LaSalle County
Illinois — Natural Disaster Risk Assessment
MediumComposite Risk Score
National percentile: 86th
LaSalle County faces medium composite natural disaster risk (NRI Risk Index score 86.1, 86th national percentile), driven primarily by cold wave and riverine flood exposure. Expected annual loss across all 18 hazard types is $61M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Top Hazards
All 18 Hazard Risks
| Cold Wave | High | 5.26 / yr | $15M |
| Riverine Flood | Medium | 2.00 / yr | $33M |
| Drought | Medium | 7.80 / yr | $1M |
| Strong Wind | High | 5.94 / yr | $2M |
| Tornado | Medium | 1.08 / yr | $5M |
| Earthquake | Low | 0.00 / yr | $2M |
| Lightning | Medium | 44.02 / yr | $527K |
| Winter Weather | Medium | 15.05 / yr | $131K |
| Heat Wave | Low | 4.37 / yr | $909K |
| Landslide | Low | 0.21 / yr | $5K |
| Hail | Low | 4.10 / yr | $412K |
| Ice Storm | Medium | 0.70 / yr | $149K |
| Hurricane | Very Low | 0.01 / yr | $15K |
| Wildfire | Very Low | 0.00 / yr | $8K |
| 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 LaSalle County?
LaSalle County has a composite FEMA National Risk Index score of 86.1 out of 100, placing it in the Medium category and the 86th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in LaSalle County?
The three highest-rated hazards are Cold Wave (High, $15M EAL), Riverine Flood (Medium, $33M EAL), Drought (Medium, $1M EAL). These account for most of the county's expected annual losses.
How does LaSalle County compare to other Illinois counties?
LaSalle County ranks #16 of 102 Illinois counties for overall natural disaster risk, with a medium 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. LaSalle County's $61M EAL is a statistical average, not a guarantee for any specific year or address.