Sussex County
Delaware — Natural Disaster Risk Assessment
MediumComposite Risk Score
National percentile: 94th
Sussex County faces medium composite natural disaster risk (NRI Risk Index score 94.1, 94th national percentile), driven primarily by cold wave and coastal flood exposure. Expected annual loss across all 18 hazard types is $119M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Top Hazards
All 18 Hazard Risks
| Cold Wave | High | 0.79 / yr | $17M |
| Coastal Flood | Very High | 3.65 / yr | $14M |
| Hurricane | High | 0.17 / yr | $35M |
| Winter Weather | Very High | 7.03 / yr | $727K |
| Riverine Flood | Medium | 2.54 / yr | $43M |
| Heat Wave | Medium | 5.03 / yr | $2M |
| Drought | Medium | 4.26 / yr | $1M |
| Strong Wind | High | 2.36 / yr | $1M |
| Wildfire | Low | 0.00 / yr | $538K |
| Lightning | High | 32.75 / yr | $665K |
| Ice Storm | Medium | 0.40 / yr | $385K |
| Earthquake | Low | 0.00 / yr | $2M |
| Tornado | Low | 0.34 / yr | $2M |
| Hail | Low | 0.92 / yr | $306K |
| Landslide | Very Low | 0.13 / yr | $1K |
| Avalanche | 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 Sussex County?
Sussex County has a composite FEMA National Risk Index score of 94.1 out of 100, placing it in the Medium category and the 94th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Sussex County?
The three highest-rated hazards are Cold Wave (High, $17M EAL), Coastal Flood (Very High, $14M EAL), Hurricane (High, $35M EAL). These account for most of the county's expected annual losses.
How does Sussex County compare to other Delaware counties?
Sussex County ranks #2 of 3 Delaware 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. Sussex County's $119M EAL is a statistical average, not a guarantee for any specific year or address.