokee and 19 more8 hr
Apr 10, 3:43 PM CDTMesoscale DiscussionSPCBlount, Calhoun, Cherokee, Cleburne, DeKalb, Etowah and 4 more92 min
Apr 10, 6:34 PM CDTMesoscale DiscussionSPCAutauga, Calhoun, Chambers, Chilton, Clay, Cleburne and 9 more56 min
Apr 9, 10:52 PM CDTSevere Thunderstorm WatchSPCBallard, Calloway, Carlisle, Crittenden, Fulton, Graves and 5 more4 hr
Apr 10, 12:50 AM CDTMesoscale DiscussionSPCBallard, Breckinridge, Butler, Caldwell, Calloway, Carlisle and 26 more85 min
Apr 10, 1:22 AM CDTSevere Thunderstorm WatchSPCAllen, Barren, Breckinridge, Bullitt, Butler, Caldwell and 23 more4 hr
Apr 10, 3:33 AM CDTMesoscale DiscussionSPCAdair, Allen, Barren, Breckinridge, Bullitt, Butler and 28 more57 min
Apr 10, 8:53 AM CDTTornado WatchSPCAdair, Allen, Anderson, Barren, Bourbon, Boyle and 64 more7 hr
Apr 10, 10:30 AM CDTMesoscale DiscussionSPCAnderson, Bourbon, Boyle, Breckinridge, Bullitt, Clark and 14 more60 min
Apr 10, 1:26 PM CDTMesoscale DiscussionSPCAdair, Allen, Anderson, Barren, Bath, Bell and 87 more64 min
Apr 10, 1:51 PM CDTTornado WatchSPCBath, Bell, Breathitt, Clay, Elliott, Estill and 27 more6 hr
Apr 10, 2:56 PM CDTMesoscale DiscussionSPCBreathitt, Clark, Elliott, Estill, Floyd, Jackson and 12 more64 min
Apr 10, 3:06 PM CDTMesoscale DiscussionSPCAdair, Allen, Barren, Breckinridge, Bullitt, Edmonson and 15 more54 min
Apr 10, 3:42 PM CDTMesoscale DiscussionSPCBreathitt, Clay, Elliott, Floyd, Harlan, Johnson and 14 more63 min
Apr 10, 6:53 PM CDTMesoscale DiscussionSPCHarlan, Letcher67 min
Apr 9, 10:48 PM CDTTornado WatchSPCBolivar, Carroll, Coahoma, DeSoto, Grenada, Holmes and 17 more4 hr

Nearby

Mesoscale Discussions in Tennessee, 2009Mesoscale Discussions in Alabama, 2009Mesoscale Discussions in Kentucky, 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; radar from the NEXRAD Level II archive.