Alert archive / Nebraska / Mesoscale Discussions in 2014

Mesoscale Discussion 520

May 7, 201422 counties in Iowa; 23 counties in Nebraska; Clay County, Union County, South Dakota

The Storm Prediction Center issued this mesoscale discussion at May 7, 2014, 9:44 PM CDT for 22 counties in Iowa; 23 counties in Nebraska; Clay County, Union County, South Dakota. It was in force for 91 min.

The area

The outline as issued.

The facts

Issued
May 7, 2014, 9:44 PM CDT (02:44 UTC)
Expired
May 7, 2014, 11:15 PM CDT
In force
91 min
Issued by
the Storm Prediction Center
All 47 counties

Buena Vista County, IA, Calhoun County, IA, Carroll County, IA, Cherokee County, IA, Clay County, IA, Crawford County, IA, Dickinson County, IA, Emmet County, IA, Harrison County, IA, Humboldt County, IA, Ida County, IA, Kossuth County, IA, Monona County, IA, O'Brien County, IA, Osceola County, IA, Palo Alto County, IA, Plymouth County, IA, Pocahontas County, IA, Sac County, IA, Shelby County, IA, Sioux County, IA, Woodbury County, IA, Antelope County, NE, Boone County, NE, Burt County, NE, Butler County, NE, Cedar County, NE, Colfax County, NE, Cuming County, NE, Dakota County, NE, Dixon County, NE, Dodge County, NE, Douglas County, NE, Madison County, NE, Merrick County, NE, Nance County, NE, Pierce County, NE, Platte County, NE, Polk County, NE, Saunders County, NE, Seward County, NE, Stanton County, NE, Thurston County, NE, Washington County, NE, Wayne County, NE, Clay County, SD, Union County, SD

The radar

The Omaha radar (KOAX), 137 km from the middle of the area, began a volume at 02:46 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

Omaha, NE (KOAX), launched 00:00Z, 2.7 hours before the alert went out and 137 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, Omaha, NE at 00:00Z on 2014-05-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Omaha, NE at 00:00Z on 2014-05-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 68 square meters per square second.19395878Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
4332 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
68 m²/s²
0-3 km storm-relative helicity
53 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

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
May 7, 7:48 PM CDTMesoscale DiscussionSPCAdair, Adams, Audubon, Cass, Fremont, Guthrie and 7 more87 min
May 7, 8:18 PM CDTSevere Thunderstorm WatchSPCFremont, Harrison, Mills, Montgomery, Page, Pottawattamie and 1 more5 hr
May 8, 3:46 AM CDTMesoscale DiscussionSPCClay, Dickinson, Emmet, Lyon, O'Brien, Osceola and 2 more119 min
May 8, 12:23 PM CDTMesoscale DiscussionSPCAdair, Adams, Audubon, Boone, Buena Vista, Butler and 40 more2 hr
May 8, 1:46 PM CDTTornado WatchSPCAdair, Adams, Audubon, Boone, Buena Vista, Calhoun and 45 more7 hr
May 8, 5:56 PM CDTMesoscale DiscussionSPCAdair, Adams, Audubon, Boone, Buena Vista, Calhoun and 42 more94 min
May 7, 7:26 PM CDTSevere Thunderstorm WatchSPCBlaine, Brown, Buffalo, Custer, Dawson, Garfield and 9 more4 hr
May 7, 7:34 PM CDTMesoscale DiscussionSPCArthur, Banner, Chase, Cheyenne, Deuel, Dundy and 10 more56 min

Nearby

Mesoscale Discussions in Nebraska, 2014Mesoscale Discussions in Iowa, 2014Mesoscale Discussions in South Dakota, 2014Every 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.