Alert archive / Georgia / Mesoscale Discussions in 2007

Mesoscale Discussion 464

April 11, 200722 counties in Georgia; 20 counties in South Carolina

The Storm Prediction Center issued this mesoscale discussion at Apr 11, 2007, 10:43 PM EDT for 22 counties in Georgia; 20 counties in South Carolina. It was in force for 62 min.

The area

The outline as issued.

The facts

Issued: Apr 11, 2007, 10:43 PM EDT (02:43 UTC)
Expired: Apr 11, 2007, 11:45 PM EDT
In force: 62 min
Issued by: the Storm Prediction Center

All 42 counties

Baldwin County, GA, Burke County, GA, Clarke County, GA, Columbia County, GA, Elbert County, GA, Glascock County, GA, Greene County, GA, Hancock County, GA, Hart County, GA, Jefferson County, GA, Lincoln County, GA, Madison County, GA, McDuffie County, GA, Morgan County, GA, Oconee County, GA, Oglethorpe County, GA, Putnam County, GA, Richmond County, GA, Taliaferro County, GA, Warren County, GA, Washington County, GA, Wilkes County, GA, Abbeville County, SC, Aiken County, SC, Anderson County, SC, Bamberg County, SC, Barnwell County, SC, Calhoun County, SC, Chester County, SC, Edgefield County, SC, Fairfield County, SC, Greenwood County, SC, Kershaw County, SC, Laurens County, SC, Lexington County, SC, McCormick County, SC, Newberry County, SC, Orangeburg County, SC, Richland County, SC, Saluda County, SC, Sumter County, SC, Union County, SC

The radar

The Columbia radar (KCAE), 97 km from the middle of the area, began a volume at 02:45 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.

Severe Thunderstorm Watch 128Apr 11, 11:00 PM EDT

The nearest sounding before it

Peachtre/Fal Fld, GA (KFFC), launched 00:00Z, 2.7 hours before the alert went out and 222 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: 365 J/kg
Mixed-layer CIN: -104 J/kg
Mixed-layer LCL: 807 m above ground
0-6 km bulk shear: 77 kt
0-1 km storm-relative helicity: 252 m²/s²
0-3 km storm-relative helicity: 466 m²/s²
Significant tornado parameter: 0.5
Supercell composite: 2.1

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.

Issued	Product	Office	Counties	Lasted
Apr 11, 9:39 PM EDT	Mesoscale Discussion	SPC	Appling, Bryan, Bulloch, Burke, Candler, Chatham and 13 more	96 min
Apr 11, 11:01 PM EDT	Severe Thunderstorm Watch	SPC	Baldwin, Bleckley, Bulloch, Burke, Candler, Columbia and 30 more	6 hr
Apr 12, 4:01 AM EDT	Mesoscale Discussion	SPC	Bryan, Bulloch, Candler, Chatham, Effingham, Evans and 4 more	89 min
Apr 12, 12:16 AM EDT	Mesoscale Discussion	SPC	Dillon, Marlboro	89 min
Apr 12, 12:55 AM EDT	Severe Thunderstorm Watch	SPC	Darlington, Dillon, Florence, Marion, Marlboro	3 hr
Apr 12, 2:39 AM EDT	Mesoscale Discussion	SPC	Dillon	66 min
Apr 12, 3:25 AM EDT	Tornado Watch	SPC	Dillon, Florence, Georgetown, Horry, Marion, Williamsburg	8 hr

Nearby

Mesoscale Discussions in Georgia, 2007 Mesoscale Discussions in South Carolina, 2007 Every mesoscale discussion in 2007

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.