Alert archive / Nebraska / Mesoscale Discussions in 2007

Mesoscale Discussion 1832

August 21, 20074 counties in Kansas; 50 counties in Nebraska; 6 counties in South Dakota

The Storm Prediction Center issued this mesoscale discussion at Aug 21, 2007, 2:47 PM CDT for 4 counties in Kansas; 50 counties in Nebraska; 6 counties in South Dakota. It was in force for 118 min.

The area

The outline as issued.

The facts

Issued
Aug 21, 2007, 2:47 PM CDT (19:47 UTC)
Expired
Aug 21, 2007, 4:45 PM CDT
In force
118 min
Issued by
the Storm Prediction Center
All 60 counties

Cheyenne County, KS, Decatur County, KS, Rawlins County, KS, Sherman County, KS, Antelope County, NE, Blaine County, NE, Boone County, NE, Boyd County, NE, Brown County, NE, Buffalo County, NE, Burt County, NE, Cedar County, NE, Chase County, NE, Colfax County, NE, Cuming County, NE, Custer County, NE, Dakota County, NE, Dawson County, NE, Dixon County, NE, Dodge County, NE, Dundy County, NE, Frontier County, NE, Furnas County, NE, Garfield County, NE, Gosper County, NE, Greeley County, NE, Hall County, NE, Hamilton County, NE, Harlan County, NE, Hayes County, NE, Hitchcock County, NE, Holt County, NE, Howard County, NE, Kearney County, NE, Keya Paha County, NE, Knox County, NE, Lincoln County, NE, Logan County, NE, Loup County, NE, Madison County, NE, Merrick County, NE, Nance County, NE, Phelps County, NE, Pierce County, NE, Platte County, NE, Polk County, NE, Red Willow County, NE, Rock County, NE, Sherman County, NE, Stanton County, NE, Thurston County, NE, Valley County, NE, Wayne County, NE, Wheeler County, NE, Bon Homme County, SD, Charles Mix County, SD, Douglas County, SD, Gregory County, SD, Tripp County, SD, Yankton County, SD

The radar

The North Platte radar (KLNX), 97 km from the middle of the area, began a volume at 19:49 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.

The nearest sounding before it

N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 7.8 hours before the alert went out and 100 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, N. Platte/Lee Bi, NE at 12:00Z on 2007-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2298 joules per kilogram.LCLLFCEL10008507005003002001001 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, N. Platte/Lee Bi, NE at 12:00Z on 2007-08-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 82 square meters per square second.193958Sfc1 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
2298 J/kg
Mixed-layer CIN
-210 J/kg
Mixed-layer LCL
1059 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
82 m²/s²
0-3 km storm-relative helicity
168 m²/s²
Significant tornado parameter
0.0
Supercell composite
-1.6

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
Aug 20, 8:01 PM CDTMesoscale DiscussionSPCBarber, Clark, Comanche, Edwards, Finney, Ford and 15 more89 min
Aug 20, 9:13 PM CDTMesoscale DiscussionSPCBarber, Barton, Butler, Chase, Clark, Coffey and 40 more32 min
Aug 20, 9:45 PM CDTSevere Thunderstorm WatchSPCBarber, Barton, Butler, Chase, Clark, Comanche and 25 more3 hr
Aug 20, 11:11 PM CDTMesoscale DiscussionSPCBarber, Harper, Kingman64 min
Aug 21, 3:50 PM CDTSevere Thunderstorm WatchSPCCheyenne, Decatur, Gove, Graham, Greeley, Logan and 8 more6 hr
Aug 21, 5:53 PM CDTMesoscale DiscussionSPCDecatur, Greeley, Logan, Norton, Rawlins, Sheridan and 3 more97 min
Aug 20, 7:03 PM CDTMesoscale DiscussionSPCCedar117 min
Aug 20, 7:35 PM CDTMesoscale DiscussionSPCBurt, Butler, Cass, Clay, Colfax, Cuming and 27 more85 min
Aug 21, 3:45 PM CDTTornado WatchSPCAntelope, Boone, Boyd, Cedar, Colfax, Cuming and 14 more6 hr
Aug 21, 6:17 PM CDTMesoscale DiscussionSPCAntelope, Boone, Burt, Cedar, Colfax, Cuming and 11 more88 min
Aug 21, 6:47 PM CDTTornado WatchSPCBurt, Dodge, Washington7 hr

Nearby

Mesoscale Discussions in Nebraska, 2007Mesoscale Discussions in South Dakota, 2007Mesoscale Discussions in Kansas, 2007Every mesoscale discussion in 2007

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.