Alert archive / Wyoming / Winter Weather Advisories in 2021

Winter Weather Advisory 39, NWS Riverton, WY

December 22, 2021Sweetwater County, Wyoming

NWS Riverton, WY issued this winter weather advisory at Dec 22, 2021, 1:56 PM MST for Sweetwater County, Wyoming. It took effect at Dec 23, 2021, 5:00 PM MST. It was in force for .

The area

The counties it named.

The facts

Issued: Dec 22, 2021, 1:56 PM MST (20:56 UTC)
In effect from: Dec 23, 2021, 5:00 PM MST
Expired: Dec 23, 2021, 1:44 AM MST
In force
Issued by: NWS Riverton, WY

County Sweetwater County, WY

The radar

The Riverton/Lander radar (KRIW), 160 km from the middle of the area, began a volume at 20:57 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 12:00Z, 8.9 hours before the alert went out and 162 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: 2970 m above ground
0-6 km bulk shear: 48 kt
0-1 km storm-relative helicity: 50 m²/s²
0-3 km storm-relative helicity: 226 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 weather advisory 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 weather advisory went out at Dec 22, 10:59 AM MST, 2 hours 57 minutes earlier.

Area forecast discussion, Dec 22, 10:59 AM MST, 2 hours 57 minutes before

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Hazardous weather outlook, Dec 22, 3:24 AM MST, 10 hours 32 minutes before

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  <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 22, 3:17 AM MST	High Wind Watch	RIW	Fremont, Johnson, Natrona, Sublette, Sweetwater	22 hr
Dec 22, 1:56 PM MST	Winter Storm Warning	RIW	Fremont, Hot Springs, Lincoln, Park, Sublette, Sweetwater and 1 more	57 hr

Nearby

Winter Weather Advisories in Wyoming, 2021 Every winter weather advisory in 2021

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.