Alert archive / Iowa / Mesoscale Discussions in 2020

Mesoscale Discussion 1010

June 26, 2020Henderson County, Mercer County, Illinois; 12 counties in Iowa; Scotland County, Missouri

The Storm Prediction Center issued this mesoscale discussion at Jun 26, 2020, 5:40 PM CDT for Henderson County, Mercer County, Illinois; 12 counties in Iowa; Scotland County, Missouri. It was in force for 65 min.

The area

The outline as issued.

The facts

Issued: Jun 26, 2020, 5:40 PM CDT (22:40 UTC)
Expired: Jun 26, 2020, 6:45 PM CDT
In force: 65 min
Issued by: the Storm Prediction Center
Concerning: Severe thunderstorm watch 305

Counties Appanoose County, IA, Davis County, IA, Des Moines County, IA, Henry County, IA, Jefferson County, IA, Keokuk County, IA, Lee County, IA, Louisa County, IA, Muscatine County, IA, Van Buren County, IA, Wapello County, IA, Washington County, IA, Henderson County, IL, Mercer County, IL, Scotland County, MO

The radar

The Quad Cities radar (KDVN), 131 km from the middle of the area, began a volume at 22:41 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 308Jun 26, 7:50 PM CDT

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 10.7 hours before the alert went out and 137 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: 130 J/kg
Mixed-layer CIN: -213 J/kg
Mixed-layer LCL: 1495 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 203 m²/s²
0-3 km storm-relative helicity: 134 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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
Jun 26, 12:38 PM CDT	Mesoscale Discussion	SPC	Boone, Bureau, Carroll, DeKalb, DuPage, Henry and 10 more	2 hr
Jun 26, 1:38 PM CDT	Severe Thunderstorm Watch	SPC	Boone, Bureau, Carroll, Cook, DeKalb, DuPage and 20 more	8 hr
Jun 26, 3:39 PM CDT	Mesoscale Discussion	SPC	Boone, Bureau, Carroll, DeKalb, DuPage, Grundy and 14 more	2 hr
Jun 26, 6:06 PM CDT	Mesoscale Discussion	SPC	Cook, DeKalb, DuPage, Kane, Lake	84 min
Jun 26, 6:30 PM CDT	Mesoscale Discussion	SPC	Adams, Fremont, Mills, Montgomery, Page, Taylor and 1 more	90 min

Nearby

Mesoscale Discussions in Iowa, 2020 Mesoscale Discussions in Illinois, 2020 Mesoscale Discussions in Missouri, 2020 Every 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.