Washington County, Illinois Natural Disaster Risk
FEMA National Risk Index assessment · IL
LowComposite Risk Score
National percentile: 55th
Washington County faces low composite natural disaster risk (NRI Risk Index score 55.2, 55th national percentile), driven primarily by earthquake and heat wave exposure. Expected annual loss across all 18 hazard types is $18M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Overall natural disaster risk in Washington County is low, with a National Risk Index score of 55.2 out of 100 — placing it in the 55th 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 earthquake (ground shaking from sudden movement along geologic faults) at Medium risk — $6M in expected annual loss and about 0.01 events per year; heat wave (prolonged periods of extreme heat that threaten health and infrastructure) at Medium risk — $3M in expected annual loss and about 11.16 events per year; and strong wind (damaging straight-line winds outside of tornadoes and hurricanes) at Medium risk — $1M in expected annual loss and about 5.55 events per year. Across all hazards, FEMA estimates $18M in expected annual loss for a population of 14K.
Beyond physical exposure, Washington County has a medium 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: Washington County has received 9 federal disaster declarations since 2002, including 2 for severe storm events and 2 for biological events. The most recent was Severe Storms, Tornadoes, Straight-Line Winds, and Floodng (flood), declared in September 2024.
Among 102 Illinois counties, Washington County ranks #51 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Earthquake | Medium | 0.01 / yr | $6M |
| Heat Wave | Medium | 11.16 / yr | $3M |
| Strong Wind | Medium | 5.55 / yr | $1M |
| Lightning | Medium | 51.73 / yr | $539K |
| Drought | Medium | 1.66 / yr | $421K |
| Landslide | Very Low | 0.33 / yr | $3K |
| Hail | Low | 4.54 / yr | $365K |
| Cold Wave | Low | 1.37 / yr | $1M |
| Tornado | Low | 0.47 / yr | $1M |
| Winter Weather | Low | 8.26 / yr | $46K |
| Riverine Flood | Low | 0.57 / yr | $5M |
| Hurricane | Very Low | 0.02 / yr | $28K |
| Ice Storm | Very Low | 0.62 / yr | $18K |
| Wildfire | Very Low | 0.00 / yr | $1K |
| 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
Washington County has received 9 federal disaster declarations since 2002, most recently Severe Storms, Tornadoes, Straight-Line Winds, and Floodng in September 2024. Most frequent causes: Severe Storm (2), Biological (2), Tornado (2).
| Declared | Type | Disaster |
|---|---|---|
| September 2024 | Flood | Severe Storms, Tornadoes, Straight-Line Winds, and Floodng |
| August 2023 | Severe Storm | Severe Storms and Flooding |
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| November 2013 | Tornado | Severe Storms, Straight-Line Winds, and Tornadoes |
| June 2011 | Severe Storm | Severe Storms and Flooding |
| March 2011 | Snowstorm | Severe Winter Storm and Snowstorm |
| September 2005 | Hurricane | Hurricane Katrina Evacuation |
| May 2002 | Tornado | Severe Storms, Tornadoes and Flooding |
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Washington County?
Washington County has a composite FEMA National Risk Index score of 55.2 out of 100, placing it in the Low category and the 55th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Washington County?
The three highest-rated hazards are Earthquake (Medium, $6M EAL), Heat Wave (Medium, $3M EAL), Strong Wind (Medium, $1M EAL). These account for most of the county's expected annual losses.
How does Washington County compare to other Illinois counties?
Washington County ranks #51 of 102 Illinois counties for overall natural disaster risk, with a low rating.
How many federally declared disasters has Washington County had?
FEMA records 9 federal disaster declarations for Washington County since 2002, most often 2 for severe storm events and 2 for biological events. The most recent was Severe Storms, Tornadoes, Straight-Line Winds, and Floodng, declared in September 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. Washington County's $18M EAL is a statistical average, not a guarantee for any specific year or address.