Ontario, CA
Local storm history & FEMA National Risk Index data
Ontario is rated Very High for overall natural hazard risk — among the most at-risk counties in the country — based on FEMA's National Risk Index for San Bernardino County, CA. The county's highest-rated hazards are wildfire, landslide, and inland flooding.
Storm events near Ontario
NOAA-recorded tornado, hail, and flood events within 25 miles of Ontario's center, 2016–2026 — the only hazards NOAA reports with exact coordinates, so these counts are specific to Ontario itself, not the whole county.
County-wide hazard risk
Every other hazard FEMA and NOAA track — including drought — is only scored at the county level. These are San Bernardino County's FEMA National Risk Index scores, covering Ontario along with the rest of the county, not a Ontario-specific figure.
| Hazard | NRI score | Rating |
|---|---|---|
| Wildfire | 99.9 | Very High |
| Inland Flooding | 99.8 | Very High |
| Coastal Flooding | — | Not Applicable |
| Earthquake | 99.8 | Very High |
| Heat Wave | 98.4 | Relatively High |
| Tornado | 78.8 | Relatively Moderate |
| Avalanche | 78.5 | Relatively Low |
| Cold Wave | 28.3 | Relatively Low |
| Drought | 33.5 | Relatively Low |
| Hail | 90.9 | Relatively Moderate |
| Hurricane | 0 | No Rating |
| Ice Storm | — | Not Applicable |
| Landslide | 99.9 | Very High |
| Lightning | 95.2 | Relatively High |
| Strong Wind | 97 | Relatively High |
| Tsunami | — | Not Applicable |
| Volcanic Activity | 31.6 | Very Low |
| Winter Weather | 48.4 | Relatively Low |
Source: FEMA National Risk Index v1.20.0, December 2025. See the methodology page for definitions, or the full San Bernardino County risk profile for disaster declarations, social vulnerability, and climate projection data.
Other cities in San Bernardino County:
More on San Bernardino County:
Frequently asked questions
What natural hazards is Ontario, CA at risk of?
Ontario is rated Very High for overall natural hazard risk by FEMA's National Risk Index — among the most at-risk counties in the country. The highest-rated hazards for San Bernardino County, where Ontario is located, are wildfire, landslide, and inland flooding.
What is Ontario's biggest natural hazard risk?
Wildfire is the highest-rated hazard for San Bernardino County, where Ontario is located, scoring 99.9 out of 100 on FEMA's National Risk Index (rated "Very High").
Is Ontario a high-risk area for natural disasters?
Yes — Ontario carries among the most at-risk counties in the country for overall natural hazard risk, per FEMA's National Risk Index rating of "Very High" for San Bernardino County.
Has Ontario had tornadoes, hail, or flooding?
NOAA has recorded 1 tornado, 5 hail, 147 inland flooding events within 25 miles of Ontario since 2016.