Alert archive / Wyoming / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 32, NWS Cheyenne, WY

June 12, 1999Laramie County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at Jun 12, 1999, 1:52 PM MDT for Laramie County, Wyoming. It was in force for 48 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 12, 1999, 1:52 PM MDT (19:52 UTC)
Expired: Jun 12, 1999, 2:40 PM MDT
In force: 48 min
Issued by: NWS Cheyenne, WY
Area: Whole counties

County Laramie County, WY

The radar

The Cheyenne radar (KCYS), 20 km from the middle of the area, began a volume at 19:51 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

Denver, CO (KDNR), launched 12:00Z, 7.9 hours before the alert went out and 202 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: 112 J/kg
Mixed-layer CIN: -183 J/kg
Mixed-layer LCL: 1274 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: -29 m²/s²
0-3 km storm-relative helicity: -22 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 12, 2:30 AM MDT, 11 hours 22 minutes earlier.

Area forecast discussion, Jun 12, 2:30 AM MDT, 11 hours 22 minutes before

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In the hours before

Special weather statement, Jun 12, 10:15 AM MDT, 3 hours 37 minutes before

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<body>
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    <section class="card" role="status" aria-live="polite">
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Special weather statement, Jun 12, 10:15 AM MDT, 3 hours 37 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>
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The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 12, 4:48 PM MDT	Severe Thunderstorm Warning	CYS	Sioux	47 min
Jun 12, 5:07 PM MDT	Severe Thunderstorm Warning	CYS	Morrill, Scotts Bluff	33 min
Jun 12, 5:39 PM MDT	Severe Thunderstorm Warning	CYS	Morrill	31 min
Jun 12, 2:43 PM MDT	Severe Thunderstorm Warning	CYS	Laramie	47 min
Jun 12, 3:32 PM MDT	Severe Thunderstorm Warning	CYS	Laramie	48 min
Jun 12, 4:33 PM MDT	Tornado Warning	CYS	Converse	32 min
Jun 12, 5:05 PM MDT	Tornado Warning	CYS	Converse	30 min
Jun 12, 5:37 PM MDT	Tornado Warning	CYS	Converse	28 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.