Natural disaster risk in Delaware, by county
All 3 counties in Delaware, ranked by FEMA's National Risk Index composite risk score, with each one's highest-rated hazard. Other states
At a glance
Highest overall risk: New Castle County (relatively high, score 95.3). Lowest: Kent County (relatively moderate, score 84.5).
Top hazards in Delaware
| Hazard | Counties rated relatively high or very high | Average score |
|---|---|---|
| Winter weather | 3 of 3 | 95.7 |
| Cold wave | 3 of 3 | 94.7 |
| Coastal flooding | 2 of 3 | 83.0 |
| Strong wind | 2 of 3 | 77.7 |
| Hurricane | 1 of 3 | 92.0 |
All counties, highest risk first
| # | County | Overall risk | Highest-rated hazard |
|---|---|---|---|
| 1 | New Castle County | Relatively high 95.3 | Winter weather (very high) |
| 2 | Sussex County | Relatively moderate 94.1 | Coastal flooding (very high) |
| 3 | Kent County | Relatively moderate 84.5 | Cold wave (relatively high) |
How to read these ratings
- Ratings run in five steps: very low, relatively low, relatively moderate, relatively high and very high. They compare a county with every other US county; they are not a measure of danger on their own.
- Scores run from 0 to 100 and are national percentiles. The bar shows the score: a score of 80 means a higher value than 80% of US counties.
- Overall risk combines the expected annual loss with social vulnerability and community resilience.
- Expected annual loss is the average yearly loss to buildings, people and agriculture the model expects from all 18 hazards.
- Social vulnerability describes how hard it may be for people to prepare for and recover from a disaster. Higher is worse.
- Community resilience describes a community's ability to prepare, adapt and recover. Higher is better.
- "Not applicable" means FEMA does not model that hazard there (for example, hurricanes far inland).
About this data
Source: FEMA National Risk Index, version 1.20, released December 2025, published by the Federal Emergency Management Agency (US public domain). About the National Risk Index. The index is a model of relative risk built from historical hazard records, what is exposed and community factors. It is not a forecast, it does not describe any single property, and it is not insurance or financial advice. For decisions about a specific address, check FEMA's flood maps and your local emergency management office.
Questions
Which county in Delaware has the highest natural disaster risk?
New Castle County has the highest composite risk score in Delaware in FEMA's National Risk Index: 95.3, rated relatively high.
Which county in Delaware has the lowest natural disaster risk?
Kent County has the lowest composite risk score in Delaware: 84.5, rated relatively moderate. A low score means lower modelled risk compared with other US counties, not no risk.
What natural disasters is Delaware most at risk from?
Across Delaware, the hazards rated highest in the most counties are winter weather, cold wave, coastal flooding, according to FEMA's National Risk Index. Each county page lists all 18 hazards.
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