Natrona County, Wyoming Natural Disaster Risk
FEMA National Risk Index assessment · WY
LowComposite Risk Score
National percentile: 69th
Natrona County faces low composite natural disaster risk (NRI Risk Index score 68.9, 69th national percentile), driven primarily by winter weather and wildfire exposure. Expected annual loss across all 18 hazard types is $33M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Natrona County carries a low composite natural disaster risk, with a National Risk Index score of 68.9 out of 100 — placing it in the 69th 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 Natrona County's expected losses come from winter weather (heavy snow, blizzards, and hazardous winter conditions) at Very High risk — $1M in expected annual loss and about 17.39 events per year; wildfire (uncontrolled fires that spread across wildland and into communities) at Medium risk — $3M in expected annual loss and about 0.00 events per year; and landslide (downhill movement of rock, soil, and debris on unstable slopes) at Medium risk — $84K in expected annual loss and about 3.25 events per year. Across all hazards, FEMA estimates $33M in expected annual loss for a population of 80K.
Beyond physical exposure, Natrona County has a 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: Natrona County has received 8 federal disaster declarations since 1978, including 4 for fire events and 2 for flood events. The most recent was Flooding (flood), declared in September 2023.
Among 23 Wyoming counties, Natrona County ranks #3 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Winter Weather | Very High | 17.39 / yr | $1M |
| Wildfire | Medium | 0.00 / yr | $3M |
| Landslide | Medium | 3.25 / yr | $84K |
| Earthquake | Low | 0.00 / yr | $3M |
| Cold Wave | Medium | 1.72 / yr | $5M |
| Avalanche | Medium | 0.10 / yr | $594K |
| Riverine Flood | Medium | 0.82 / yr | $19M |
| Lightning | Medium | 38.23 / yr | $524K |
| Ice Storm | Low | 0.01 / yr | $67K |
| Hail | Low | 0.51 / yr | $217K |
| Tornado | Low | 0.45 / yr | $875K |
| Drought | Very Low | 79.15 / yr | $6K |
| Heat Wave | Very Low | 0.13 / yr | $54K |
| Strong Wind | Very Low | 0.31 / yr | $44K |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Hurricane | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
| Volcanic Activity | Very Low | 0.00 / yr | $0 |
Disaster History
Natrona County has received 8 federal disaster declarations since 1978, most recently Flooding in September 2023. Most frequent causes: Fire (4), Flood (2), Biological (2).
| Declared | Type | Disaster |
|---|---|---|
| September 2023 | Flood | Flooding |
| April 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| October 2015 | Fire | Station Fire |
| September 2012 | Fire | Sheep Herder Hill Fire Complex |
| August 2006 | Fire | Jackson Canyon Fire |
| July 2000 | Fire | Wy - Dead Horse Fire |
| May 1978 | Flood | Severe Storms, Flooding & Mudslides |
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Natrona County?
Natrona County has a composite FEMA National Risk Index score of 68.9 out of 100, placing it in the Low category and the 69th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Natrona County?
The three highest-rated hazards are Winter Weather (Very High, $1M EAL), Wildfire (Medium, $3M EAL), Landslide (Medium, $84K EAL). These account for most of the county's expected annual losses.
How does Natrona County compare to other Wyoming counties?
Natrona County ranks #3 of 23 Wyoming counties for overall natural disaster risk, with a low rating.
How many federally declared disasters has Natrona County had?
FEMA records 8 federal disaster declarations for Natrona County since 1978, most often 4 for fire events and 2 for flood events. The most recent was Flooding, declared in September 2023.
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. Natrona County's $33M EAL is a statistical average, not a guarantee for any specific year or address.