Franklin County, Ohio Natural Disaster Risk
FEMA National Risk Index assessment · OH
HighComposite Risk Score
National percentile: 98th
Franklin County faces high composite natural disaster risk (NRI Risk Index score 98.1, 98th national percentile), driven primarily by cold wave and heat wave exposure. Expected annual loss across all 18 hazard types is $331M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
FEMA's National Risk Index rates Franklin County at high composite risk, with a National Risk Index score of 98.1 out of 100 — placing it in the 98th national percentile and in the upper tier of natural-disaster risk nationally. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
Most of Franklin County's expected losses come from cold wave (prolonged spells of dangerously low temperatures) at Very High risk — $43M in expected annual loss and about 3.63 events per year; heat wave (prolonged periods of extreme heat that threaten health and infrastructure) at High risk — $25M in expected annual loss and about 4.16 events per year; and riverine flood (rivers and streams overflowing their banks after heavy rain or snowmelt) at High risk — $210M in expected annual loss and about 3.50 events per year. Across all hazards, FEMA estimates $331M in expected annual loss for a population of 1.32M.
Beyond physical exposure, Franklin County has a low social vulnerability rating (how susceptible the population is to harm) and a 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: Franklin County has received 20 federal disaster declarations since 1974, including 11 for severe storm events and 3 for snowstorm events. The most recent was Covid-19 Pandemic (biological), declared in March 2020.
Among 88 Ohio counties, Franklin County ranks #1 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Cold Wave | Very High | 3.63 / yr | $43M |
| Heat Wave | High | 4.16 / yr | $25M |
| Riverine Flood | High | 3.50 / yr | $210M |
| Hail | High | 3.11 / yr | $8M |
| Tornado | High | 0.29 / yr | $29M |
| Winter Weather | High | 11.32 / yr | $869K |
| Strong Wind | High | 1.81 / yr | $3M |
| Lightning | High | 46.45 / yr | $2M |
| Earthquake | Medium | 0.00 / yr | $10M |
| Ice Storm | High | 0.73 / yr | $743K |
| Landslide | Low | 0.12 / yr | $4K |
| Drought | Low | 1.59 / yr | $244K |
| Hurricane | Very Low | 0.01 / yr | $73K |
| 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
Franklin County has received 20 federal disaster declarations since 1974, most recently Covid-19 Pandemic in March 2020. Most frequent causes: Severe Storm (11), Snowstorm (3), Biological (2).
| Declared | Type | Disaster |
|---|---|---|
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| August 2012 | Severe Storm | Severe Storms and Straight-Line Winds |
| 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 20 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Franklin County?
Franklin County has a composite FEMA National Risk Index score of 98.1 out of 100, placing it in the High category and the 98th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Franklin County?
The three highest-rated hazards are Cold Wave (Very High, $43M EAL), Heat Wave (High, $25M EAL), Riverine Flood (High, $210M EAL). These account for most of the county's expected annual losses.
How does Franklin County compare to other Ohio counties?
Franklin County ranks #1 of 88 Ohio counties for overall natural disaster risk, with a high rating.
How many federally declared disasters has Franklin County had?
FEMA records 20 federal disaster declarations for Franklin County since 1974, most often 11 for severe storm events and 3 for snowstorm events. The most recent was Covid-19 Pandemic, declared in March 2020.
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. Franklin County's $331M EAL is a statistical average, not a guarantee for any specific year or address.