Alert archive / South Dakota / Dense Fog Advisories in 2021

Dense Fog Advisory 3, NWS Sioux Falls, SD

January 6, 2021Brule County, Charles Mix County, Gregory County, South Dakota

NWS Sioux Falls, SD issued this dense fog advisory at Jan 6, 2021, 8:37 PM CST for Brule County, Charles Mix County, Gregory County, South Dakota. It took effect at Jan 6, 2021, 9:00 PM CST. It was in force for 11 hr.

The area

The counties it named.

The facts

Issued: Jan 6, 2021, 8:37 PM CST (02:37 UTC)
In effect from: Jan 6, 2021, 9:00 PM CST
Expired: Jan 7, 2021, 8:15 AM CST
In force: 11 hr
Issued by: NWS Sioux Falls, SD

Counties Brule County, SD, Charles Mix County, SD, Gregory County, SD

The radar

The Sioux Falls radar (KFSD), 181 km from the middle of the area, began a volume at 02:40 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.

What forecasters said that day

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

NWS Sioux Falls, SD wrote its last area forecast discussion before this dense fog advisory went out at Jan 6, 4:58 PM CST, 3 hours 39 minutes earlier.

Area forecast discussion, Jan 6, 4:58 PM CST, 3 hours 39 minutes before

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Hazardous weather outlook, Jan 6, 5:11 PM CST, 3 hours 26 minutes before

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  <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.
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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 Sioux Falls, SD issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jan 7, 2:42 PM CST	Dense Fog Advisory	FSD	Bon Homme, Brookings, Clay, Hanson, Hutchinson, Kingsbury and 9 more	20 hr

Nearby

Dense Fog Advisories in South Dakota, 2021 Every dense fog 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; radar from the NEXRAD Level II archive.