Mason County
Illinois — Natural Disaster Risk Assessment
LowComposite Risk Score
National percentile: 43th
Mason County faces low composite natural disaster risk (NRI Risk Index score 43.0, 43th national percentile), driven primarily by drought and strong wind exposure. Expected annual loss across all 18 hazard types is $12M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Top Hazards
All 18 Hazard Risks
| Drought | Medium | 4.42 / yr | $1M |
| Strong Wind | Medium | 5.15 / yr | $985K |
| Cold Wave | Medium | 4.37 / yr | $2M |
| Earthquake | Low | 0.00 / yr | $510K |
| Hail | Low | 3.64 / yr | $392K |
| Heat Wave | Low | 7.11 / yr | $473K |
| Tornado | Low | 0.59 / yr | $1M |
| Riverine Flood | Low | 0.93 / yr | $6M |
| Ice Storm | Low | 1.81 / yr | $63K |
| Landslide | Very Low | 0.10 / yr | $480 |
| Winter Weather | Low | 9.74 / yr | $26K |
| Hurricane | Very Low | 0.01 / yr | $7K |
| Lightning | Very Low | 47.41 / yr | $52K |
| Wildfire | Very Low | 0.00 / yr | $584 |
| Avalanche | Very Low | 0.00 / yr | $0 |
| Coastal Flood | 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 Mason County?
Mason County has a composite FEMA National Risk Index score of 43.0 out of 100, placing it in the Low category and the 43th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Mason County?
The three highest-rated hazards are Drought (Medium, $1M EAL), Strong Wind (Medium, $985K EAL), Cold Wave (Medium, $2M EAL). These account for most of the county's expected annual losses.
How does Mason County compare to other Illinois counties?
Mason County ranks #65 of 102 Illinois counties for overall natural disaster risk, with a 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. Mason County's $12M EAL is a statistical average, not a guarantee for any specific year or address.