Stephenson County, Illinois Natural Disaster Risk
FEMA National Risk Index assessment · IL
LowComposite Risk Score
National percentile: 74th
Stephenson County faces low composite natural disaster risk (NRI Risk Index score 73.9, 74th national percentile), driven primarily by hail and strong wind exposure. Expected annual loss across all 18 hazard types is $29M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Overall natural disaster risk in Stephenson County is low, with a National Risk Index score of 73.9 out of 100 — placing it in the 74th 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 hail (ice stones from severe thunderstorms that damage property and crops) at Medium risk — $2M in expected annual loss and about 3.60 events per year; strong wind (damaging straight-line winds outside of tornadoes and hurricanes) at High risk — $1M in expected annual loss and about 5.09 events per year; and tornado (violently rotating columns of air capable of catastrophic local damage) at Medium risk — $4M in expected annual loss and about 0.48 events per year. Across all hazards, FEMA estimates $29M in expected annual loss for a population of 45K.
Beyond physical exposure, Stephenson County has a medium 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.
History supports the rating: Stephenson County has received 14 federal disaster declarations since 1969, including 4 for flood events and 4 for snowstorm events. The most recent was Covid-19 Pandemic (biological), declared in March 2020.
Among 102 Illinois counties, Stephenson County ranks #30 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Hail | Medium | 3.60 / yr | $2M |
| Strong Wind | High | 5.09 / yr | $1M |
| Tornado | Medium | 0.48 / yr | $4M |
| Drought | Medium | 10.60 / yr | $878K |
| Cold Wave | Medium | 6.32 / yr | $3M |
| Riverine Flood | Medium | 1.25 / yr | $16M |
| Ice Storm | Medium | 0.88 / yr | $191K |
| Heat Wave | Low | 4.74 / yr | $610K |
| Earthquake | Very Low | 0.00 / yr | $360K |
| Landslide | Very Low | 0.11 / yr | $1K |
| Lightning | Low | 39.74 / yr | $187K |
| Winter Weather | Low | 15.89 / yr | $47K |
| Wildfire | Very Low | 0.00 / yr | $11K |
| Hurricane | Very Low | 0.01 / yr | $3K |
| 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
Stephenson County has received 14 federal disaster declarations since 1969, most recently Covid-19 Pandemic in March 2020. Most frequent causes: Flood (4), Snowstorm (4), Severe Storm (3).
| Declared | Type | Disaster |
|---|---|---|
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| September 2019 | Flood | Severe Storms and Flooding |
| March 2011 | Snowstorm | Severe Winter Storm and Snowstorm |
| August 2010 | Severe Storm | Severe Storms and Flooding |
| March 2008 | Snowstorm | Record Snow and Near Record Snow |
| August 2007 | Severe Storm | Severe Storms and Flooding |
| December 2006 | Snowstorm | Snow |
| September 2005 | Hurricane | Hurricane Katrina Evacuation |
| July 1996 | Severe Storm | Severe Storms and Flooding |
Showing the 10 most recent of 14 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Stephenson County?
Stephenson County has a composite FEMA National Risk Index score of 73.9 out of 100, placing it in the Low category and the 74th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Stephenson County?
The three highest-rated hazards are Hail (Medium, $2M EAL), Strong Wind (High, $1M EAL), Tornado (Medium, $4M EAL). These account for most of the county's expected annual losses.
How does Stephenson County compare to other Illinois counties?
Stephenson County ranks #30 of 102 Illinois counties for overall natural disaster risk, with a low rating.
How many federally declared disasters has Stephenson County had?
FEMA records 14 federal disaster declarations for Stephenson County since 1969, most often 4 for flood events and 4 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. Stephenson County's $29M EAL is a statistical average, not a guarantee for any specific year or address.