Box Elder County, Utah: Natural Disaster Risk and History
Box Elder County, Utah has a Relatively Low natural-hazard risk rating in FEMA's National Risk Index (v1.20, December 2025): a score of 55.9 out of 100, higher than about 55% of US counties, with wildfires, earthquakes and avalanches scoring highest of its 18 hazards and $31 million a year in expected losses.
OpenFEMA lists 7 federal disaster declarations that included Box Elder County since 1977, not counting 2 for COVID-19; the latest is DR-4311-UT (Severe Winter Storms and Flooding, declared 21 April 2017). NOAA's Storm Prediction Center recorded 10 tornadoes touching Box Elder County from 1950 to 2025.
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Population 57,579 Buildings worth $11 billion Area 6,797 sq mi Risk rank in Utah 9 of 29 FIPS 49003
All 18 hazards, highest risk first
FEMA National Risk Index| Hazard | Risk rating | Score | Expected loss a year | How often | Events in record |
|---|---|---|---|---|---|
| Wildfire | Relatively Moderate | 95.4 | $6.5 million | about once every 65 years | — |
| Earthquake | Relatively Moderate | 93.3 | $16 million | about once every 72 years | — |
| Avalanche | Relatively Moderate | 83.0 | $1.1 million | about once every 2.7 years | 11 |
| Winter weather | Relatively Moderate | 72.7 | $251,033 | about 13 a year | 238 |
| Strong wind | Relatively Moderate | 66.5 | $1.5 million | about once every 1.4 years | 30 |
| Lightning | Relatively Moderate | 61.6 | $594,988 | about 31 a year | 98,919 strikes |
| Drought | Relatively Low | 60.6 | $492,803 | about 113 a year | 2,996 |
| Landslide | Very Low | 46.9 | $1,897 | about 3.1 a year | — |
| Heat wave | Relatively Low | 43.8 | $458,423 | about 2.7 a year | 32 |
| Cold wave | Very Low | 21.9 | $434,095 | about once every 12 years | 1.6 |
| Inland flooding | Very Low | 19.5 | $4.0 million | about once every 7.0 years | 4 |
| Ice storm | Very Low | 13.9 | $14,026 | about once every 67 years | 0 |
| Tornado | Very Low | 12.6 | $169,774 | about once every 3.2 years | 5 |
| Volcanic activity | Very Low | 10.1 | — | rarer than once in 1,000 years | 1 |
| Hail | Very Low | 7.8 | $37,754 | about once every 5.4 years | 8.4 |
| Coastal flooding | Not Applicable | — | — | — | — |
| Hurricane | Not Applicable | — | — | — | — |
| Tsunami | Not Applicable | — | — | — | — |
Score: FEMA's percentile among US counties that face the hazard (higher = more risk). Expected loss: FEMA's modelled average yearly loss to buildings, people (as a statistical value) and crops. How often: FEMA's annualised frequency of the hazard in the county; for some hazards it counts event-days, so it is a rough guide, not a forecast. "Not Applicable" means FEMA does not model that hazard here.
Federal disaster declarations 7
Most common: Flood 5, Coastal Storm 1, Drought 1.
| Decade | Declarations | Incident types |
|---|---|---|
| 1970s | 1 | Drought |
| 1980s | 2 | Flood ×2 |
| 2000s | 2 | Coastal Storm, Flood |
| 2010s | 2 | Flood ×2 |
The last 7
Widest declarations that included Box Elder County
- Hurricane Katrina Evacuation (2005, EM-3223-UT): 29 Utah counties designated.
- Drought (1977, EM-3024-UT): 27 Utah counties designated.
- Severe Storms, Landslides & Flooding (1983, DR-680-UT): 22 Utah counties designated.
Named storms in its declarations: Hurricane Katrina (2005).
Not counted above: 2 COVID-19 ("Biological") declarations — in 2020 every US county was included. Utah also had 2 statewide declarations with no county list.
Tornado record since 1950 10
| Tornadoes touching the county | 10 |
|---|---|
| Strongest-rated | (E)F0 ×10 |
| Peak month | August (4) |
| Deadliest | — |
| Longest path | 14 Aug 1968, F0, 4.1 mi path |
| Most recent | 28 May 2018, EF0, 0.1 mi path |
| Deaths / injuries on those paths | 0 / 0 |
| Rating | (E)F0 | (E)F1 | (E)F2 | (E)F3 | (E)F4 | (E)F5 | Unrated |
|---|---|---|---|---|---|---|---|
| Count | 10 | 0 | 0 | 0 | 0 | 0 | 0 |
| Decade | 1950s | 1960s | 1970s | 1980s | 1990s | 2000s | 2010s | 2020s |
|---|---|---|---|---|---|---|---|---|
| Count | 0 | 2 | 1 | 3 | 1 | 2 | 1 | 0 |
Deaths and injuries are for each tornado's whole path, which can run beyond this county. F-scale ratings before February 2007, Enhanced Fujita (EF) after.
How Box Elder County compares with its 5 nearest counties
| County | Distance | Overall risk | Score | Top hazard |
|---|---|---|---|---|
| Box Elder County (this page) | — | Relatively Low | 55.9 | Wildfire |
| Oneida County, ID | 88 km | Very Low | 1.4 | Wildfire |
| Cassia County, ID | 89 km | Relatively Low | 43.6 | Wildfire |
| Weber County | 112 km | Relatively Moderate | 87.0 | Earthquake |
| Davis County | 116 km | Relatively Moderate | 87.8 | Earthquake |
| Cache County | 118 km | Relatively Low | 66.5 | Earthquake |
Nearest by distance between county centres. Every county in Utah, ranked.
Vulnerability and resilience
| Social vulnerability | Very Low 10.6 |
|---|---|
| Community resilience | Very High 93.1 |
| Community risk factor | 0.62 |
| Expected annual loss, all hazards | $31 million |
FEMA scales expected losses up where social vulnerability is high (people who may find it harder to prepare, evacuate or recover) and down where community resilience is high. A factor above 1 raises the risk score. For social vulnerability a high rating is worse; for resilience a high rating is better.
Prepare for Box Elder County's main hazards
- Right now: National Weather Service alerts for Utah · all official warnings on Global Incident Tracker.
- Wildfire: US wildfires now · Wildfire smoke: what protects you
- Earthquake: Earthquakes today · Earthquake safety guide
- Avalanche: Official warnings now
- Your property's flood zone: FEMA Flood Map Service Center ↗ — this page cannot tell you that.
- Official preparedness guidance: Ready.gov ↗ and your county emergency management office.
What this page shows, and what it misses
FEMA's National Risk Index rates a whole county against every other US county; it is a planning-level estimate for nationwide comparison, not a flood-zone map and not a substitute for a local risk assessment or the risk to one home. Declarations are presidential disaster, emergency and fire management declarations that named this county; state declarations and SBA or USDA designations are not included. Tornadoes are counted when the county is one of up to four listed on the track; 670 tornadoes that crossed a state line carry no county list in NOAA's file and are left out.
Federal Emergency Management Agency (FEMA), National Risk Index Dataset: National Risk Index Counties - v1.20.0 (December 2025). Retrieved from https://services.arcgis.com/XG15cJAlne2vxtgt/ArcGIS/rest/services/National_Risk_Index_Counties/FeatureServer/0/query on November 2, 2026, 1:20 PM EST. This product uses the Federal Emergency Management Agency’s National Risk Index dataset API or downloadable datasets but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).
Federal Emergency Management Agency (FEMA), OpenFEMA Dataset: Disaster Declarations Summaries - v2, retrieved from https://www.fema.gov/api/open/v2/DisasterDeclarationsSummaries on November 2, 2026, 1:21 PM EST. This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).
Tornado records: NOAA/NWS Storm Prediction Center, Severe Weather Database, tornadoes 1950–2025 (https://www.spc.noaa.gov/wcm/data/1950-2025_actual_tornadoes.csv, downloaded 2 November 2026). Public domain; not endorsed by NOAA. Compiled by Global Incident Tracker.
Questions about Box Elder County
What natural disasters is Box Elder County, Utah most at risk from?
Box Elder County, Utah has a Relatively Low natural-hazard risk rating in FEMA's National Risk Index (v1.20, December 2025): a score of 55.9 out of 100, higher than about 55% of US counties, with wildfires, earthquakes and avalanches scoring highest of its 18 hazards and $31 million a year in expected losses.
How many federal disaster declarations has Box Elder County had?
OpenFEMA lists 7 federal disaster declarations that included Box Elder County since 1977, not counting 2 for COVID-19; the latest is DR-4311-UT (Severe Winter Storms and Flooding, declared 21 April 2017). Another 2 Utah declarations were made statewide without a county list.
How many tornadoes have hit Box Elder County?
NOAA's Storm Prediction Center recorded 10 tornadoes touching Box Elder County from 1950 to 2025.
Is the National Risk Index a flood zone map?
No. The National Risk Index is a planning-level estimate for a whole county, built for nationwide comparison. It does not tell you the flood zone or the risk of a single property: for that, look up the address on FEMA's Flood Map Service Center (msc.fema.gov) and ask your local floodplain manager.