Alert archive / Illinois / Mesoscale Discussions in 2014

Mesoscale Discussion 1040

June 17, 201417 counties in Illinois; 15 counties in Indiana

The Storm Prediction Center issued this mesoscale discussion at Jun 17, 2014, 1:58 PM CDT for 17 counties in Illinois; 15 counties in Indiana. It was in force for 92 min.

The area

The outline as issued.

The facts

Issued: Jun 17, 2014, 1:58 PM CDT (18:58 UTC)
Expired: Jun 17, 2014, 3:30 PM CDT
In force: 92 min
Issued by: the Storm Prediction Center
Chance of a watch: 40%

All 32 counties

Bureau County, IL, Grundy County, IL, Henry County, IL, Iroquois County, IL, Kankakee County, IL, Kendall County, IL, Knox County, IL, LaSalle County, IL, Lee County, IL, Livingston County, IL, Marshall County, IL, Peoria County, IL, Putnam County, IL, Stark County, IL, Whiteside County, IL, Will County, IL, Woodford County, IL, DeKalb County, IN, Elkhart County, IN, Fulton County, IN, Jasper County, IN, Kosciusko County, IN, LaGrange County, IN, Lake County, IN, LaPorte County, IN, Marshall County, IN, Newton County, IN, Noble County, IN, Porter County, IN, Pulaski County, IN, Starke County, IN, Whitley County, IN

The radar

The Chicago radar (KLOT), 60 km from the middle of the area, began a volume at 19:00 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

Lincoln, IL (KILX), launched 12:00Z, 7.0 hours before the alert went out and 161 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: 1334 J/kg
Mixed-layer CIN: -189 J/kg
Mixed-layer LCL: 833 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 292 m²/s²
0-3 km storm-relative helicity: 305 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 2.8

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
Jun 16, 9:01 PM CDT	Severe Thunderstorm Watch	SPC	Bureau, Carroll, Henderson, Henry, Jo Daviess, Mercer and 5 more	8 hr
Jun 16, 9:24 PM CDT	Severe Thunderstorm Watch	SPC	Boone, DeKalb, Kane, LaSalle, Lee, McHenry and 2 more	6 hr
Jun 16, 11:40 PM CDT	Mesoscale Discussion	SPC	Boone, Bureau, Carroll, DeKalb, Grundy, Henry and 12 more	65 min
Jun 17, 1:29 AM CDT	Mesoscale Discussion	SPC	Boone, Bureau, DeKalb, Henderson, Henry, Kane and 11 more	91 min
Jun 17, 3:41 AM CDT	Mesoscale Discussion	SPC	Boone, Bureau, Carroll, Cook, DeKalb, DuPage and 19 more	64 min
Jun 17, 4:11 AM CDT	Tornado Watch	SPC	Boone, Bureau, Carroll, Cook, DeKalb, DuPage and 16 more	3 hr
Jun 17, 4:58 AM CDT	Mesoscale Discussion	SPC	Boone, Cook, DuPage, Kane, Lake, McHenry	62 min

Nearby

Mesoscale Discussions in Illinois, 2014 Mesoscale Discussions in Indiana, 2014 Every mesoscale discussion in 2014

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.