Alert archive / Nebraska / Mesoscale Discussions in 2012

Mesoscale Discussion 505

April 12, 201213 counties in Nebraska

The Storm Prediction Center issued this mesoscale discussion at Apr 12, 2012, 8:57 PM CDT for 13 counties in Nebraska. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued: Apr 12, 2012, 8:57 PM CDT (01:57 UTC)
Expired: Apr 12, 2012, 10:30 PM CDT
In force: 93 min
Issued by: the Storm Prediction Center

Counties Blaine County, NE, Buffalo County, NE, Custer County, NE, Dawson County, NE, Franklin County, NE, Furnas County, NE, Gosper County, NE, Harlan County, NE, Kearney County, NE, Lincoln County, NE, Logan County, NE, Phelps County, NE, Sherman County, NE

The radar

The North Platte radar (KLNX), 120 km from the middle of the area, began a volume at 02:00 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

N. Platte/Lee Bi, NE (KLBF), launched 00:00Z, 2.0 hours before the alert went out and 45 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: 188 J/kg
Mixed-layer CIN: -78 J/kg
Mixed-layer LCL: 487 m above ground
0-6 km bulk shear: 53 kt
0-1 km storm-relative helicity: 458 m²/s²
0-3 km storm-relative helicity: 490 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 2.5

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
Apr 12, 7:53 PM CDT	Mesoscale Discussion	SPC	Dundy, Frontier, Hayes, Hitchcock, Red Willow	97 min
Apr 12, 8:38 PM CDT	Severe Thunderstorm Watch	SPC	Frontier, Hayes, Hitchcock, Red Willow	4 hr
Apr 12, 11:24 PM CDT	Mesoscale Discussion	SPC	Buffalo, Dawson, Franklin, Furnas, Gosper, Harlan and 5 more	96 min

Nearby

Mesoscale Discussions in Nebraska, 2012 Every mesoscale discussion in 2012

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.