Tornado risk by county
Violent rotating columns of air that come down from thunderstorms. Spring is the busiest season, but tornadoes can happen in any month.
Highest expected losses
| # | County | Rating | A year |
|---|---|---|---|
| 1 | Collin County, TX | $420M | |
| 2 | Harris County, TX | $407M | |
| 3 | Cook County, IL | $345M | |
| 4 | Denton County, TX | $145M | |
| 5 | Tarrant County, TX | $144M | |
| 6 | Bexar County, TX | $124M | |
| 7 | Dallas County, TX | $115M | |
| 8 | Oakland County, MI | $102M | |
| 9 | Travis County, TX | $96M | |
| 10 | Hennepin County, MN | $83M | |
| 11 | Jefferson County, KY | $80M | |
| 12 | Hillsborough County, FL | $77M | |
| 13 | Shelby County, TN | $70M | |
| 14 | DuPage County, IL | $67M | |
| 15 | Douglas County, NE | $64M |
Big counties lead this list partly because they have more people and buildings at risk.
Highest per resident
| # | County (100,000+ people) | Per person a year |
|---|---|---|
| 1 | Collin County, TX | $395 |
| 2 | Johnson County, IA | $237 |
| 3 | Morgan County, AL | $193 |
| 4 | Faulkner County, AR | $187 |
| 5 | Minnehaha County, SD | $183 |
| 6 | Etowah County, AL | $167 |
| 7 | Gregg County, TX | $161 |
| 8 | Denton County, TX | $160 |
| 9 | Calhoun County, AL | $160 |
| 10 | Craighead County, AR | $158 |
Expected yearly loss divided by population. A fairer way to compare places of different size.
Lowest risk among large counties
| # | County (250,000+ people) | Rating | Per person a year |
|---|---|---|---|
| 1 | Anchorage Municipality, AK | under $1 | |
| 2 | Clark County, NV | under $1 | |
| 3 | Santa Barbara County, CA | under $1 | |
| 4 | San Luis Obispo County, CA | under $1 | |
| 5 | Kern County, CA | under $1 | |
| 6 | Washoe County, NV | under $1 | |
| 7 | Sonoma County, CA | under $1 | |
| 8 | El Paso County, TX | under $1 | |
| 9 | Lane County, OR | under $1 | |
| 10 | Pima County, AZ | under $1 |
How ratings are spread
The lists above show only the top counties, so they are all rated high. Across all 3,144 rated counties, most are Low or Very Low:
How to prepare
- 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.
- Mobile homes are not safe in a tornado; plan where you would go.
States where it is most often the top hazard
Common questions
Which US county has the highest tornado risk?
Collin County, TX has the highest expected yearly tornado losses in FEMA's National Risk Index, about $420 million a year. Harris County, TX is second at $407 million.
How many counties face tornado risk?
FEMA rates tornado in 3,144 of 3,144 counties in the 50 states and DC. 37 are rated Very High and 272 Relatively High.
Is tornado covered by home insurance?
Usually yes for damage to the home, but check deductibles. Some states and insurers use separate wind, hail or hurricane deductibles.
Other hazards
Source: FEMA National Risk Index (December 2025). Expected annual loss is FEMA's long-run estimate of yearly damage to buildings, people and farm output, in dollars.