Delaware County, Ohio Natural Disaster Risk
FEMA National Risk Index assessment · OH
LowComposite Risk Score
National percentile: 79th
Delaware County faces low composite natural disaster risk (NRI Risk Index score 78.8, 79th national percentile), driven primarily by hail and winter weather exposure. Expected annual loss across all 18 hazard types is $69M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Overall natural disaster risk in Delaware County is low, with a National Risk Index score of 78.8 out of 100 — placing it in the 79th national percentile and below the national average for natural-disaster risk. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
Risk here concentrates in hail (ice stones from severe thunderstorms that damage property and crops) at Medium risk — $3M in expected annual loss and about 3.28 events per year; winter weather (heavy snow, blizzards, and hazardous winter conditions) at High risk — $603K in expected annual loss and about 11.68 events per year; and ice storm (freezing rain that coats surfaces in heavy, damaging ice) at High risk — $1M in expected annual loss and about 0.60 events per year. Across all hazards, FEMA estimates $69M in expected annual loss for a population of 213K.
Beyond physical exposure, Delaware County has a very low social vulnerability rating (how susceptible the population is to harm) and a very high community resilience rating (its capacity to prepare for and recover from disasters). A less vulnerable population paired with strong resilience helps the community absorb and recover from events.
The county's disaster history tells the same story: Delaware County has received 15 federal disaster declarations since 1965, including 6 for severe storm events and 3 for tornado events. The most recent was Tornadoes (tornado), declared in May 2024.
Among 88 Ohio counties, Delaware County ranks #13 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Hail | Medium | 3.28 / yr | $3M |
| Winter Weather | High | 11.68 / yr | $603K |
| Ice Storm | High | 0.60 / yr | $1M |
| Riverine Flood | Medium | 1.71 / yr | $49M |
| Tornado | Medium | 0.24 / yr | $7M |
| Lightning | Medium | 43.66 / yr | $1M |
| Strong Wind | Medium | 1.92 / yr | $2M |
| Heat Wave | Low | 3.58 / yr | $2M |
| Earthquake | Low | 0.00 / yr | $1M |
| Landslide | Very Low | 0.09 / yr | $2K |
| Cold Wave | Low | 4.53 / yr | $1M |
| Hurricane | Very Low | 0.01 / yr | $20K |
| Wildfire | Very Low | 0.00 / yr | $21K |
| Drought | Very Low | 0.11 / yr | $732 |
| 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 |
Disaster History
Delaware County has received 15 federal disaster declarations since 1965, most recently Tornadoes in May 2024. Most frequent causes: Severe Storm (6), Tornado (3), Snowstorm (3).
| Declared | Type | Disaster |
|---|---|---|
| May 2024 | Tornado | Tornadoes |
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| June 2012 | Severe Storm | Severe Storms |
| October 2008 | Severe Storm | Severe Wind Storm Associated with Tropical Depression Ike |
| April 2008 | Snowstorm | Record Snow and Near Record Snow |
| September 2005 | Hurricane | Hurricane Katrina Evacuation |
| February 2005 | Severe Storm | Severe Winter Storms, Flooding, and Mudslides |
| January 2005 | Snowstorm | Snow |
| September 2004 | Severe Storm | Severe Storms and Flooding |
Showing the 10 most recent of 15 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Delaware County?
Delaware County has a composite FEMA National Risk Index score of 78.8 out of 100, placing it in the Low category and the 79th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Delaware County?
The three highest-rated hazards are Hail (Medium, $3M EAL), Winter Weather (High, $603K EAL), Ice Storm (High, $1M EAL). These account for most of the county's expected annual losses.
How does Delaware County compare to other Ohio counties?
Delaware County ranks #13 of 88 Ohio counties for overall natural disaster risk, with a low rating.
How many federally declared disasters has Delaware County had?
FEMA records 15 federal disaster declarations for Delaware County since 1965, most often 6 for severe storm events and 3 for tornado events. The most recent was Tornadoes, declared in May 2024.
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. Delaware County's $69M EAL is a statistical average, not a guarantee for any specific year or address.