Alert archive / Tennessee / Mesoscale Discussions in 2025

Mesoscale Discussion 73

February 6, 202512 counties in Tennessee; Lee County, Virginia

The Storm Prediction Center issued this mesoscale discussion at Feb 6, 2025, 9:28 PM EST for 12 counties in Tennessee; Lee County, Virginia. It was in force for 62 min.

The area

The outline as issued.

The facts

Issued: Feb 6, 2025, 9:28 PM EST (02:28 UTC)
Expired: Feb 6, 2025, 10:30 PM EST
In force: 62 min
Issued by: the Storm Prediction Center
Concerning: Severe thunderstorm watch 4

Counties Anderson County, TN, Claiborne County, TN, Cocke County, TN, Grainger County, TN, Greene County, TN, Hamblen County, TN, Hancock County, TN, Hawkins County, TN, Jefferson County, TN, Knox County, TN, Sevier County, TN, Union County, TN, Lee County, VA

The radar

The Knoxville radar (KMRX), 5 km from the middle of the area, began a volume at 02:33 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 nearest sounding before it

Nashville Metro, TN (KBNA), launched 00:00Z, 2.5 hours before the alert went out and 284 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: 335 J/kg
Mixed-layer CIN: -15 J/kg
Mixed-layer LCL: 651 m above ground
0-6 km bulk shear: 56 kt
0-1 km storm-relative helicity: 248 m²/s²
0-3 km storm-relative helicity: 294 m²/s²
Significant tornado parameter: 0.5
Supercell composite: 3.6

Open this sounding in Storm Lab

The text

As transmitted.

<!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
Feb 6, 7:27 PM EST	Severe Thunderstorm Watch	SPC	Anderson, Blount, Campbell, Claiborne, Cocke, Grainger and 14 more	4 hr
Feb 6, 7:41 PM EST	Mesoscale Discussion	SPC	Anderson, Blount, Campbell, Claiborne, Cocke, Cumberland and 18 more	94 min

Nearby

Mesoscale Discussions in Tennessee, 2025 Mesoscale Discussions in Virginia, 2025 Every mesoscale discussion in 2025

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.