California tornado risk
Los Angeles County has the highest tornado risk in California, scoring 97.7 out of 100 — rated "Relatively High" by FEMA's National Risk Index. Recorded tornado events across California have decreased 30% over the past five years compared to the prior five-year period.
| # | County | NRI score | Rating |
NOAA events 2016–2026 |
|---|---|---|---|---|
| 1 | Los Angeles County | 97.7 | Relatively High | 6 |
| 2 | Riverside County | 86.7 | Relatively Moderate | 3 |
| 3 | Orange County | 83.7 | Relatively Moderate | 0 |
| 4 | San Bernardino County | 78.8 | Relatively Moderate | 2 |
| 5 | Alameda County | 65.8 | Relatively Moderate | 0 |
| 6 | Sacramento County | 65 | Relatively Moderate | 4 |
| 7 | San Diego County | 64.4 | Relatively Low | 1 |
| 8 | Fresno County | 57.1 | Relatively Low | 5 |
| 9 | Santa Clara County | 55.8 | Relatively Low | 0 |
| 10 | Contra Costa County | 49.9 | Relatively Low | 0 |
| 11 | San Joaquin County | 49 | Relatively Low | 1 |
| 12 | Ventura County | 42.4 | Relatively Low | 2 |
| 13 | San Francisco County | 34.9 | Relatively Low | 0 |
| 14 | Solano County | 34.1 | Relatively Low | 0 |
| 15 | San Mateo County | 30.6 | Relatively Low | 0 |
| 16 | Tulare County | 30.3 | Relatively Low | 1 |
| 17 | Monterey County | 28.7 | Relatively Low | 1 |
| 18 | Butte County | 28.2 | Relatively Low | 2 |
| 19 | Stanislaus County | 27.8 | Relatively Low | 2 |
| 20 | Merced County | 26.2 | Relatively Low | 0 |
| 21 | Placer County | 23.3 | Very Low | 1 |
| 22 | Yolo County | 22.4 | Very Low | 1 |
| 23 | Kern County | 19.8 | Very Low | 2 |
| 24 | Madera County | 19.3 | Very Low | 3 |
| 25 | Santa Cruz County | 18.7 | Very Low | 3 |
| 26 | Marin County | 18.6 | Very Low | 0 |
| 27 | Napa County | 18.3 | Very Low | 1 |
| 28 | Nevada County | 17.9 | Very Low | 0 |
| 29 | Kings County | 16.4 | Very Low | 0 |
| 30 | Shasta County | 15.4 | Very Low | 0 |
| 31 | Sonoma County | 15.4 | Very Low | 0 |
| 32 | Sutter County | 14.9 | Very Low | 1 |
| 33 | Yuba County | 14.9 | Very Low | 1 |
| 34 | El Dorado County | 13.7 | Very Low | 1 |
| 35 | Tehama County | 12.9 | Very Low | 4 |
| 36 | Imperial County | 11.4 | Very Low | 0 |
| 37 | Lake County | 10.9 | Very Low | 0 |
| 38 | Mendocino County | 10.5 | Very Low | 1 |
| 39 | San Benito County | 10.2 | Very Low | 2 |
| 40 | Plumas County | 9.8 | Very Low | 0 |
| 41 | Colusa County | 9.3 | Very Low | 1 |
| 42 | Glenn County | 8.8 | Very Low | 0 |
| 43 | Calaveras County | 8 | Very Low | 1 |
| 44 | Humboldt County | 7.9 | Very Low | 1 |
| 45 | Tuolumne County | 7.9 | Very Low | 1 |
| 46 | Mariposa County | 6.4 | Very Low | 1 |
| 47 | San Luis Obispo County | 6.1 | Very Low | 2 |
| 48 | Amador County | 6 | Very Low | 0 |
| 49 | Santa Barbara County | 5.4 | Very Low | 1 |
| 50 | Trinity County | 4.7 | Very Low | 0 |
| 51 | Del Norte County | 3.3 | Very Low | 0 |
| 52 | Lassen County | 3.2 | Very Low | 3 |
| 53 | Inyo County | 2.9 | Very Low | 1 |
| 54 | Mono County | 2.5 | Very Low | 0 |
| 55 | Sierra County | 2.4 | Very Low | 0 |
| 56 | Siskiyou County | 1.9 | Very Low | 0 |
| 57 | Alpine County | 1.1 | Very Low | 0 |
| 58 | Modoc County | 1.1 | Very Low | 0 |
Source: FEMA National Risk Index v1.20.0, December 2025. Scores are 0–100 percentile rankings among all US counties. See the methodology page for definitions. Download the full CSV for all counties.
Tornado risk nationally:
Other hazard risks in California:
Frequently asked questions
What is the highest tornado risk county in California?
Los Angeles County, CA has the highest tornado risk in California, with a FEMA National Risk Index score of 97.7 out of 100 (rated "Relatively High").
What causes tornado risk in California?
Tornado risk concentrates in the central and southern plains ("Tornado Alley") and the Southeast ("Dixie Alley"), where atmospheric conditions favor supercell thunderstorm development. The highest scores often belong to counties with significant mobile home and manufactured housing stock, which carries disproportionate tornado mortality risk.