Alert archive / Illinois / Mesoscale Discussions in 2020
Mesoscale Discussion 485
The Storm Prediction Center issued this mesoscale discussion at Apr 28, 2020, 3:33 PM CDT for 47 counties in Illinois; Des Moines County, Lee County, Iowa; 38 counties in Missouri. It was in force for 87 min.
The area
The outline as issued.
The facts
- Issued
- Apr 28, 2020, 3:33 PM CDT (20:33 UTC)
- Expired
- Apr 28, 2020, 5:00 PM CDT
- In force
- 87 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 95%
All 87 counties
Des Moines County, IA, Lee County, IA, Adams County, IL, Bond County, IL, Brown County, IL, Bureau County, IL, Calhoun County, IL, Cass County, IL, Christian County, IL, Clinton County, IL, DeWitt County, IL, Fayette County, IL, Fulton County, IL, Greene County, IL, Hancock County, IL, Henderson County, IL, Henry County, IL, Jersey County, IL, Knox County, IL, LaSalle County, IL, Livingston County, IL, Logan County, IL, Macon County, IL, Macoupin County, IL, Madison County, IL, Marshall County, IL, Mason County, IL, McDonough County, IL, McLean County, IL, Menard County, IL, Mercer County, IL, Monroe County, IL, Montgomery County, IL, Morgan County, IL, Moultrie County, IL, Peoria County, IL, Piatt County, IL, Pike County, IL, Putnam County, IL, Rock Island County, IL, Saint Clair County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Shelby County, IL, Stark County, IL, Tazewell County, IL, Warren County, IL, Woodford County, IL, Audrain County, MO, Benton County, MO, Boone County, MO, Callaway County, MO, Carroll County, MO, Chariton County, MO, City of Saint Louis, MO, Clark County, MO, Cole County, MO, Cooper County, MO, Franklin County, MO, Gasconade County, MO, Henry County, MO, Howard County, MO, Jefferson County, MO, Johnson County, MO, Knox County, MO, Lafayette County, MO, Lewis County, MO, Lincoln County, MO, Macon County, MO, Maries County, MO, Marion County, MO, Miller County, MO, Moniteau County, MO, Monroe County, MO, Montgomery County, MO, Morgan County, MO, Osage County, MO, Pettis County, MO, Pike County, MO, Ralls County, MO, Randolph County, MO, Saint Charles County, MO, Saint Louis County, MO, Saline County, MO, Shelby County, MO, Warren County, MO
The radar
The St Louis radar (KLSX), 88 km from the middle of the area, began a volume at 20:34 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 12:00Z, 8.6 hours before the alert went out and 227 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1609 m above ground
- 0-6 km bulk shear
- 30 kt
- 0-1 km storm-relative helicity
- 159 m²/s²
- 0-3 km storm-relative helicity
- 151 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
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 |
|---|---|---|---|---|
| Apr 28, 3:51 PM CDT | Severe Thunderstorm Watch | SPC | Adams, Bond, Brown, Calhoun, Cass, Christian and 37 more | 7 hr |
| Apr 28, 4:51 PM CDT | Mesoscale Discussion | SPC | Cook, DeKalb, DuPage, Grundy, Kane, Kankakee and 4 more | 114 min |
| Apr 28, 6:32 PM CDT | Mesoscale Discussion | SPC | Bond, Calhoun, Cass, Champaign, Christian, Clinton and 29 more | 118 min |
| Apr 28, 6:41 PM CDT | Mesoscale Discussion | SPC | Alexander, Clay, Edwards, Franklin, Hamilton, Jackson and 12 more | 64 min |
| Apr 28, 1:55 PM CDT | Mesoscale Discussion | SPC | Barry, Barton, Cedar, Dade, Greene, Jasper and 6 more | 3 hr |
| Apr 28, 3:18 PM CDT | Tornado Watch | SPC | Barry, Barton, Jasper, Lawrence, McDonald, Newton and 2 more | 8 hr |
| Apr 28, 6:15 PM CDT | Mesoscale Discussion | SPC | Barry, McDonald, Newton | 2 hr |
Nearby
Mesoscale Discussions in Illinois, 2020Mesoscale Discussions in Missouri, 2020Mesoscale Discussions in Iowa, 2020Every mesoscale discussion in 2020
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.