Alert archive / Colorado / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 37, NWS Denver/Boulder, CO

July 1, 1987Phillips County, Sedgwick County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Jul 1, 1987, 7:13 PM MDT for Phillips County, Sedgwick County, Colorado. It was in force for 42 min.

The area

The counties it named.

The facts

Issued: Jul 1, 1987, 7:13 PM MDT (01:13 UTC)
Expired: Jul 1, 1987, 7:55 PM MDT
In force: 42 min
Issued by: NWS Denver/Boulder, CO
Area: Whole counties

Counties Phillips County, CO, Sedgwick County, CO

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

N. Platte/Lee Bi, NE (KLBF), launched 00:00Z, 1.2 hours before the alert went out and 154 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: 1802 J/kg
Mixed-layer CIN: -15 J/kg
Mixed-layer LCL: 1678 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 36 m²/s²
0-3 km storm-relative helicity: 112 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 3.0

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.

In the hours before

Special weather statement, Jul 1, 5:02 PM MDT, 2 hours 11 minutes before

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Special weather statement, Jul 1, 5:14 PM MDT, 1 hour 59 minutes before

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Special weather statement, Jul 1, 6:39 PM MDT, 34 minutes before

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<head>
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<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.
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      <p id="message2">
        Please try again in a few minutes.
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        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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The office that day

Everything else NWS Denver/Boulder, CO issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 1, 9:09 PM MDT	Severe Thunderstorm Warning	BOU	Larimer	51 min
Jul 2, 3:02 PM MDT	Severe Thunderstorm Warning	BOU	Arapahoe, Douglas	53 min
Jul 2, 3:34 PM MDT	Tornado Warning	BOU	Adams	26 min
Jul 2, 4:02 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe, Weld	63 min
Jul 2, 4:46 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Morgan, Washington	59 min
Jul 2, 5:45 PM MDT	Severe Thunderstorm Warning	BOU	Douglas	60 min

Nearby

Severe Thunderstorm Warnings in Colorado, 1987 Every severe thunderstorm warning in 1987

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.