Hamilton County, Indiana Natural Disaster Risk
FEMA National Risk Index assessment · IN
MediumComposite Risk Score
National percentile: 89th
Hamilton County faces medium composite natural disaster risk (NRI Risk Index score 88.8, 89th national percentile), driven primarily by tornado and hail exposure. Expected annual loss across all 18 hazard types is $129M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Hamilton County carries a medium composite natural disaster risk, with a National Risk Index score of 88.8 out of 100 — placing it in the 89th national percentile and near the national midpoint for natural-disaster risk. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
The county's risk is driven primarily by tornado (violently rotating columns of air capable of catastrophic local damage) at High risk — $30M in expected annual loss and about 0.31 events per year; hail (ice stones from severe thunderstorms that damage property and crops) at Medium risk — $4M in expected annual loss and about 4.38 events per year; and winter weather (heavy snow, blizzards, and hazardous winter conditions) at High risk — $740K in expected annual loss and about 10.26 events per year. Across all hazards, FEMA estimates $129M in expected annual loss for a population of 347K.
Beyond physical exposure, Hamilton 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 federal record bears this out: Hamilton County has received 19 federal disaster declarations since 1965, including 8 for severe storm events and 3 for snowstorm events. The most recent was Severe Winter Storm (winter storm), declared in January 2026.
Among 92 Indiana counties, Hamilton County ranks #5 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Tornado | High | 0.31 / yr | $30M |
| Hail | Medium | 4.38 / yr | $4M |
| Winter Weather | High | 10.26 / yr | $740K |
| Riverine Flood | Medium | 1.82 / yr | $73M |
| Cold Wave | Medium | 3.42 / yr | $9M |
| Heat Wave | Medium | 4.32 / yr | $4M |
| Earthquake | Low | 0.00 / yr | $5M |
| Lightning | High | 45.79 / yr | $1M |
| Strong Wind | Medium | 4.76 / yr | $2M |
| Ice Storm | Medium | 0.99 / yr | $448K |
| Drought | Low | 1.39 / yr | $267K |
| Landslide | Very Low | 0.09 / yr | $2K |
| Hurricane | Very Low | 0.01 / yr | $16K |
| Wildfire | Very Low | 0.00 / yr | $13K |
| 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
Hamilton County has received 19 federal disaster declarations since 1965, most recently Severe Winter Storm in January 2026. Most frequent causes: Severe Storm (8), Snowstorm (3), Biological (2).
| Declared | Type | Disaster |
|---|---|---|
| January 2026 | Winter Storm | Severe Winter Storm |
| April 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| April 2014 | Severe Storm | Severe Winter Storm and Snowstorm |
| June 2008 | Severe Storm | Severe Storms, Flooding, and Tornadoes |
| March 2007 | Snowstorm | Snow |
| September 2005 | Hurricane | Hurricane Katrina Evacuation |
| January 2005 | Severe Storm | Severe Winter Storms and Flooding |
| January 2005 | Snowstorm | Snow |
| June 2004 | Severe Storm | Severe Storms, Tornadoes, and Flooding |
Showing the 10 most recent of 19 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Hamilton County?
Hamilton County has a composite FEMA National Risk Index score of 88.8 out of 100, placing it in the Medium category and the 89th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Hamilton County?
The three highest-rated hazards are Tornado (High, $30M EAL), Hail (Medium, $4M EAL), Winter Weather (High, $740K EAL). These account for most of the county's expected annual losses.
How does Hamilton County compare to other Indiana counties?
Hamilton County ranks #5 of 92 Indiana counties for overall natural disaster risk, with a medium rating.
How many federally declared disasters has Hamilton County had?
FEMA records 19 federal disaster declarations for Hamilton County since 1965, most often 8 for severe storm events and 3 for snowstorm events. The most recent was Severe Winter Storm, declared in January 2026.
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. Hamilton County's $129M EAL is a statistical average, not a guarantee for any specific year or address.