Alert archive / Missouri / Mesoscale Discussions in 2015

Mesoscale Discussion 1396

July 13, 201520 counties in Illinois; 38 counties in Missouri

The Storm Prediction Center issued this mesoscale discussion at Jul 13, 2015, 4:33 PM CDT for 20 counties in Illinois; 38 counties in Missouri. It was in force for 57 min.

The area

The outline as issued.

The facts

Issued
Jul 13, 2015, 4:33 PM CDT (21:33 UTC)
Expired
Jul 13, 2015, 5:30 PM CDT
In force
57 min
Issued by
the Storm Prediction Center
Chance of a watch
60%
All 58 counties

Adams County, IL, Bond County, IL, Brown County, IL, Calhoun County, IL, Christian County, IL, Clinton County, IL, Fayette County, IL, Greene County, IL, Jersey County, IL, Macoupin County, IL, Madison County, IL, Monroe County, IL, Montgomery County, IL, Morgan County, IL, Pike County, IL, Randolph County, IL, Saint Clair County, IL, Sangamon County, IL, Scott County, IL, Washington County, IL, Adair County, MO, Audrain County, MO, Boone County, MO, Callaway County, MO, Carroll County, MO, Chariton County, MO, City of Saint Louis, MO, Cole County, MO, Cooper County, MO, Franklin County, MO, Gasconade County, MO, Grundy County, MO, Howard County, MO, Jefferson County, MO, Knox County, MO, Lewis County, MO, Lincoln County, MO, Linn County, MO, Livingston County, MO, Macon County, MO, Marion County, MO, Mercer County, MO, Moniteau County, MO, Monroe County, MO, Montgomery County, MO, Osage County, MO, Perry County, MO, Pike County, MO, Ralls County, MO, Randolph County, MO, Saint Charles County, MO, Saint Louis County, MO, Sainte Genevieve County, MO, Saline County, MO, Shelby County, MO, Sullivan County, MO, Warren County, MO, Washington County, MO

The radar

The St Louis radar (KLSX), 128 km from the middle of the area, began a volume at 21:36 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

Davenport, (KDVN), launched 12:00Z, 9.6 hours before the alert went out and 280 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 12:00Z on 2015-07-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3490 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 12:00Z on 2015-07-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 86 square meters per square second.1939587897Sfc1 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
3490 J/kg
Mixed-layer CIN
-51 J/kg
Mixed-layer LCL
832 m above ground
0-6 km bulk shear
55 kt
0-1 km storm-relative helicity
86 m²/s²
0-3 km storm-relative helicity
83 m²/s²
Significant tornado parameter
1.7
Supercell composite
6.3

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
Jul 13, 3:49 AM CDTMesoscale DiscussionSPCBoone, Cook, DeKalb, DuPage, Grundy, Iroquois and 7 more116 min
Jul 13, 4:14 AM CDTSevere Thunderstorm WatchSPCBoone, Bureau, Carroll, Cook, DeKalb, DuPage and 18 more6 hr
Jul 13, 7:19 AM CDTMesoscale DiscussionSPCFord, Grundy, Iroquois, Kankakee, Kendall, LaSalle and 2 more86 min
Jul 13, 9:17 AM CDTSevere Thunderstorm WatchSPCChampaign, Clark, Coles, Crawford, Cumberland, DeWitt and 16 more4 hr
Jul 13, 11:01 AM CDTMesoscale DiscussionSPCEdwards, Wabash, White89 min
Jul 13, 3:21 PM CDTMesoscale DiscussionSPCBoone, Bureau, Carroll, Champaign, DeKalb, DeWitt and 29 more84 min
Jul 13, 4:01 PM CDTTornado WatchSPCBoone, Bureau, Carroll, Cass, Champaign, Christian and 52 more7 hr
Jul 13, 6:20 PM CDTSevere Thunderstorm WatchSPCAdams, Bond, Brown, Calhoun, Clinton, Fayette and 11 more4 hr
Jul 13, 6:59 PM CDTMesoscale DiscussionSPCBoone, Brown, Bureau, Carroll, Cass, Champaign and 65 more91 min

Nearby

Mesoscale Discussions in Missouri, 2015Mesoscale Discussions in Illinois, 2015Every mesoscale discussion in 2015

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.