Alert archive / Iowa / Mesoscale Discussions in 2004

Mesoscale Discussion 571

May 6, 200416 counties in Illinois; 40 counties in Iowa

The Storm Prediction Center issued this mesoscale discussion at May 6, 2004, 11:53 PM CDT for 16 counties in Illinois; 40 counties in Iowa. It was in force for 97 min.

The area

The outline as issued.

The facts

Issued
May 6, 2004, 11:53 PM CDT (04:53 UTC)
Expired
May 7, 2004, 1:30 AM CDT
In force
97 min
Issued by
the Storm Prediction Center
All 56 counties

Adair County, IA, Benton County, IA, Black Hawk County, IA, Boone County, IA, Buchanan County, IA, Cedar County, IA, Clarke County, IA, Clinton County, IA, Dallas County, IA, Delaware County, IA, Des Moines County, IA, Dubuque County, IA, Grundy County, IA, Hardin County, IA, Henry County, IA, Iowa County, IA, Jackson County, IA, Jasper County, IA, Jefferson County, IA, Johnson County, IA, Jones County, IA, Keokuk County, IA, Linn County, IA, Louisa County, IA, Lucas County, IA, Madison County, IA, Mahaska County, IA, Marion County, IA, Marshall County, IA, Monroe County, IA, Muscatine County, IA, Polk County, IA, Poweshiek County, IA, Scott County, IA, Story County, IA, Tama County, IA, Union County, IA, Wapello County, IA, Warren County, IA, Washington County, IA, Bureau County, IL, Carroll County, IL, DeKalb County, IL, Henry County, IL, Jo Daviess County, IL, Knox County, IL, LaSalle County, IL, Lee County, IL, Marshall County, IL, Mercer County, IL, Ogle County, IL, Putnam County, IL, Rock Island County, IL, Stark County, IL, Stephenson County, IL, Whiteside County, IL

The radar

The Quad Cities radar (KDVN), 107 km from the middle of the area, began a volume at 04:57 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, 4.9 hours before the alert went out and 114 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, Davenport, at 00:00Z on 2004-05-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2446 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, Davenport, at 00:00Z on 2004-05-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 113 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
2446 J/kg
Mixed-layer CIN
-45 J/kg
Mixed-layer LCL
1583 m above ground
0-6 km bulk shear
48 kt
0-1 km storm-relative helicity
113 m²/s²
0-3 km storm-relative helicity
217 m²/s²
Significant tornado parameter
0.8
Supercell composite
9.0

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 7, 4:24 AM CDTMesoscale DiscussionSPCBoone, Bureau, Carroll, Cook, DeKalb, DuPage and 22 more96 min
May 7, 5:00 AM CDTSevere Thunderstorm WatchSPCBureau, Ford, Grundy, Iroquois, Kankakee, Kendall and 10 more4 hr
May 7, 6:38 AM CDTMesoscale DiscussionSPCBureau, Champaign, DeWitt, Ford, Grundy, Iroquois and 12 more97 min
May 7, 11:44 AM CDTMesoscale DiscussionSPCBureau, Carroll, DeKalb, DuPage, Grundy, Henry and 9 more2 hr
May 7, 4:33 PM CDTMesoscale DiscussionSPCBoone, Carroll, Cook, DeKalb, DuPage, Jo Daviess and 9 more87 min
May 7, 5:25 PM CDTSevere Thunderstorm WatchSPCBoone, Carroll, Cook, DeKalb, DuPage, Jo Daviess and 6 more6 hr
May 7, 2:26 PM CDTMesoscale DiscussionSPCAdair, Adams, Audubon, Buena Vista, Calhoun, Carroll and 26 more3 hr

Nearby

Mesoscale Discussions in Iowa, 2004Mesoscale Discussions in Illinois, 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; radar from the NEXRAD Level II archive.