Alert archive / South Dakota / Dense Fog Advisories in 2021

Dense Fog Advisory 1, NWS Sioux Falls, SD

January 1, 202118 counties in South Dakota; 11 counties in Iowa; 8 counties in Minnesota

NWS Sioux Falls, SD issued this dense fog advisory at Jan 1, 2021, 5:56 PM CST for 18 counties in South Dakota; 11 counties in Iowa; 8 counties in Minnesota. It was in force for 21 hr.

The area

The counties it named.

The facts

Issued: Jan 1, 2021, 5:56 PM CST (23:56 UTC)
Expired: Jan 2, 2021, 3:00 PM CST
In force: 21 hr
Issued by: NWS Sioux Falls, SD

All 37 counties

Buena Vista County, IA, Cherokee County, IA, Clay County, IA, Dickinson County, IA, Ida County, IA, Lyon County, IA, O'Brien County, IA, Osceola County, IA, Plymouth County, IA, Sioux County, IA, Woodbury County, IA, Cottonwood County, MN, Jackson County, MN, Lincoln County, MN, Lyon County, MN, Murray County, MN, Nobles County, MN, Pipestone County, MN, Rock County, MN, Beadle County, SD, Bon Homme County, SD, Brookings County, SD, Clay County, SD, Davison County, SD, Hanson County, SD, Hutchinson County, SD, Kingsbury County, SD, Lake County, SD, Lincoln County, SD, McCook County, SD, Miner County, SD, Minnehaha County, SD, Moody County, SD, Sanborn County, SD, Turner County, SD, Union County, SD, Yankton County, SD

The radar

The Sioux Falls radar (KFSD), 18 km from the middle of the area, began a volume at 23:57 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.

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 1, 2:37 PM CST, 3 hours 19 minutes earlier.

Area forecast discussion, Jan 1, 2:37 PM CST, 3 hours 19 minutes before

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Hazardous weather outlook, Jan 1, 4:26 PM CST, 1 hour 30 minutes before

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</head>
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    <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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Nearby

Dense Fog Advisories in South Dakota, 2021 Dense Fog Advisories in Iowa, 2021 Dense Fog Advisories in Minnesota, 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.