Alert archive / Ohio / Mesoscale Discussions in 2020

Mesoscale Discussion 1683

September 7, 20204 counties in Illinois; 13 counties in Indiana; 15 counties in Ohio

The Storm Prediction Center issued this mesoscale discussion at Sep 7, 2020, 3:59 PM CDT for 4 counties in Illinois; 13 counties in Indiana; 15 counties in Ohio. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Sep 7, 2020, 3:59 PM CDT (20:59 UTC)
Expired: Sep 7, 2020, 6:00 PM CDT
In force: 2 hr
Issued by: the Storm Prediction Center
Concerning: Severe potential...watch unlikely
Chance of a watch: 20%

All 32 counties

Coles County, IL, Douglas County, IL, Edgar County, IL, Moultrie County, IL, Boone County, IN, Hamilton County, IN, Hancock County, IN, Hendricks County, IN, Henry County, IN, Madison County, IN, Marion County, IN, Parke County, IN, Putnam County, IN, Randolph County, IN, Vermillion County, IN, Vigo County, IN, Wayne County, IN, Champaign County, OH, Clark County, OH, Coshocton County, OH, Darke County, OH, Delaware County, OH, Franklin County, OH, Holmes County, OH, Knox County, OH, Licking County, OH, Madison County, OH, Miami County, OH, Morrow County, OH, Preble County, OH, Tuscarawas County, OH, Union County, OH

The radar

The Cincinnati radar (KILN), 86 km from the middle of the area, began a volume at 21:01 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

Cncnati-Daytn, OH (KILN), launched 12:00Z, 9.0 hours before the alert went out and 86 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1756 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 185 m²/s²
0-3 km storm-relative helicity: 195 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

<!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
Sep 6, 9:32 PM CDT	Mesoscale Discussion	SPC	Boone, Bureau, Carroll, Cook, DeKalb, DuPage and 13 more	118 min

Nearby

Mesoscale Discussions in Ohio, 2020 Mesoscale Discussions in Indiana, 2020 Mesoscale Discussions in Illinois, 2020 Every mesoscale discussion in 2020

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.