Alert archive / Illinois / Mesoscale Discussions in 2017
Mesoscale Discussion 1405
The Storm Prediction Center issued this mesoscale discussion at Jul 23, 2017, 3:12 AM CDT for 29 counties in Illinois; 9 counties in Missouri. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 23, 2017, 3:12 AM CDT (08:12 UTC)
- Expired
- Jul 23, 2017, 5:15 AM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
All 38 counties
Bond County, IL, Calhoun County, IL, Christian County, IL, Clay County, IL, Clinton County, IL, Edwards County, IL, Effingham County, IL, Fayette County, IL, Franklin County, IL, Greene County, IL, Hamilton County, IL, Jefferson County, IL, Jersey County, IL, Macoupin County, IL, Madison County, IL, Marion County, IL, Monroe County, IL, Montgomery County, IL, Morgan County, IL, Perry County, IL, Pike County, IL, Randolph County, IL, Richland County, IL, Saint Clair County, IL, Scott County, IL, Shelby County, IL, Washington County, IL, Wayne County, IL, White County, IL, City of Saint Louis, MO, Franklin County, MO, Gasconade County, MO, Jefferson County, MO, Lincoln County, MO, Pike County, MO, Saint Charles County, MO, Saint Louis County, MO, Warren County, MO
The radar
The St Louis radar (KLSX), 71 km from the middle of the area, began a volume at 08:13 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
Lincoln, IL (KILX), launched 00:00Z, 8.2 hours before the alert went out and 184 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
- 2392 J/kg
- Mixed-layer CIN
- -34 J/kg
- Mixed-layer LCL
- 1185 m above ground
- 0-6 km bulk shear
- 26 kt
- 0-1 km storm-relative helicity
- 51 m²/s²
- 0-3 km storm-relative helicity
- 233 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 6.0
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 |
|---|---|---|---|---|
| Jul 22, 7:11 PM CDT | Mesoscale Discussion | SPC | Christian, Clark, Coles, Crawford, Cumberland, Douglas and 10 more | 94 min |
| Jul 22, 11:48 PM CDT | Mesoscale Discussion | SPC | Calhoun, Pike | 87 min |
| Jul 23, 12:38 AM CDT | Severe Thunderstorm Watch | SPC | Adams, Bond, Brown, Calhoun, Cass, Clinton and 13 more | 5 hr |
| Jul 23, 3:32 AM CDT | Severe Thunderstorm Watch | SPC | Christian, Clark, Clay, Coles, Crawford, Cumberland and 14 more | 4 hr |
| Jul 23, 5:23 AM CDT | Mesoscale Discussion | SPC | Clay, Crawford, Edwards, Effingham, Hamilton, Jasper and 5 more | 2 hr |
| Jul 23, 1:03 PM CDT | Mesoscale Discussion | SPC | Boone, Bureau, Champaign, Cook, DeKalb, Douglas and 23 more | 2 hr |
| Jul 22, 9:22 PM CDT | Mesoscale Discussion | SPC | Adair, Andrew, Bates, Boone, Buchanan, Caldwell and 27 more | 113 min |
Nearby
Mesoscale Discussions in Illinois, 2017Mesoscale Discussions in Missouri, 2017Every mesoscale discussion in 2017
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.