Aurora County
South Dakota — Natural Disaster Risk Assessment
Very LowComposite Risk Score
National percentile: 20th
Aurora County faces very low composite natural disaster risk (NRI Risk Index score 19.6, 20th national percentile), driven primarily by ice storm and drought exposure. Expected annual loss across all 18 hazard types is $8M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Top Hazards
All 18 Hazard Risks
| Ice Storm | Medium | 0.46 / yr | $539K |
| Drought | Medium | 18.29 / yr | $902K |
| Cold Wave | Medium | 7.00 / yr | $3M |
| Wildfire | Low | 0.00 / yr | $139K |
| Winter Weather | Low | 16.11 / yr | $85K |
| Hail | Low | 4.67 / yr | $302K |
| Tornado | Low | 0.36 / yr | $663K |
| Earthquake | Very Low | 0.00 / yr | $25K |
| Strong Wind | Very Low | 2.90 / yr | $156K |
| Landslide | Very Low | 0.07 / yr | $64 |
| Riverine Flood | Very Low | 0.61 / yr | $2M |
| Heat Wave | Very Low | 6.05 / yr | $16K |
| Lightning | Very Low | 36.26 / yr | $9K |
| Avalanche | Very Low | 0.00 / yr | $0 |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Hurricane | 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 Aurora County?
Aurora County has a composite FEMA National Risk Index score of 19.6 out of 100, placing it in the Very Low category and the 20th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Aurora County?
The three highest-rated hazards are Ice Storm (Medium, $539K EAL), Drought (Medium, $902K EAL), Cold Wave (Medium, $3M EAL). These account for most of the county's expected annual losses.
How does Aurora County compare to other South Dakota counties?
Aurora County ranks #33 of 66 South Dakota counties for overall natural disaster risk, with a very low 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. Aurora County's $8M EAL is a statistical average, not a guarantee for any specific year or address.