Winnebago County, Wisconsin severe weather history spans 411 recorded events between 1959 and 2026. The dominant hazard is thunderstorm wind, accounting for 46.2% of all recorded events. It ranks #1,213 nationally and #26 in Wisconsin.
411
Recorded events
3
Direct deaths
63
Direct injuries
$61.0M
Property damage
The record
What the Winnebago County, Wisconsin severe weather history record shows
Across the archive, Winnebago County, Wisconsin severe weather history averages 6.1 recorded events a year. The busiest stretch on record is the 2010s, with 110 events logged in that decade alone. Roughly 76 events fall before 1990 and 335 from 1990 onward — a gap that reflects the expansion of NOAA reporting practice as much as the weather itself.
The deadliest hazard in the Winnebago County, Wisconsin record is thunderstorm wind, responsible for 2 direct deaths. The costliest is hail, with $20.2M in reported property damage. In total, 10 distinct hazard types appear in this county archive, each listed with its own dated record below.
By hazard type
Every hazard type recorded in Winnebago County
| Hazard | Events | Deaths | Damage | Max | Span |
|---|---|---|---|---|---|
| Thunderstorm Wind | 190 | 2 | $10.8M | 87 | 1964–2025 |
| Hail | 141 | 0 | $20.2M | 4.25 | 1964–2025 |
| Tornado | 31 | 1 | $9.8M | F4 | 1959–2020 |
| Funnel Cloud | 12 | 0 | $0 | 0 | 1999–2013 |
| Heavy Rain | 11 | 0 | $0 | 0 | 2010–2015 |
| Lightning | 9 | 0 | $755K | 0 | 1997–2018 |
| Flood | 7 | 0 | $629K | 0 | 1999–2026 |
| Flash Flood | 7 | 0 | $18.8M | 0 | 2003–2026 |
| Seiche | 2 | 0 | $0 | 0 | 1998–1998 |
| Waterspout | 1 | 0 | $0 | 0 | 1996–1996 |
Decade by decade
Winnebago County, Wisconsin severe weather history by decade
Reporting practice changed over time — early decades are undercounted, not calmer.
Tornado tracks
Paths crossing this county
36 mapped tornado paths intersect this county: 31 touched down inside it and 5 crossed in from a neighbouring county. This comes from path geometry, not county-tagged reports.
| Date | Scale | Deaths | Injuries | Path length | Origin |
|---|---|---|---|---|---|
| 1956-04-03 | EF4 | 7 | 50 | 11.5 mi | Crossed in |
| 1984-04-27 | EF4 | 1 | 19 | 27.5 mi | Touched down here |
| 1974-04-21 | EF4 | 0 | 35 | 26.0 mi | Crossed in |
| 1992-09-07 | EF2 | 0 | 1 | 8.5 mi | Crossed in |
| 1964-05-08 | EF2 | 0 | 5 | 30.6 mi | Touched down here |
| 2017-06-14 | EF1 | 0 | 0 | 8.0 mi | Touched down here |
| 2011-04-10 | EF1 | 0 | 0 | 27.7 mi | Crossed in |
| 2011-04-10 | EF1 | 0 | 0 | 14.9 mi | Crossed in |
| 2010-05-04 | EF1 | 0 | 0 | 0.7 mi | Touched down here |
| 2008-07-19 | EF1 | 0 | 0 | 0.5 mi | Touched down here |
Significant events
Deadliest events on record in Winnebago County
| Date | Type | Location | Deaths | Injuries | Damage |
|---|---|---|---|---|---|
| Apr 27, 1984 | Tornado | 1 | 10 | $2.5M | |
| Jun 3, 2020 | Thunderstorm Wind | LAKE BUTTE DES MORTS | 1 | 0 | $0 |
| Jul 16, 1997 | Thunderstorm Wind | OSHKOSH | 1 | 0 | $150K |
| Apr 21, 1974 | Tornado | 0 | 35 | $2.5M | |
| May 9, 1964 | Tornado | 0 | 5 | $2.5M | |
| Aug 20, 2010 | Thunderstorm Wind | NEENAH | 0 | 4 | $0 |
| Jul 18, 2015 | Thunderstorm Wind | (OSH)WITTMAN FLD OSH | 0 | 3 | $0 |
| Jun 12, 2001 | Thunderstorm Wind | OMRO | 0 | 2 | $4.5M |
From the record
What the reports say
Written by National Weather Service staff at the time of the event · public domain
Heavy rainfall, totaling 5.41 inches for the day, over already saturated ground caused widespread flash flooding in the Oshkosh area. Sewage backed up into many basements and the foundations of some homes on the south side of the city crumbled, making them uninhabitable. The flooding destroyed 20 homes, caused major damage to 150, and caused minor damage to over 400 others. Several schools sustained damage, including Lourdes High School and the attached St. John Neumann Middle School, which had extensive water and sewage damage. Water built up in the parking lot and caved in windows on the school's lower level. Flood waters rose over five feet, destroying classrooms, athletic equipment, carpets and computers. Damage to the schools was well over $1 million. The University of Wisconsin-Oshkosh campus also sustained some water damage. High water made 50 to 75 percent of the streets impassible, including parts of U.S. Highways 41 and 45. It also washed out a railroad bridge causing a train to derail and spill diesel fuel into the floodwaters.
Thunderstorm downburst wind gusts, estimated in the 75 to 100 mph range, caused major damage to 2 large industrial buildings in the Neenah-Menasha area. Much of the west-facing wall of one building was blow inward. The high winds also downed trees and power lines, knocked down an 80-foot ham radio tower, bent a large flagpole, downed fences and threw a carport into a yard two houses down the street.
The tornado that formed near Poy Sippi crossed into Winnebago County at 8:04 pm CDT (1904 CST). The tornado moved along the north shore of Lake Poygan, causing most of its damage near Boom Bay on the northeast shore. Two homes were heavily damaged as portions of their roofs were partially ripped off (DI 2, DOD 4). Several other houses sustained lesser damage in this area. In addition, two small mobile homes were rolled on their side (DI 3, DOD 5) and many trees were uprooted or snapped. The tornado dissipated about 2 miles west of Winchester, although damage occurred east and southeast of this location from straight-line thunderstorm winds. The average path width was 100 yards.
Context
Risk, population and federal disasters
Relatively Moderate
FEMA NRI risk rating
171,769
Population (ACS)
$226K
Median home value
12
Federal declarations
| Declared | Incident | Title | Type |
|---|---|---|---|
| Jun 30, 2026 | Flood | SEVERE STORMS, TORNADOES, AND FLOODING | DR |
| Apr 4, 2020 | Biological | COVID-19 PANDEMIC | DR |
| Apr 4, 2020 | Biological | COVID-19 PANDEMIC | DR |
| Mar 13, 2020 | Biological | COVID-19 | EM |
| Jun 14, 2008 | Severe Storm | SEVERE STORMS, TORNADOES, AND FLOODING | DR |
| Sep 13, 2005 | Hurricane | HURRICANE KATRINA EVACUATION | EM |
Quick answers
Frequently asked
How many severe weather events have been recorded in Winnebago County, Wisconsin?
411 events are on record between 1959 and 2026, causing 3 direct deaths and $61.0M in property damage.
What is the most common severe weather hazard in Winnebago County?
Thunderstorm Wind, with 190 recorded events — 46.2% of everything in the archive for this county.
How many tornadoes have crossed Winnebago County?
36 mapped tornado paths intersect the county boundary; 31 of them touched down inside it. This is derived from path geometry, not county-tagged reports.
How many federal disaster declarations cover Winnebago County?
12 federal disaster declarations from FEMA include Winnebago County, each tied to a specific incident period.
How risky is Winnebago County compared with the rest of the country?
FEMA's National Risk Index rates Winnebago County as relatively moderate risk, placing it in the 87 percentile of its state for expected annual loss.
Where does the Winnebago County, Wisconsin severe weather history data come from?
Every figure is drawn from United States federal public-domain records: NOAA/NCEI Storm Events for the event archive, NOAA SPC SVRGIS for mapped tornado paths, FEMA for disaster declarations and risk ratings, and the U.S. Census for population context. Dates are shown in UTC and recent entries may still be revised by NOAA.
Nearby
Neighbouring counties
- Waushara County 268
- Wood County 354
- Waupaca County 360
- Waukesha County 787
- Washington County 418
- Washburn County 261
Cite this page
“Winnebago County, Wisconsin.” Severe Weather History. severeweatherhistory.com/county/wisconsin/winnebago-county/ · Data: NOAA/NCEI, FEMA, U.S. Census — public domain.