Jersey County, Illinois Natural Disaster Risk
FEMA National Risk Index assessment · IL
Very LowComposite Risk Score
National percentile: 19th
Jersey County faces very low composite natural disaster risk (NRI Risk Index score 18.9, 19th national percentile), driven primarily by landslide and heat wave exposure. Expected annual loss across all 18 hazard types is $11M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
FEMA's National Risk Index rates Jersey County at very low composite risk, with a National Risk Index score of 18.9 out of 100 — placing it in the 19th national percentile and among the lowest-risk counties in the country. 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 landslide (downhill movement of rock, soil, and debris on unstable slopes) at Low risk — $32K in expected annual loss and about 0.34 events per year; heat wave (prolonged periods of extreme heat that threaten health and infrastructure) at Medium risk — $2M in expected annual loss and about 11.10 events per year; and earthquake (ground shaking from sudden movement along geologic faults) at Low risk — $909K in expected annual loss and about 0.00 events per year. Across all hazards, FEMA estimates $11M in expected annual loss for a population of 22K.
Beyond physical exposure, Jersey 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.
History supports the rating: Jersey County has received 20 federal disaster declarations since 1969, including 9 for flood events and 5 for severe storm events. The most recent was Severe Storms, Straight-Line Winds, and Tornadoes (tornado), declared in December 2021.
Among 102 Illinois counties, Jersey County ranks #90 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Landslide | Low | 0.34 / yr | $32K |
| Heat Wave | Medium | 11.10 / yr | $2M |
| Earthquake | Low | 0.00 / yr | $909K |
| Cold Wave | Low | 2.21 / yr | $2M |
| Drought | Low | 1.91 / yr | $160K |
| Lightning | Low | 48.88 / yr | $257K |
| Strong Wind | Low | 6.12 / yr | $650K |
| Tornado | Low | 0.33 / yr | $1M |
| Hail | Low | 5.17 / yr | $231K |
| Winter Weather | Very Low | 9.05 / yr | $29K |
| Ice Storm | Very Low | 1.15 / yr | $26K |
| Riverine Flood | Very Low | 1.11 / yr | $3M |
| Hurricane | Very Low | 0.01 / yr | $2K |
| Wildfire | Very Low | 0.00 / yr | $322 |
| 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
Jersey County has received 20 federal disaster declarations since 1969, most recently Severe Storms, Straight-Line Winds, and Tornadoes in December 2021. Most frequent causes: Flood (9), Severe Storm (5), Tornado (2).
| Declared | Type | Disaster |
|---|---|---|
| December 2021 | Tornado | Severe Storms, Straight-Line Winds, and Tornadoes |
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| September 2019 | Flood | Severe Storms and Flooding |
| June 2008 | Severe Storm | Severe Storms and Flooding |
| February 2007 | Severe Ice Storm | Severe Winter Storm |
| September 2005 | Hurricane | Hurricane Katrina Evacuation |
| May 2002 | Tornado | Severe Storms, Tornadoes and Flooding |
| May 1995 | Severe Storm | Severe Storms and Flooding |
| April 1994 | 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 Jersey County?
Jersey County has a composite FEMA National Risk Index score of 18.9 out of 100, placing it in the Very Low category and the 19th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Jersey County?
The three highest-rated hazards are Landslide (Low, $32K EAL), Heat Wave (Medium, $2M EAL), Earthquake (Low, $909K EAL). These account for most of the county's expected annual losses.
How does Jersey County compare to other Illinois counties?
Jersey County ranks #90 of 102 Illinois counties for overall natural disaster risk, with a very low rating.
How many federally declared disasters has Jersey County had?
FEMA records 20 federal disaster declarations for Jersey County since 1969, most often 9 for flood events and 5 for severe storm events. The most recent was Severe Storms, Straight-Line Winds, and Tornadoes, declared in December 2021.
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. Jersey County's $11M EAL is a statistical average, not a guarantee for any specific year or address.