Alert archive / Wyoming / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 69, NWS Cheyenne, WY

June 27, 1999Converse County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at Jun 27, 1999, 1:41 PM MDT for Converse County, Wyoming. It was in force for 49 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jun 27, 1999, 1:41 PM MDT (19:41 UTC)
Expired: Jun 27, 1999, 2:30 PM MDT
In force: 49 min
Issued by: NWS Cheyenne, WY
Area: Whole counties

County Converse County, WY

The radar

The Cheyenne radar (KCYS), 210 km from the middle of the area, began a volume at 19:40 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

Rapid City, SD (KUNR), launched 12:00Z, 7.7 hours before the alert went out and 244 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: 1202 m above ground
0-6 km bulk shear: 51 kt
0-1 km storm-relative helicity: -11 m²/s²
0-3 km storm-relative helicity: 283 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Cheyenne, WY wrote its last area forecast discussion before this severe thunderstorm warning went out at Jun 27, 1:00 PM MDT, 41 minutes earlier.

Area forecast discussion, Jun 27, 1:00 PM MDT, 41 minutes before

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In the hours before

Local storm report, Jun 27, 8:18 AM MDT, 5 hours 23 minutes before

<!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>

The office that day

Everything else NWS Cheyenne, WY issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 26, 6:26 PM MDT	Tornado Warning	CYS	Banner	34 min
Jun 26, 6:58 PM MDT	Tornado Warning	CYS	Banner, Kimball	32 min
Jun 26, 7:32 PM MDT	Tornado Warning	CYS	Cheyenne	28 min
Jun 26, 7:56 PM MDT	Tornado Warning	CYS	Cheyenne	34 min
Jun 26, 8:26 PM MDT	Tornado Warning	CYS	Cheyenne	34 min
Jun 26, 8:55 PM MDT	Flash Flood Warning	CYS	Cheyenne	5 hr
Jun 26, 9:15 PM MDT	Severe Thunderstorm Warning	CYS	Banner	50 min
Jun 26, 9:47 PM MDT	Severe Thunderstorm Warning	CYS	Banner	33 min
Jun 27, 4:42 PM MDT	Tornado Warning	CYS	Scotts Bluff, Sioux	33 min
Jun 27, 5:39 PM MDT	Tornado Warning	CYS	Scotts Bluff	16 min
Jun 27, 5:41 PM MDT	Severe Thunderstorm Warning	CYS	Morrill	34 min
Jun 26, 6:48 PM MDT	Severe Thunderstorm Warning	CYS	Converse	47 min
Jun 26, 7:05 PM MDT	Severe Thunderstorm Warning	CYS	Platte	40 min
Jun 26, 7:53 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Platte	47 min
Jun 26, 8:31 PM MDT	Severe Thunderstorm Warning	CYS	Platte	49 min
Jun 26, 8:45 PM MDT	Tornado Warning	CYS	Goshen	35 min
Jun 27, 2:08 PM MDT	Severe Thunderstorm Warning	CYS	Niobrara	32 min
Jun 27, 2:59 PM MDT	Severe Thunderstorm Warning	CYS	Platte	36 min
Jun 27, 3:14 PM MDT	Tornado Warning	CYS	Niobrara	31 min
Jun 27, 3:31 PM MDT	Severe Thunderstorm Warning	CYS	Platte	29 min
Jun 27, 3:37 PM MDT	Tornado Warning	CYS	Platte	33 min
Jun 27, 3:51 PM MDT	Severe Thunderstorm Warning	CYS	Goshen	49 min
Jun 27, 4:34 PM MDT	Tornado Warning	CYS	Goshen	21 min

Nearby

Severe Thunderstorm Warnings in Wyoming, 1999 Every severe thunderstorm warning in 1999

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.