Dunn County, Wisconsin
Natural disaster risk, federal disaster history and flood insurance facts.
Dunn County, Wisconsin has a relatively low overall risk from natural hazards in FEMA's National Risk Index. Its risk score is lower than 51% of US counties. It ranks 50th of 72 counties in Wisconsin. The costliest hazards here are inland flooding, cold waves and tornadoes. FEMA estimates about $22 million a year in expected losses, or roughly $489 per resident. Since 1965 it has been included in 11 federal disaster or emergency declarations for natural events (9 major disasters). The most recent was in September 2005 (Hurricane Katrina Evacuation). Fewer than 1 in 100 homes here carry federal flood insurance (50 policies).
FEMA National Risk Index December 2025; OpenFEMA declarations to Nov 6, 2026; NFIP records. Updated November 6, 2026.
Top risks in Dunn County
- Check the FEMA flood map for your address, and ask the seller or landlord about past flooding.
- Price a flood policy now. Most new federal policies take 30 days to start.
- Insulate pipes in outside walls, crawl spaces and garages.
- Know how to shut off the main water valve.
- Pick a shelter spot: a basement, or an inside room on the lowest floor with no windows.
- Turn on emergency alerts on your phone and keep a weather radio.
All 18 hazards
What the ratings mean ›| Hazard | Rating | Score | Expected loss a year | |
|---|---|---|---|---|
| Inland flooding | 50.2 | $10M | ||
| Cold wave | 79.0 | $5M | ||
| Tornado | 68.3 | $3M | ||
| Strong wind | 79.6 | $2M | ||
| Hail | 79.4 | $1M | ||
| Heat wave | 54.8 | $662K | ||
| Lightning | 64.1 | $563K | ||
| Winter weather | 43.3 | $74K | ||
| Ice storm | 35.0 | $59K | ||
| Landslide | 84.1 | $37K | ||
| Earthquake | 4.6 | $7K | ||
| Wildfire | 11.9 | $6K | ||
| Drought | 17.1 | $3K |
Scores are percentiles: a score of 90 means higher risk than about 90% of US counties for that hazard. Hazards FEMA does not rate here are left out. Social vulnerability is very low and community resilience is relatively moderate in FEMA's measures.
Federal disaster history
Recent disasters nationwide ›Declarations by decade
Federal declarations for natural events that included Dunn County. 2020s bar runs to November 2026.
By type
Most recent
Show all 11
Wisconsin also had 8 statewide declarations that did not name single counties.
Storm history since 1951
Tornado risk by county ›The National Weather Service has logged 347 storm reports in Dunn County since 1951, with 23 deaths and 85 injuries and about $66 million in reported damage. The strongest on record here was an F5 tornado on June 4, 1958.
Strongest tornadoes
| Date | Strength | Near | Hurt / killed |
|---|---|---|---|
| Jun 4, 1958 | F5 | – | 54 / 20 |
| Jun 4, 1958 | F5 | – | 0 / 0 |
| Sep 12, 1951 | F3 | – | 1 / 0 |
| Jul 15, 1980 | F2 | – | 12 / 1 |
| Sep 12, 1982 | F2 | – | 0 / 0 |
Most damaging storms
| Date | Type | Near | Damage |
|---|---|---|---|
| Jun 4, 1958 | Tornado | – | $25M |
| Jun 4, 1958 | Tornado | – | $25M |
| Jul 15, 1980 | Tornado | – | $3M |
| Sep 12, 1982 | Tornado | – | $3M |
| May 19, 1996 | Thunderstorm Wind | Connorsville | $2M |
| May 15, 1998 | Tornado | Meridean | $2M |
Source: NOAA Storm Events Database, county-based reports through Jun 19, 2026. Tornado records start in 1950, hail and wind in 1955, and floods and other storm types in 1996, so older decades undercount. Damage is in dollars of the year it happened and is often an estimate. Winter storms, heat and hurricanes are logged by forecast zone, not county, so they are not counted here.
Flood insurance in Dunn County
Check your address flood zone ›National Flood Insurance Program (NFIP) records only; private flood policies are not included. Home counts as of Aug 3, 2026. Since 2021 NFIP prices each home separately under Risk Rating 2.0, so your price depends on the building, not the county. Ask an agent for a quote.
Homes in Dunn County
Older homes and mobile homes usually suffer more damage in storms, floods and earthquakes, and can cost more to insure. If you are buying, ask about roof age, foundation bolting and any retrofits. Source: US Census Bureau, American Community Survey 2020 to 2024 5-year estimates; 18,983 housing units.
Compare in Wisconsin
All 72 ›| Largest counties | Overall risk | Top hazard |
|---|---|---|
| Milwaukee County | Cold wave | |
| Dane County | Inland flooding | |
| Waukesha County | Inland flooding | |
| Brown County | Inland flooding | |
| Racine County | Inland flooding | |
| Outagamie County | Inland flooding | |
| Winnebago County | Inland flooding | |
| Kenosha County | Cold wave |
Neighboring counties
| County | Overall risk | Declarations |
|---|---|---|
| Eau Claire County | 7 | |
| St. Croix County | 9 | |
| Chippewa County | 9 | |
| Barron County | 8 | |
| Polk County | 8 | |
| Pierce County | 11 | |
| Pepin County | 11 |
Common questions about Dunn County
What is the biggest natural hazard in Dunn County?
Inland flooding has the highest expected yearly losses in Dunn County, about $9.6 million a year in FEMA's estimate. Cold wave is second at $4.8 million.
How many federal disasters has Dunn County had?
Dunn County has been included in 11 federal disaster or emergency declarations for natural events since 1965, including 9 major disasters. The most recent was Hurricane Katrina Evacuation in September 2005.
Is Dunn County a high-risk place to live?
Its overall rating is Relatively Low, 50th highest of 72 in Wisconsin. A county rating covers the whole area. Risk at one address can be much higher or lower, so check the FEMA flood map and ask about the home's history.
Do I need flood insurance in Dunn County?
Standard home insurance does not cover flooding. About 1 in 333 homes in Dunn County has federal flood insurance. Lenders require it in mapped high-risk zones, but many flood claims come from outside those zones.
How many tornadoes has Dunn County had?
NOAA records list 24 tornadoes in Dunn County since 1950. The strongest was an F5 tornado on June 4, 1958. The weather service has also logged 132 hail reports and 16 floods here.
Sources: FEMA National Risk Index (December 2025), OpenFEMA Disaster Declarations Summaries, and NFIP policy and claims data. Hazard Compass is independent and not affiliated with FEMA. These figures describe the whole county, not a single property, and are not insurance or safety advice. Report a problem.