Name: Winter Storm in Wisconsin, January 17 to 18, 2020
Start: 2020-01-17T14:00
End: 2020-01-18T16:00
Location: Wisconsin

Where it happened

Every event with a place to put it; 9 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 9

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS MPX wrote it up.

A large storm system, which produced heavy snow during the onset, switched over to freezing drizzle, then back to light snow before transitioning to blowing snow and blizzard conditions. The storm started Friday morning, January 17th with a surge of initial deep moisture advecting northward across the Upper Midwest. A dry layer at mid-levels kept the snowfall across southwest, and south central Minnesota before this layer saturated by noon. There was a 3 to 5 hour period of heavy snowfall that produced snowfall rates of 1 inch per hour. A few areas in southwest Minnesota had already received 4 to 6 inches of snow before noon. This area of snow moved northeast and caused heavy snow bands across east central and central Minnesota, as well as west central Wisconsin by the afternoon. As quickly as the snow started, it ended by the late afternoon, and early evening as a dry slot at mid-levels cutoff any ice crystal producing clouds. This dry slot, and the accompany freezing drizzle once the snow ended, caused a layer of ice to form on the snow that fell earlier.

By sunrise, ice crystal producing clouds spread across the Upper Midwest as the main upper storm moved across the area. Periods of light snow fell across the region, but most of the accumulating snowfall had ended. The cold front moved across Minnesota, and into western Wisconsin by noon. Temperatures fell 10 to 20 degrees behind this front along with strong gusty winds developing. These winds created significant blowing and drifting snow in western Wisconsin, especially in open country. The winds slowly abated during the evening, but blowing snow continued.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Twin Cities, MN wrote its last area forecast discussion before the first event at Jan 17, 11:04 AM CST, 2 hours 56 minutes earlier.

Area forecast discussion, Jan 17, 11:04 AM CST, 2 hours 56 minutes before

<!doctype html>
<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.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

Hazardous weather outlook, Jan 17, 12:07 PM CST, 1 hour 53 minutes before

<!doctype html>
<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.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

9 winter storm. Local standard time, as filed.

Winter Storm, Pepin

When: January 17, 2:00 PM CST to January 18, 4:00 PM CST
Where: Pepin forecast zone
Reported by: Trained Spotter
Coordinates: 44.483, -92.150 (the zone’s center; the record gives no point)

Snowfall rates of 1/2 inch per hour occurred during the late afternoon and evening of Friday, January 17th. Gusty winds accompany the snowfall and continued through the storm. Some freezing drizzle also occurred. Locally 5 to 6 inches of snow fell on Friday, and early Saturday. Areas of blowing and drifting snow occurred on Saturday.

Winter Storm, Pierce

When: January 17, 2:00 PM CST to January 18, 4:00 PM CST
Where: Pierce forecast zone
Reported by: Trained Spotter
Coordinates: 44.720, -92.422 (the zone’s center; the record gives no point)

Snowfall rates of 1/2 inch per hour occurred during the late afternoon and evening of Friday, January 17th. Gusty winds accompany the snowfall and continued through the storm. Some freezing drizzle also occurred. Locally 5 to 6 inches of snow fell on Friday, and early Saturday. Areas of blowing and drifting snow occurred on Saturday.

Winter Storm, St. Croix

When: January 17, 2:00 PM CST to January 18, 4:00 PM CST
Where: St. Croix forecast zone
Reported by: Trained Spotter
Coordinates: 45.034, -92.453 (the zone’s center; the record gives no point)

Snowfall rates of 1/2 inch per hour occurred during the late afternoon and evening of Friday, January 17th. Gusty winds accompany the snowfall and continued through the storm. Some freezing drizzle also occurred. Locally 5 to 6 inches of snow fell on Friday, and early Saturday. Areas of blowing and drifting snow occurred on Saturday.