Lake County, Illinois Natural Disaster Risk
FEMA National Risk Index assessment · IL
HighComposite Risk Score
National percentile: 96th
Lake County faces high composite natural disaster risk (NRI Risk Index score 96.0, 96th national percentile), driven primarily by cold wave and tornado exposure. Expected annual loss across all 18 hazard types is $266M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Lake County carries a high composite natural disaster risk, with a National Risk Index score of 96.0 out of 100 — placing it in the 96th 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.
The county's risk is driven primarily by cold wave (prolonged spells of dangerously low temperatures) at Very High risk — $43M in expected annual loss and about 4.57 events per year; tornado (violently rotating columns of air capable of catastrophic local damage) at Very High risk — $47M in expected annual loss and about 0.67 events per year; and strong wind (damaging straight-line winds outside of tornadoes and hurricanes) at Very High risk — $8M in expected annual loss and about 5.47 events per year. Across all hazards, FEMA estimates $266M in expected annual loss for a population of 713K.
Beyond physical exposure, Lake County has a very 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: Lake County has received 17 federal disaster declarations since 1965, including 5 for snowstorm events and 4 for flood events. The most recent was Covid-19 Pandemic (biological), declared in March 2020.
Among 102 Illinois counties, Lake County ranks #4 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Cold Wave | Very High | 4.57 / yr | $43M |
| Tornado | Very High | 0.67 / yr | $47M |
| Strong Wind | Very High | 5.47 / yr | $8M |
| Riverine Flood | High | 2.00 / yr | $155M |
| Lightning | High | 36.72 / yr | $2M |
| Heat Wave | Medium | 2.50 / yr | $5M |
| Hail | Medium | 4.06 / yr | $2M |
| Earthquake | Low | 0.00 / yr | $4M |
| Ice Storm | Medium | 0.46 / yr | $196K |
| Winter Weather | Medium | 15.56 / yr | $125K |
| Landslide | Very Low | 0.10 / yr | $1K |
| Wildfire | Very Low | 0.00 / yr | $44K |
| Drought | Low | 7.15 / yr | $91K |
| Coastal Flood | Very Low | 0.01 / yr | $6K |
| Hurricane | Very Low | 0.01 / yr | $7K |
| Avalanche | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
| Volcanic Activity | Very Low | 0.00 / yr | $0 |
Disaster History
Lake County has received 17 federal disaster declarations since 1965, most recently Covid-19 Pandemic in March 2020. Most frequent causes: Snowstorm (5), Flood (4), Severe Storm (3).
| Declared | Type | Disaster |
|---|---|---|
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| 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 |
| March 2008 | Snowstorm | Record Snow and Near Record Snow |
| September 2007 | Severe Storm | Severe Storms and Flooding |
| September 2005 | Hurricane | Hurricane Katrina Evacuation |
| January 2001 | Snowstorm | Illinois Winter Snow Storms |
| January 1999 | Snowstorm | Il-Winter Storm 1/1/99 |
Showing the 10 most recent of 17 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Lake County?
Lake County has a composite FEMA National Risk Index score of 96.0 out of 100, placing it in the High category and the 96th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Lake County?
The three highest-rated hazards are Cold Wave (Very High, $43M EAL), Tornado (Very High, $47M EAL), Strong Wind (Very High, $8M EAL). These account for most of the county's expected annual losses.
How does Lake County compare to other Illinois counties?
Lake County ranks #4 of 102 Illinois counties for overall natural disaster risk, with a high rating.
How many federally declared disasters has Lake County had?
FEMA records 17 federal disaster declarations for Lake County since 1965, most often 5 for snowstorm events and 4 for flood 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. Lake County's $266M EAL is a statistical average, not a guarantee for any specific year or address.