Alert archive / Illinois / Mesoscale Discussions in 2004

Mesoscale Discussion 817

May 22, 200419 counties in Illinois; 12 counties in Iowa; 17 counties in Missouri

The Storm Prediction Center issued this mesoscale discussion at May 22, 2004, 6:58 AM CDT for 19 counties in Illinois; 12 counties in Iowa; 17 counties in Missouri. It was in force for 62 min.

The area

The outline as issued.

The facts

Issued
May 22, 2004, 6:58 AM CDT (11:58 UTC)
Expired
May 22, 2004, 8:00 AM CDT
In force
62 min
Issued by
the Storm Prediction Center
All 48 counties

Appanoose County, IA, Davis County, IA, Decatur County, IA, Des Moines County, IA, Henry County, IA, Jefferson County, IA, Lee County, IA, Lucas County, IA, Monroe County, IA, Van Buren County, IA, Wapello County, IA, Wayne County, IA, Adams County, IL, Brown County, IL, Cass County, IL, Fulton County, IL, Hancock County, IL, Henderson County, IL, Knox County, IL, Logan County, IL, Marshall County, IL, Mason County, IL, McDonough County, IL, Menard County, IL, Morgan County, IL, Peoria County, IL, Schuyler County, IL, Stark County, IL, Tazewell County, IL, Warren County, IL, Woodford County, IL, Adair County, MO, Clark County, MO, Daviess County, MO, Grundy County, MO, Harrison County, MO, Knox County, MO, Lewis County, MO, Linn County, MO, Livingston County, MO, Macon County, MO, Marion County, MO, Mercer County, MO, Putnam County, MO, Schuyler County, MO, Scotland County, MO, Shelby County, MO, Sullivan County, MO

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 12.0 hours before the alert went out and 271 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-pSkew-T log-p diagram, Lincoln, IL at 00:00Z on 2004-05-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1120 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lincoln, IL at 00:00Z on 2004-05-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 50 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
1120 J/kg
Mixed-layer CIN
-86 J/kg
Mixed-layer LCL
1669 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
50 m²/s²
0-3 km storm-relative helicity
144 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.1

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.

IssuedProductOfficeCountiesLasted
May 21, 7:37 PM CDTMesoscale DiscussionSPCBoone, Bureau, Carroll, DeKalb, DuPage, Grundy and 19 more83 min
May 22, 12:05 AM CDTSevere Thunderstorm WatchSPCBoone, Bureau, Carroll, Cook, DeKalb, DuPage and 22 more6 hr
May 22, 2:41 AM CDTMesoscale DiscussionSPCBoone, Bureau, Carroll, Cook, DeKalb, DuPage and 23 more94 min
May 22, 11:03 AM CDTMesoscale DiscussionSPCDeWitt, Ford, Grundy, Iroquois, Kankakee, LaSalle and 9 more57 min
May 22, 11:35 AM CDTSevere Thunderstorm WatchSPCChampaign, Cook, DeWitt, Douglas, Ford, Grundy and 10 more6 hr
May 22, 5:52 PM CDTMesoscale DiscussionSPCBureau, Carroll, DeKalb, Grundy, Henry, Jo Daviess and 12 more113 min
May 22, 6:15 PM CDTTornado WatchSPCBoone, Bureau, Carroll, DeKalb, DuPage, Grundy and 25 more6 hr
May 21, 9:55 PM CDTTornado WatchSPCAudubon, Boone, Buena Vista, Calhoun, Carroll, Cherokee and 14 more4 hr
May 22, 12:25 AM CDTMesoscale DiscussionSPCAudubon, Boone, Buena Vista, Calhoun, Carroll, Cherokee and 14 more2 hr
May 22, 12:55 AM CDTSevere Thunderstorm WatchSPCAdair, Adams, Audubon, Boone, Carroll, Cass and 17 more5 hr
May 22, 3:44 AM CDTMesoscale DiscussionSPCAdair, Adams, Audubon, Boone, Cass, Dallas and 11 more61 min
May 22, 3:02 PM CDTMesoscale DiscussionSPCAdair, Adams, Appanoose, Audubon, Cass, Clarke and 29 more58 min
May 22, 3:45 PM CDTTornado WatchSPCFremont, Harrison, Mills, Pottawattamie, Shelby7 hr

Nearby

Mesoscale Discussions in Illinois, 2004Mesoscale Discussions in Missouri, 2004Mesoscale Discussions in Iowa, 2004Every mesoscale discussion in 2004

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.