Johnson County, Missouri Natural Disaster Risk
FEMA National Risk Index assessment · MO
LowComposite Risk Score
National percentile: 55th
Johnson County faces low composite natural disaster risk (NRI Risk Index score 54.9, 55th national percentile), driven primarily by cold wave and heat wave exposure. Expected annual loss across all 18 hazard types is $24M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
FEMA's National Risk Index rates Johnson County at low composite risk, with a National Risk Index score of 54.9 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.
Most of Johnson County's expected losses come from cold wave (prolonged spells of dangerously low temperatures) at Medium risk — $5M in expected annual loss and about 2.21 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 13.63 events per year; and ice storm (freezing rain that coats surfaces in heavy, damaging ice) at Medium risk — $418K in expected annual loss and about 0.75 events per year. Across all hazards, FEMA estimates $24M in expected annual loss for a population of 54K.
Beyond physical exposure, Johnson County has a very low social vulnerability rating (how susceptible the population is to harm) and a medium community resilience rating (its capacity to prepare for and recover from disasters). Both measures sit toward the lower end, indicating relatively modest population sensitivity.
The county's disaster history tells the same story: Johnson County has received 21 federal disaster declarations since 1965, including 10 for severe storm events and 4 for flood events. The most recent was Covid-19 Pandemic (biological), declared in March 2020.
Among 115 Missouri counties, Johnson County ranks #52 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Cold Wave | Medium | 2.21 / yr | $5M |
| Heat Wave | Medium | 13.63 / yr | $2M |
| Ice Storm | Medium | 0.75 / yr | $418K |
| Winter Weather | Medium | 10.53 / yr | $191K |
| Hail | Low | 6.68 / yr | $669K |
| Drought | Low | 11.08 / yr | $429K |
| Landslide | Very Low | 0.20 / yr | $4K |
| Riverine Flood | Low | 4.18 / yr | $12M |
| Tornado | Low | 0.45 / yr | $2M |
| Earthquake | Very Low | 0.00 / yr | $358K |
| Lightning | Low | 49.99 / yr | $299K |
| Strong Wind | Low | 4.78 / yr | $549K |
| Wildfire | Very Low | 0.00 / yr | $18K |
| Hurricane | Very Low | 0.01 / yr | $10K |
| 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
Johnson County has received 21 federal disaster declarations since 1965, most recently Covid-19 Pandemic in March 2020. Most frequent causes: Severe Storm (10), Flood (4), Severe Ice Storm (3).
| Declared | Type | Disaster |
|---|---|---|
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| August 2015 | Severe Storm | Severe Storms, Tornadoes, Straight-Line Winds, and Flooding |
| March 2011 | Severe Storm | Severe Winter Storm and Snowstorm |
| February 2011 | Severe Storm | Severe Winter Storm |
| January 2009 | Severe Ice Storm | Severe Winter Storm |
| June 2008 | Severe Storm | Severe Storms and Flooding |
| December 2007 | Severe Ice Storm | Severe Winter Storms |
| March 2006 | Severe Storm | Severe Storms, Tornadoes and Flooding |
| September 2005 | Hurricane | Hurricane Katrina Evacuation |
Showing the 10 most recent of 21 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Johnson County?
Johnson County has a composite FEMA National Risk Index score of 54.9 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 Johnson County?
The three highest-rated hazards are Cold Wave (Medium, $5M EAL), Heat Wave (Medium, $2M EAL), Ice Storm (Medium, $418K EAL). These account for most of the county's expected annual losses.
How does Johnson County compare to other Missouri counties?
Johnson County ranks #52 of 115 Missouri counties for overall natural disaster risk, with a low rating.
How many federally declared disasters has Johnson County had?
FEMA records 21 federal disaster declarations for Johnson County since 1965, most often 10 for severe storm 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. Johnson County's $24M EAL is a statistical average, not a guarantee for any specific year or address.