Alert archive / Tennessee / Mesoscale Discussions in 2018
Mesoscale Discussion 814
The Storm Prediction Center issued this mesoscale discussion at Jun 21, 2018, 5:44 PM CDT for 6 states. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Jun 21, 2018, 5:44 PM CDT (22:44 UTC)
- Expired
- Jun 21, 2018, 7:45 PM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
All 60 counties
Colbert County, AL, Massac County, IL, Ballard County, KY, Caldwell County, KY, Calloway County, KY, Carlisle County, KY, Christian County, KY, Crittenden County, KY, Fulton County, KY, Graves County, KY, Hickman County, KY, Hopkins County, KY, Livingston County, KY, Logan County, KY, Lyon County, KY, Marshall County, KY, McCracken County, KY, Muhlenberg County, KY, Todd County, KY, Trigg County, KY, Mississippi County, MO, Alcorn County, MS, Benton County, MS, DeSoto County, MS, Marshall County, MS, Prentiss County, MS, Tippah County, MS, Tishomingo County, MS, Benton County, TN, Carroll County, TN, Cheatham County, TN, Chester County, TN, Crockett County, TN, Decatur County, TN, Dickson County, TN, Dyer County, TN, Fayette County, TN, Gibson County, TN, Hardeman County, TN, Hardin County, TN, Haywood County, TN, Henderson County, TN, Henry County, TN, Hickman County, TN, Houston County, TN, Humphreys County, TN, Lake County, TN, Lauderdale County, TN, Lewis County, TN, Madison County, TN, McNairy County, TN, Montgomery County, TN, Obion County, TN, Perry County, TN, Robertson County, TN, Shelby County, TN, Stewart County, TN, Tipton County, TN, Wayne County, TN, Weakley County, TN
The radar
The Paducah radar (KPAH), 111 km from the middle of the area, began a volume at 22:45 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 nearest sounding before it
Little Rock, AR (KBYH), launched 12:00Z, 10.7 hours before the alert went out and 194 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.
- Mixed-layer CAPE
- 399 J/kg
- Mixed-layer CIN
- -64 J/kg
- Mixed-layer LCL
- 736 m above ground
- 0-6 km bulk shear
- 27 kt
- 0-1 km storm-relative helicity
- 79 m²/s²
- 0-3 km storm-relative helicity
- 64 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 0.8
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 |
|---|---|---|---|---|
| Jun 21, 2:29 PM CDT | Mesoscale Discussion | SPC | Chambers, Lee, Macon, Randolph, Tallapoosa | 91 min |
| Jun 21, 12:31 PM CDT | Mesoscale Discussion | SPC | Alexander, Franklin, Gallatin, Hardin, Jackson, Johnson and 6 more | 2 hr |
| Jun 21, 1:39 PM CDT | Severe Thunderstorm Watch | SPC | Alexander, Hardin, Johnson, Massac, Pope, Pulaski and 1 more | 7 hr |
| Jun 21, 1:53 PM CDT | Mesoscale Discussion | SPC | Henry, Knox, Marshall, Peoria, Rock Island, Stark and 2 more | 3 hr |
| Jun 21, 3:56 PM CDT | Mesoscale Discussion | SPC | Alexander, Hardin, Johnson, Massac, Pope, Pulaski and 1 more | 2 hr |
Nearby
Mesoscale Discussions in Tennessee, 2018Mesoscale Discussions in Kentucky, 2018Mesoscale Discussions in Mississippi, 2018Every mesoscale discussion in 2018
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.