Alert archive / Illinois / Mesoscale Discussions in 2007

Mesoscale Discussion 1692

August 8, 200722 counties in Illinois; Lee County, Van Buren County, Iowa; 7 counties in Missouri

The Storm Prediction Center issued this mesoscale discussion at Aug 8, 2007, 9:16 PM CDT for 22 counties in Illinois; Lee County, Van Buren County, Iowa; 7 counties in Missouri. It was in force for 59 min.

The area

The outline as issued.

The facts

Issued: Aug 8, 2007, 9:16 PM CDT (02:16 UTC)
Expired: Aug 8, 2007, 10:15 PM CDT
In force: 59 min
Issued by: the Storm Prediction Center

All 31 counties

Lee County, IA, Van Buren County, IA, Adams County, IL, Brown County, IL, Cass County, IL, Christian County, IL, DeWitt County, IL, Fulton County, IL, Greene County, IL, Hancock County, IL, Henderson County, IL, Logan County, IL, Macon County, IL, Mason County, IL, McDonough County, IL, Menard County, IL, Morgan County, IL, Moultrie County, IL, Piatt County, IL, Pike County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Tazewell County, IL, Clark County, MO, Knox County, MO, Lewis County, MO, Marion County, MO, Ralls County, MO, Scotland County, MO, Shelby County, MO

The radar

The Lincoln radar (KILX), 101 km from the middle of the area, began a volume at 02:19 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

Davenport, (KDVN), launched 00:00Z, 2.3 hours before the alert went out and 170 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: 194 J/kg
Mixed-layer CIN: -74 J/kg
Mixed-layer LCL: 1146 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 79 m²/s²
0-3 km storm-relative helicity: 158 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.2

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

<!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
Aug 8, 7:06 PM CDT	Mesoscale Discussion	SPC	Appanoose, Davis, Decatur, Fremont, Monroe, Page and 4 more	54 min

Nearby

Mesoscale Discussions in Illinois, 2007 Mesoscale Discussions in Missouri, 2007 Mesoscale Discussions in Iowa, 2007 Every mesoscale discussion in 2007

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.