Mercer County
New Jersey — Natural Disaster Risk Assessment
HighComposite Risk Score
National percentile: 95th
Mercer County faces high composite natural disaster risk (NRI Risk Index score 95.4, 95th national percentile), driven primarily by strong wind and winter weather exposure. Expected annual loss across all 18 hazard types is $176M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Top Hazards
All 18 Hazard Risks
| Strong Wind | Very High | 7.02 / yr | $13M |
| Winter Weather | Very High | 10.64 / yr | $1M |
| Riverine Flood | High | 3.64 / yr | $114M |
| Ice Storm | Very High | 1.09 / yr | $2M |
| Heat Wave | Medium | 10.96 / yr | $7M |
| Hurricane | High | 0.11 / yr | $18M |
| Earthquake | Medium | 0.00 / yr | $11M |
| Lightning | High | 33.63 / yr | $1M |
| Cold Wave | Medium | 0.84 / yr | $5M |
| Tornado | Medium | 0.09 / yr | $4M |
| Wildfire | Low | 0.00 / yr | $216K |
| Drought | Low | 3.22 / yr | $305K |
| Coastal Flood | Low | 6.17 / yr | $329K |
| Landslide | Very Low | 0.07 / yr | $2K |
| Hail | Very Low | 2.40 / yr | $110K |
| 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 Mercer County?
Mercer County has a composite FEMA National Risk Index score of 95.4 out of 100, placing it in the High category and the 95th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Mercer County?
The three highest-rated hazards are Strong Wind (Very High, $13M EAL), Winter Weather (Very High, $1M EAL), Riverine Flood (High, $114M EAL). These account for most of the county's expected annual losses.
How does Mercer County compare to other New Jersey counties?
Mercer County ranks #9 of 21 New Jersey 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. Mercer County's $176M EAL is a statistical average, not a guarantee for any specific year or address.