Williams County, Ohio
Natural disaster risk, federal disaster history and flood insurance facts.
Williams County, Ohio has a relatively low overall risk from natural hazards in FEMA's National Risk Index. Its risk score is lower than 56% of US counties. It ranks 58th of 88 counties in Ohio. The costliest hazards here are inland flooding, tornadoes and strong wind. FEMA estimates about $12 million a year in expected losses, or roughly $337 per resident. Since 1978 it has been included in 6 federal disaster or emergency declarations for natural events (3 major disasters). The most recent was in June 2012 (severe storms). Only 40 homes here carry federal flood insurance. Since 1978, federal flood insurance has paid about $764,000 on 32 claims here.
FEMA National Risk Index December 2025; OpenFEMA declarations to Nov 6, 2026; NFIP records. Updated November 6, 2026.
Top risks in Williams 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.
- 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.
- 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 | 51.8 | $6M | ||
| Tornado | 74.4 | $3M | ||
| Strong wind | 80.2 | $1M | ||
| Cold wave | 47.4 | $761K | ||
| Hail | 73.6 | $585K | ||
| Earthquake | 63.0 | $480K | ||
| Lightning | 44.4 | $171K | ||
| Heat wave | 33.8 | $148K | ||
| Ice storm | 62.8 | $135K | ||
| Drought | 45.2 | $90K | ||
| Winter weather | 38.1 | $38K | ||
| Hurricane | 31.9 | $15K | ||
| Wildfire | 12.1 | $4K | ||
| Landslide | 41.7 | $652 |
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 moderate 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 Williams County. 2020s bar runs to November 2026.
By type
Most recent
Ohio also had 3 statewide declarations that did not name single counties.
Storm history since 1957
Tornado risk by county ›The National Weather Service has logged 196 storm reports in Williams County since 1957, with 1 death and 25 injuries and about $31.9 million in reported damage. The strongest on record here was an F3 tornado on March 27, 1991.
Strongest tornadoes
| Date | Strength | Near | Hurt / killed |
|---|---|---|---|
| Mar 27, 1991 | F3 | – | 18 / 0 |
| May 6, 1961 | F3 | – | 0 / 0 |
| Aug 25, 1965 | F2 | – | 1 / 0 |
| Jul 4, 1957 | F2 | – | 0 / 0 |
| Aug 22, 1964 | F2 | – | 0 / 0 |
Most damaging storms
| Date | Type | Near | Damage |
|---|---|---|---|
| Mar 27, 1991 | Tornado | – | $25M |
| May 17, 1996 | Flash Flood | Williams County | $3M |
| Aug 25, 1965 | Tornado | – | $3M |
| Jul 4, 1957 | Tornado | – | $250K |
| Jun 23, 2010 | Thunderstorm Wind | Edgerton | $200K |
| Jun 19, 2002 | Lightning | Stryker | $150K |
Source: NOAA Storm Events Database, county-based reports through Apr 22, 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 Williams 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 Williams 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; 16,564 housing units.
Compare in Ohio
All 88 ›| Largest counties | Overall risk | Top hazard |
|---|---|---|
| Franklin County | Inland flooding | |
| Cuyahoga County | Inland flooding | |
| Hamilton County | Inland flooding | |
| Summit County | Inland flooding | |
| Montgomery County | Inland flooding | |
| Lucas County | Inland flooding | |
| Butler County | Inland flooding | |
| Stark County | Inland flooding |
Neighboring counties
| County | Overall risk | Declarations |
|---|---|---|
| Hillsdale County, MI | 6 | |
| DeKalb County, IN | 13 | |
| Fulton County | 7 | |
| Defiance County | 6 | |
| Steuben County, IN | 10 | |
| Henry County | 8 |
Common questions about Williams County
What is the biggest natural hazard in Williams County?
Inland flooding has the highest expected yearly losses in Williams County, about $6.2 million a year in FEMA's estimate. Tornado is second at $2.7 million.
How many federal disasters has Williams County had?
Williams County has been included in 6 federal disaster or emergency declarations for natural events since 1978, including 3 major disasters. The most recent was Severe Storms in June 2012.
Is Williams County a high-risk place to live?
Its overall rating is Relatively Low, 58th highest of 88 in Ohio. 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 Williams County?
Standard home insurance does not cover flooding. About 1 in 500 homes in Williams 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 Williams County had?
NOAA records list 9 tornadoes in Williams County since 1950. The strongest was an F3 tornado on March 27, 1991. The weather service has also logged 43 hail reports and 5 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.