Alert archive / Mississippi / Mesoscale Discussions in 2009

Mesoscale Discussion 722

May 6, 200920 counties in Arkansas; 23 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at May 6, 2009, 12:53 AM CDT for 20 counties in Arkansas; 23 counties in Mississippi. It was in force for 37 min.

The area

The outline as issued.

The facts

Issued
May 6, 2009, 12:53 AM CDT (05:53 UTC)
Expired
May 6, 2009, 1:30 AM CDT
In force
37 min
Issued by
the Storm Prediction Center
All 43 counties

Arkansas County, AR, Bradley County, AR, Calhoun County, AR, Clark County, AR, Cleveland County, AR, Dallas County, AR, Desha County, AR, Drew County, AR, Grant County, AR, Hempstead County, AR, Hot Spring County, AR, Howard County, AR, Jefferson County, AR, Lafayette County, AR, Lincoln County, AR, Miller County, AR, Nevada County, AR, Ouachita County, AR, Phillips County, AR, Pike County, AR, Bolivar County, MS, Calhoun County, MS, Carroll County, MS, Chickasaw County, MS, Clay County, MS, Coahoma County, MS, Grenada County, MS, Itawamba County, MS, Lafayette County, MS, Lee County, MS, Leflore County, MS, Lowndes County, MS, Monroe County, MS, Montgomery County, MS, Oktibbeha County, MS, Panola County, MS, Pontotoc County, MS, Quitman County, MS, Sunflower County, MS, Tallahatchie County, MS, Union County, MS, Webster County, MS, Yalobusha County, MS

The radar

The Little Rock radar (KLZK), 151 km from the middle of the area, began a volume at 05:55 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

Little Rock, AR (KLZK), launched 00:00Z, 5.9 hours before the alert went out and 183 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, Little Rock, AR at 00:00Z on 2009-05-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3 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, Little Rock, AR at 00:00Z on 2009-05-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 61 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
3 J/kg
Mixed-layer CIN
-164 J/kg
Mixed-layer LCL
617 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
61 m²/s²
0-3 km storm-relative helicity
89 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
May 5, 10:07 PM CDTMesoscale DiscussionSPCArkansas, Calhoun, Clark, Cleveland, Conway, Crittenden and 28 more83 min
May 5, 10:27 PM CDTSevere Thunderstorm WatchSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 49 more8 hr
May 5, 11:26 PM CDTSevere Thunderstorm WatchSPCSebastian6 hr
May 6, 12:54 AM CDTTornado WatchSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 20 more5 hr
May 6, 1:27 AM CDTMesoscale DiscussionSPCArkansas, Clark, Cleveland, Dallas, Desha, Faulkner and 18 more3 hr
May 6, 2:00 AM CDTMesoscale DiscussionSPCSebastian2 hr
May 6, 2:26 AM CDTMesoscale DiscussionSPCCleburne, Conway, Craighead, Crittenden, Cross, Faulkner and 23 more2 hr
May 6, 3:05 AM CDTMesoscale DiscussionSPCAshley, Bradley, Calhoun, Chicot, Clark, Cleveland and 18 more115 min
May 6, 5:29 AM CDTSevere Thunderstorm WatchSPCColumbia, Hempstead, Howard, Lafayette, Little River, Miller and 3 more8 hr
May 6, 5:45 AM CDTSevere Thunderstorm WatchSPCAshley, Bradley, Calhoun, Chicot, Cleveland, Desha and 3 more7 hr
May 6, 6:58 AM CDTMesoscale DiscussionSPCAshley, Bradley, Calhoun, Chicot, Clark, Cleveland and 13 more3 hr
May 6, 7:22 AM CDTMesoscale DiscussionSPCAshley83 min
May 6, 11:34 AM CDTMesoscale DiscussionSPCAdams, Claiborne, Copiah, Covington, Franklin, Hinds and 11 more86 min
May 6, 12:37 PM CDTSevere Thunderstorm WatchSPCAdams, Amite, Claiborne, Clarke, Copiah, Covington and 28 more6 hr

Nearby

Mesoscale Discussions in Mississippi, 2009Mesoscale Discussions in Arkansas, 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.