Ontonagon County, Michigan
Natural disaster risk, federal disaster history and flood insurance facts.
Ontonagon County, Michigan has a very low overall risk from natural hazards in FEMA's National Risk Index. Its risk score is lower than 96% of US counties. It ranks 81st of 83 counties in Michigan. The costliest hazards here are inland flooding, cold waves and strong wind. FEMA estimates about $2.4 million a year in expected losses, or roughly $411 per resident. Since 1977 it has been included in 6 federal disaster or emergency declarations for natural events (3 major disasters). The most recent was in June 2013 (flooding). Only 12 homes here carry federal flood insurance.
FEMA National Risk Index December 2025; OpenFEMA declarations to Nov 6, 2026; NFIP records. Updated November 6, 2026.
Top risks in Ontonagon 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.
- Secure outdoor furniture and trash bins before storms.
- Have trees near the house checked.
All 18 hazards
What the ratings mean ›| Hazard | Rating | Score | Expected loss a year | |
|---|---|---|---|---|
| Inland flooding | 13.0 | $1M | ||
| Cold wave | 46.2 | $676K | ||
| Strong wind | 16.7 | $118K | ||
| Lightning | 26.6 | $79K | ||
| Winter weather | 57.8 | $70K | ||
| Hail | 15.9 | $45K | ||
| Tornado | 7.5 | $32K | ||
| Wildfire | 31.6 | $13K | ||
| Heat wave | 5.9 | $6K | ||
| Drought | 22.4 | $6K | ||
| Ice storm | 2.2 | $717 | ||
| Landslide | 8.5 | $16 | ||
| Coastal flooding | 15.0 | $0 |
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 relatively high and community resilience is relatively high in FEMA's measures.
Federal disaster history
Recent disasters nationwide ›Declarations by decade
Federal declarations for natural events that included Ontonagon County. 2020s bar runs to November 2026.
By type
Most recent
Michigan also had 6 statewide declarations that did not name single counties.
Storm history since 1953
Tornado risk by county ›The National Weather Service has logged 152 storm reports in Ontonagon County since 1953 and about $10.8 million in reported damage. The strongest on record here was an F1 tornado on June 30, 1953.
Strongest tornadoes
| Date | Strength | Near | Hurt / killed |
|---|---|---|---|
| Jun 30, 1953 | F1 | – | 0 / 0 |
| Aug 19, 2011 | EF0 | Ontonagon | 0 / 0 |
| May 12, 1988 | F0 | – | 0 / 0 |
Most damaging storms
| Date | Type | Near | Damage |
|---|---|---|---|
| Apr 13, 2023 | Flood | Ewen | $8M |
| Jul 23, 2025 | Flash Flood | Firesteel | $2M |
| Apr 28, 2013 | Flood | Merriweather | $550K |
| Jun 30, 1953 | Tornado | – | $250K |
| Jul 21, 2016 | Thunderstorm Wind | Ontonagon | $100K |
| Jun 29, 2026 | Thunderstorm Wind | Ontonagon | $75K |
Source: NOAA Storm Events Database, county-based reports through Jul 27, 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 Ontonagon 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 Ontonagon 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; 5,238 housing units.
Compare in Michigan
All 83 ›| Largest counties | Overall risk | Top hazard |
|---|---|---|
| Wayne County | Inland flooding | |
| Oakland County | Inland flooding | |
| Macomb County | Inland flooding | |
| Kent County | Inland flooding | |
| Genesee County | Inland flooding | |
| Washtenaw County | Inland flooding | |
| Ottawa County | Inland flooding | |
| Ingham County | Inland flooding |
Neighboring counties
| County | Overall risk | Declarations |
|---|---|---|
| Houghton County | 7 | |
| Ashland County, WI | 12 | |
| Gogebic County | 7 | |
| Iron County | 5 | |
| Cook County, MN | 8 | |
| Keweenaw County | 3 |
Common questions about Ontonagon County
What is the biggest natural hazard in Ontonagon County?
Inland flooding has the highest expected yearly losses in Ontonagon County, about $1.3 million a year in FEMA's estimate. Cold wave is second at $675,635.
How many federal disasters has Ontonagon County had?
Ontonagon County has been included in 6 federal disaster or emergency declarations for natural events since 1977, including 3 major disasters. The most recent was Flooding in June 2013.
Is Ontonagon County a high-risk place to live?
Its overall rating is Very Low, 81st highest of 83 in Michigan. 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 Ontonagon County?
Standard home insurance does not cover flooding. About 1 in 500 homes in Ontonagon 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 Ontonagon County had?
NOAA records list 3 tornadoes in Ontonagon County since 1950. The strongest was an F1 tornado on June 30, 1953. The weather service has also logged 57 hail reports and 7 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.