Tornado and Damaging Wind in Wisconsin, October 7, 2017

Name: Tornado and Damaging Wind in Wisconsin, October 7, 2017
Start: 2017-10-07T15:59
End: 2017-10-07T16:22
Location: Wisconsin

October 7, 2017 · NWS MKX · 2 events in 2 counties and zones

A strong upper trough and cold front resulted in a broken line of convection. An EF0 tornado occurred from Madison to Sun Prairie, and straight-line wind damage occurred in Pardeeville.

Where it happened

Every event with a place to put it. 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: $275,000
Crop damage: None recorded
Events: 2

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 MKX wrote it up.

A strong upper trough and cold front resulted in a broken line of convection. An EF0 tornado occurred from Madison to Sun Prairie, and straight-line wind damage occurred in Pardeeville.

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 Milwaukee, WI wrote its last area forecast discussion before the first event at Oct 6, 5:06 PM CST, 22 hours 53 minutes earlier.

Area forecast discussion, Oct 6, 5:06 PM CST, 22 hours 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 Milwaukee radar (KMKX), 67 km away, was scanning. The volume nearest the first event began at 21:58 UTC.

Open the radar archive at this moment

Event by event

1 tornado, 1 thunderstorm wind. Local standard time, as filed.

Tornado, Dane

When: October 7, 3:59 PM CST to 4:15 PM CST
Where: Dane County, 0.73 mi SSW of Maple Bluff to 0.83 mi WNW of Sun Prairie
Rating: EF0
Path length: 9.7 mi
Path width: 100 yd
Property damage: $250,000
Reported by: NWS Storm Survey
Coordinates: 43.090, -89.356

An EF0 tornado started near the intersection of S. First St. and Winnebago St. in Madison and tracked over 9 miles to Sun Prairie, paralleling Highway 151 for most of the path. In Madison, approximately, 200 trees were damaged or destroyed. Some of the trees landed on homes, garages, and vehicles. At least three households were displaced due to damage to their homes. The rear wall of a car wash collapsed, and the three-season porch of a home collapsed. A roof was partially torn away from a commercial building. Many power lines were downed with some arcing. In total, four commercial buildings and 12-18 homes sustained some damage. In Sun Prairie, near and east of the intersection of W. Main St. and O'Keeffe Ave., several traffic standards, streets signs, and construction barrels were damaged or knocked down. A truck topper was removed from a truck and a small wood shed was damaged. Several trees and branches were down, including a tree on a house.

Thunderstorm Wind, Columbia

When: October 7, 4:20 PM CST to 4:22 PM CST
Where: Columbia County, 1.34 mi NW of Pardeeville to 1.44 mi NW of Pardeeville
Measured: 61 kt (70 mph) estimated gust
Property damage: $25,000
Reported by: Storm Chaser
Coordinates: 43.542, -89.301

Several large trees uprooted or snapped. Large branches also down. Structural damage to several homes from trees landing on them. Two pontoon boats that were resting on boat lifts were overturned into the lake.

What these are

Tornado: A violently rotating column of air in contact with the ground and extending from a thunderstorm, filed with its path, width and Fujita or Enhanced Fujita rating from the damage survey.
Thunderstorm Wind: Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Wisconsin in 2017 Every state in 2017 This day in weather history The tornado archive for Wisconsin, 2017 Warnings in Wisconsin, October 2017

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-10-01. Each event’s entry at NCEI: 719368, 719361.