Mercer County, North Dakota Natural Disaster Risk
FEMA National Risk Index assessment · ND
Very LowComposite Risk Score
National percentile: 14th
Mercer County faces very low composite natural disaster risk (NRI Risk Index score 13.9, 14th national percentile), driven primarily by winter weather and hail exposure. Expected annual loss across all 18 hazard types is $8M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Overall natural disaster risk in Mercer County is very low, with a National Risk Index score of 13.9 out of 100 — placing it in the 14th 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.
Most of Mercer County's expected losses come from winter weather (heavy snow, blizzards, and hazardous winter conditions) at Medium risk — $353K in expected annual loss and about 18.42 events per year; hail (ice stones from severe thunderstorms that damage property and crops) at Medium risk — $952K in expected annual loss and about 2.51 events per year; and cold wave (prolonged spells of dangerously low temperatures) at Medium risk — $2M in expected annual loss and about 15.21 events per year. Across all hazards, FEMA estimates $8M in expected annual loss for a population of 8K.
Beyond physical exposure, Mercer 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: Mercer County has received 24 federal disaster declarations since 1966, including 13 for flood events and 4 for severe storm events. The most recent was Flooding (flood), declared in July 2023.
Among 53 North Dakota counties, Mercer County ranks #25 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Winter Weather | Medium | 18.42 / yr | $353K |
| Hail | Medium | 2.51 / yr | $952K |
| Cold Wave | Medium | 15.21 / yr | $2M |
| Ice Storm | Medium | 0.64 / yr | $228K |
| Wildfire | Very Low | 0.00 / yr | $128K |
| Tornado | Low | 0.32 / yr | $624K |
| Strong Wind | Low | 1.52 / yr | $269K |
| Drought | Very Low | 23.28 / yr | $7K |
| Landslide | Very Low | 0.30 / yr | $159 |
| Riverine Flood | Very Low | 0.43 / yr | $3M |
| Heat Wave | Very Low | 1.58 / yr | $43K |
| Lightning | Very Low | 29.70 / yr | $50K |
| Earthquake | Very Low | 0.00 / yr | $6K |
| Avalanche | Very Low | 0.00 / yr | $0 |
| 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
Mercer County has received 24 federal disaster declarations since 1966, most recently Flooding in July 2023. Most frequent causes: Flood (13), Severe Storm (4), Snowstorm (3).
| Declared | Type | Disaster |
|---|---|---|
| July 2023 | Flood | Flooding |
| February 2023 | Snowstorm | Severe Winter Storm, Snowstorm, and Straight-Line Winds |
| April 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| May 2011 | Flood | Flooding |
| April 2011 | Flood | Flooding |
| April 2010 | Flood | Flooding |
| April 2010 | Severe Storm | Severe Winter Storm |
| March 2010 | Flood | Flooding |
| February 2010 | Severe Storm | Severe Winter Storm |
Showing the 10 most recent of 24 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Mercer County?
Mercer County has a composite FEMA National Risk Index score of 13.9 out of 100, placing it in the Very Low category and the 14th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Mercer County?
The three highest-rated hazards are Winter Weather (Medium, $353K EAL), Hail (Medium, $952K EAL), Cold Wave (Medium, $2M EAL). These account for most of the county's expected annual losses.
How does Mercer County compare to other North Dakota counties?
Mercer County ranks #25 of 53 North Dakota counties for overall natural disaster risk, with a very low rating.
How many federally declared disasters has Mercer County had?
FEMA records 24 federal disaster declarations for Mercer County since 1966, most often 13 for flood events and 4 for severe storm events. The most recent was Flooding, declared in July 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. Mercer County's $8M EAL is a statistical average, not a guarantee for any specific year or address.