Alert archive / Michigan / Mesoscale Discussions in 2011

Mesoscale Discussion 1780

July 29, 20115 states

The Storm Prediction Center issued this mesoscale discussion at Jul 29, 2011, 3:31 AM EDT for 5 states. It was in force for 89 min.

The area

The outline as issued.

The facts

Issued: Jul 29, 2011, 3:31 AM EDT (07:31 UTC)
Expired: Jul 29, 2011, 5:00 AM EDT
In force: 89 min
Issued by: the Storm Prediction Center

All 31 counties

DeKalb County, IN, Elkhart County, IN, LaGrange County, IN, Steuben County, IN, Branch County, MI, Calhoun County, MI, Cass County, MI, Hillsdale County, MI, Jackson County, MI, Kalamazoo County, MI, Lenawee County, MI, Macomb County, MI, Monroe County, MI, Saint Joseph County, MI, Washtenaw County, MI, Wayne County, MI, Allegany County, NY, Cattaraugus County, NY, Chautauqua County, NY, Erie County, NY, Wyoming County, NY, Ashtabula County, OH, Fulton County, OH, Lake County, OH, Lucas County, OH, Ottawa County, OH, Williams County, OH, Crawford County, PA, Erie County, PA, McKean County, PA, Warren County, PA

The radar

The Cleveland radar (KCLE), 95 km from the middle of the area, began a volume at 07:34 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.

Severe Thunderstorm Watch 698Jul 29, 3:50 AM EDT

The nearest sounding before it

Detroit, MI (KDTX), launched 00:00Z, 7.5 hours before the alert went out and 103 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: 2191 J/kg
Mixed-layer CIN: -1 J/kg
Mixed-layer LCL: 825 m above ground
0-6 km bulk shear: 33 kt
0-1 km storm-relative helicity: 87 m²/s²
0-3 km storm-relative helicity: 99 m²/s²
Significant tornado parameter: 0.7
Supercell composite: 3.4

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
Jul 29, 12:51 AM EDT	Mesoscale Discussion	SPC	Elkhart, Lake, LaPorte, Porter, Saint Joseph	84 min
Jul 29, 2:15 AM EDT	Severe Thunderstorm Watch	SPC	Elkhart, LaGrange, LaPorte, Saint Joseph, Steuben	6 hr
Jul 29, 4:51 PM EDT	Mesoscale Discussion	SPC	Bartholomew, Blackford, Boone, Brown, Clay, Clinton and 31 more	84 min
Jul 29, 3:56 AM EDT	Severe Thunderstorm Watch	SPC	Allegany, Cattaraugus, Chautauqua, Erie, Genesee, Livingston and 1 more	5 hr
Jul 29, 12:57 PM EDT	Mesoscale Discussion	SPC	Albany, Broome, Chemung, Chenango, Cortland, Delaware and 15 more	2 hr
Jul 29, 2:40 PM EDT	Severe Thunderstorm Watch	SPC	Bronx, Broome, Chemung, Chenango, Columbia, Cortland and 16 more	8 hr
Jul 29, 4:40 PM EDT	Mesoscale Discussion	SPC	Bronx, Broome, Chemung, Chenango, Columbia, Delaware and 16 more	95 min
Jul 29, 5:03 PM EDT	Tornado Watch	SPC	Orange, Putnam, Rockland, Westchester	3 hr
Jul 29, 2:06 PM EDT	Mesoscale Discussion	SPC	Ashland, Belmont, Carroll, Champaign, Clark, Columbiana and 35 more	84 min

Nearby

Mesoscale Discussions in Michigan, 2011 Mesoscale Discussions in Ohio, 2011 Mesoscale Discussions in New York, 2011 Every mesoscale discussion in 2011

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.