Pima County
Arizona — Natural Disaster Risk Assessment
HighComposite Risk Score
National percentile: 99th
Pima County faces high composite natural disaster risk (NRI Risk Index score 99.1, 99th national percentile), driven primarily by heat wave and wildfire exposure. Expected annual loss across all 18 hazard types is $531M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Top Hazards
All 18 Hazard Risks
| Heat Wave | Very High | 8.09 / yr | $133M |
| Wildfire | High | 0.00 / yr | $38M |
| Riverine Flood | Very High | 12.82 / yr | $347M |
| Lightning | Very High | 42.77 / yr | $3M |
| Hail | Medium | 0.24 / yr | $2M |
| Earthquake | Medium | 0.01 / yr | $6M |
| Strong Wind | Medium | 0.79 / yr | $1M |
| Winter Weather | Medium | 1.80 / yr | $200K |
| Drought | Medium | 57.26 / yr | $459K |
| Landslide | Very Low | 2.14 / yr | $2K |
| Avalanche | Very Low | 0.01 / yr | $358 |
| Tornado | Low | 0.26 / yr | $688K |
| Hurricane | Very Low | 0.02 / yr | $5K |
| Cold Wave | Very Low | 0.00 / yr | $150 |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Ice Storm | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
| Volcanic Activity | Very Low | 0.00 / yr | $0 |
Frequently Asked Questions
What is the overall natural disaster risk for Pima County?
Pima County has a composite FEMA National Risk Index score of 99.1 out of 100, placing it in the High category and the 99th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Pima County?
The three highest-rated hazards are Heat Wave (Very High, $133M EAL), Wildfire (High, $38M EAL), Riverine Flood (Very High, $347M EAL). These account for most of the county's expected annual losses.
How does Pima County compare to other Arizona counties?
Pima County ranks #2 of 15 Arizona counties for overall natural disaster risk, with a high rating.
What does Expected Annual Loss (EAL) mean?
EAL is FEMA's estimate of average annual dollar losses from natural hazards, calculated from historical event data and exposure models. Pima County's $531M EAL is a statistical average, not a guarantee for any specific year or address.