Rock Island County, Illinois Natural Disaster Risk
FEMA National Risk Index assessment · IL
MediumComposite Risk Score
National percentile: 84th
Rock Island County faces medium composite natural disaster risk (NRI Risk Index score 84.1, 84th national percentile), driven primarily by cold wave and strong wind exposure. Expected annual loss across all 18 hazard types is $45M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
FEMA's National Risk Index rates Rock Island County at medium composite risk, with a National Risk Index score of 84.1 out of 100 — placing it in the 84th 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.
Risk here concentrates in cold wave (prolonged spells of dangerously low temperatures) at High risk — $11M in expected annual loss and about 6.26 events per year; strong wind (damaging straight-line winds outside of tornadoes and hurricanes) at High risk — $2M in expected annual loss and about 6.18 events per year; and heat wave (prolonged periods of extreme heat that threaten health and infrastructure) at Medium risk — $4M in expected annual loss and about 7.21 events per year. Across all hazards, FEMA estimates $45M in expected annual loss for a population of 145K.
Beyond physical exposure, Rock Island County has a high 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). Higher vulnerability is partly offset by strong community resilience and recovery capacity.
The county's disaster history tells the same story: Rock Island County has received 15 federal disaster declarations since 1965, including 9 for flood events and 2 for biological events. The most recent was Covid-19 Pandemic (biological), declared in March 2020.
Among 102 Illinois counties, Rock Island County ranks #19 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Cold Wave | High | 6.26 / yr | $11M |
| Strong Wind | High | 6.18 / yr | $2M |
| Heat Wave | Medium | 7.21 / yr | $4M |
| Hail | Medium | 3.99 / yr | $2M |
| Tornado | High | 0.42 / yr | $7M |
| Winter Weather | High | 15.58 / yr | $360K |
| Lightning | High | 44.04 / yr | $1M |
| Landslide | Low | 0.25 / yr | $23K |
| Ice Storm | Medium | 0.67 / yr | $366K |
| Riverine Flood | Medium | 3.07 / yr | $17M |
| Drought | Medium | 8.53 / yr | $464K |
| Earthquake | Low | 0.00 / yr | $451K |
| Hurricane | Very Low | 0.01 / yr | $3K |
| Wildfire | Very Low | 0.00 / yr | $2K |
| 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
Rock Island County has received 15 federal disaster declarations since 1965, most recently Covid-19 Pandemic in March 2020. Most frequent causes: Flood (9), Biological (2), Snowstorm (1).
| Declared | Type | Disaster |
|---|---|---|
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| September 2019 | Flood | Severe Storms and Flooding |
| May 2013 | Flood | Severe Storms, Straight-Line Winds, and Flooding |
| March 2011 | Snowstorm | Severe Winter Storm and Snowstorm |
| June 2008 | Severe Storm | Severe Storms and Flooding |
| September 2005 | Hurricane | Hurricane Katrina Evacuation |
| May 2001 | Flood | Flooding |
| July 1993 | Flood | Severe Storms & Flooding |
| March 1985 | Flood | Severe Storms & 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 Rock Island County?
Rock Island County has a composite FEMA National Risk Index score of 84.1 out of 100, placing it in the Medium category and the 84th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Rock Island County?
The three highest-rated hazards are Cold Wave (High, $11M EAL), Strong Wind (High, $2M EAL), Heat Wave (Medium, $4M EAL). These account for most of the county's expected annual losses.
How does Rock Island County compare to other Illinois counties?
Rock Island County ranks #19 of 102 Illinois counties for overall natural disaster risk, with a medium rating.
How many federally declared disasters has Rock Island County had?
FEMA records 15 federal disaster declarations for Rock Island County since 1965, most often 9 for flood events and 2 for biological 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. Rock Island County's $45M EAL is a statistical average, not a guarantee for any specific year or address.