Alert archive / Utah / Winter Weather Advisories in 2021

Winter Weather Advisory 15, NWS Salt Lake City, UT

April 13, 20216 counties in Utah; Uinta County, Wyoming

NWS Salt Lake City, UT issued this winter weather advisory at Apr 13, 2021, 8:52 PM MDT for 6 counties in Utah; Uinta County, Wyoming. It took effect at Apr 14, 2021, 12:00 AM MDT. It was in force for 23 hr.

The area

The counties it named.

The facts

Issued: Apr 13, 2021, 8:52 PM MDT (02:52 UTC)
In effect from: Apr 14, 2021, 12:00 AM MDT
Expired: Apr 14, 2021, 10:44 PM MDT
In force: 23 hr
Issued by: NWS Salt Lake City, UT

Counties Duchesne County, UT, Juab County, UT, Salt Lake County, UT, Summit County, UT, Utah County, UT, Wasatch County, UT, Uinta County, WY

The radar

The Salt Lake City radar (KMTX), 128 km from the middle of the area, began a volume at 02:55 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

Salt Lake City I, UT (KSLC), launched 00:00Z, 2.9 hours before the alert went out and 58 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: 2480 m above ground
0-6 km bulk shear: 64 kt
0-1 km storm-relative helicity: 21 m²/s²
0-3 km storm-relative helicity: 25 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 Salt Lake City, UT wrote its last area forecast discussion before this winter weather advisory went out at Apr 13, 3:44 PM MDT, 5 hours 8 minutes earlier.

Area forecast discussion, Apr 13, 3:44 PM MDT, 5 hours 8 minutes before

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Hazardous weather outlook, Apr 13, 3:48 PM MDT, 5 hours 4 minutes before

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In the hours before

Local storm report, Apr 13, 5:36 PM MDT, 3 hours 16 minutes before

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Local storm report, Apr 13, 7:30 PM MDT, 1 hour 22 minutes before

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  <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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</body>
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The office that day

Everything else NWS Salt Lake City, UT issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 13, 9:01 PM MDT	Wind Advisory	SLC	Garfield, Kane, San Juan, Washington, Wayne	24 hr
Apr 14, 3:51 PM MDT	Special Weather Statement	SLC	Utah	24 min
Apr 14, 3:52 PM MDT	Special Weather Statement	SLC	Utah	23 min
Apr 14, 4:16 PM MDT	Special Weather Statement	SLC	Utah	44 min

Nearby

Winter Weather Advisories in Utah, 2021 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.