Alert archive / Wyoming / Winter Storm Warnings in 2015

Winter Storm Warning 10, NWS Riverton, WY

December 20, 20154 counties in Wyoming

NWS Riverton, WY issued this winter storm warning at Dec 20, 2015, 10:14 PM MST for 4 counties in Wyoming. It took effect at Dec 21, 2015, 9:00 AM MST. It was in force for 28 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Dec 20, 2015, 10:14 PM MST (05:14 UTC)
In effect from: Dec 21, 2015, 9:00 AM MST
Expired: Dec 22, 2015, 1:08 PM MST
In force: 28 hr
Issued by: NWS Riverton, WY

Counties Fremont County, WY, Lincoln County, WY, Sublette County, WY, Teton County, WY

The radar

The Riverton/Lander radar (KRIW), 120 km from the middle of the area, began a volume at 05:12 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

Riverton, WY (KRIW), launched 00:00Z, 5.2 hours before the alert went out and 126 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: 1149 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: 63 m²/s²
0-3 km storm-relative helicity: 229 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

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

NWS Riverton, WY wrote its last area forecast discussion before this winter storm warning went out at Dec 20, 2:21 PM MST, 7 hours 53 minutes earlier.

Area forecast discussion, Dec 20, 2:21 PM MST, 7 hours 53 minutes before

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Hazardous weather outlook, Dec 20, 3:21 AM MST, 18 hours 53 minutes before

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In the hours before

Special weather statement, Dec 20, 5:38 PM MST, 4 hours 36 minutes before

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<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.
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The office that day

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

Issued	Product	Office	Counties	Lasted
Dec 20, 10:04 PM MST	High Wind Warning	RIW	Fremont, Natrona, Park, Sweetwater	37 hr
Dec 20, 10:14 PM MST	Winter Weather Advisory	RIW	Fremont, Hot Springs, Lincoln, Park, Sublette, Sweetwater and 1 more	71 hr

Nearby

Winter Storm Warnings in Wyoming, 2015 Every winter storm warning in 2015

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.