Sweetwater County, Wyoming: Natural Disaster Risk and History
Sweetwater County, Wyoming has a Very Low natural-hazard risk rating in FEMA's National Risk Index (v1.20, December 2025): a score of 30.6 out of 100, higher than about 30% of US counties, with landslides, winter storms and wildfires scoring highest of its 18 hazards and $12 million a year in expected losses.
OpenFEMA lists 2 federal disaster declarations that included Sweetwater County since 1977, not counting 2 for COVID-19; the latest is DR-4007-WY (Severe Storms, Flooding, and Landslides, declared 22 July 2011). NOAA's Storm Prediction Center recorded 26 tornadoes touching Sweetwater County from 1950 to 2025.
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Population 42,238 Buildings worth $11 billion Area 10,597 sq mi Risk rank in Wyoming 13 of 23 FIPS 56037
All 18 hazards, highest risk first
FEMA National Risk Index| Hazard | Risk rating | Score | Expected loss a year | How often | Events in record |
|---|---|---|---|---|---|
| Landslide | Relatively Moderate | 90.6 | $70,598 | about 2.6 a year | — |
| Winter weather | Relatively High | 85.6 | $338,584 | about 13 a year | 247 |
| Wildfire | Relatively Low | 66.2 | $151,180 | rarer than once in 1,000 years | — |
| Earthquake | Relatively Low | 65.6 | $728,062 | about once every 272 years | — |
| Cold wave | Relatively Low | 58.2 | $1.5 million | about 1.2 a year | 23 |
| Lightning | Relatively Low | 55.9 | $337,168 | about 39 a year | 178,691 strikes |
| Inland flooding | Relatively Low | 52.4 | $8.2 million | about once every 2.5 years | 11 |
| Drought | Very Low | 19.6 | $4,338 | about 12 a year | 3,444 |
| Ice storm | Very Low | 16.1 | $12,537 | about once every 67 years | 0 |
| Hail | Very Low | 14.4 | $55,775 | about once every 15 years | 2.5 |
| Avalanche | Very Low | 12.6 | $14 | about once every 100 years | 0 |
| Strong wind | Very Low | 10.2 | $86,528 | about once every 5.3 years | 8 |
| Tornado | Very Low | 9.4 | $66,200 | about once every 2.8 years | 17 |
| Heat wave | No Rating | 0.0 | — | — | 0 |
| Coastal flooding | Not Applicable | — | — | — | — |
| Hurricane | Not Applicable | — | — | — | — |
| Tsunami | Not Applicable | — | — | — | — |
| Volcanic activity | 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 2
Most common: Severe Storm 1, Drought 1.
| Decade | Declarations | Incident types |
|---|---|---|
| 1970s | 1 | Drought |
| 2010s | 1 | Severe Storm |
The last 2
Widest declarations that included Sweetwater County
- Severe Storms, Flooding, and Landslides (2011, DR-4007-WY): 15 Wyoming counties designated.
- Drought (1977, EM-3043-WY): 4 Wyoming counties designated.
Not counted above: 2 COVID-19 ("Biological") declarations — in 2020 every US county was included. Wyoming also had 1 statewide declaration with no county list.
Tornado record since 1950 26
| Tornadoes touching the county | 26 |
|---|---|
| Strongest-rated | (E)F1 ×5 |
| Peak month | May (7) |
| Deadliest | — |
| Longest path | 26 May 2017, EF0, 11.4 mi path |
| Most recent | 1 Jul 2025, EF0, 0.8 mi path |
| Deaths / injuries on those paths | 0 / 0 |
| Rating | (E)F0 | (E)F1 | (E)F2 | (E)F3 | (E)F4 | (E)F5 | Unrated |
|---|---|---|---|---|---|---|---|
| Count | 20 | 5 | 0 | 0 | 0 | 0 | 1 |
| Decade | 1950s | 1960s | 1970s | 1980s | 1990s | 2000s | 2010s | 2020s |
|---|---|---|---|---|---|---|---|---|
| Count | 0 | 1 | 6 | 3 | 6 | 3 | 5 | 2 |
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 Sweetwater County compares with its 5 nearest counties
| County | Distance | Overall risk | Score | Top hazard |
|---|---|---|---|---|
| Sweetwater County (this page) | — | Very Low | 30.6 | Landslide |
| Daggett County, UT | 101 km | Very Low | 3.7 | Avalanche |
| Moffat County, CO | 129 km | Very Low | 12.1 | Landslide |
| Uinta County | 145 km | Very Low | 16.7 | Winter weather |
| Sublette County | 150 km | Very Low | 21.6 | Landslide |
| Fremont County | 155 km | Relatively Low | 59.7 | Landslide |
Nearest by distance between county centres. Every county in Wyoming, ranked.
Vulnerability and resilience
| Social vulnerability | Very Low 19.3 |
|---|---|
| Community resilience | Very Low 16.4 |
| Community risk factor | 0.89 |
| Expected annual loss, all hazards | $12 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 Sweetwater County's main hazards
- Right now: National Weather Service alerts for Wyoming · all official warnings on Global Incident Tracker.
- Landslide: Landslides recorded
- Winter weather: Power outages now · Carbon monoxide in winter
- Wildfire: US wildfires now · Wildfire smoke: what protects you
- 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 Sweetwater County
What natural disasters is Sweetwater County, Wyoming most at risk from?
Sweetwater County, Wyoming has a Very Low natural-hazard risk rating in FEMA's National Risk Index (v1.20, December 2025): a score of 30.6 out of 100, higher than about 30% of US counties, with landslides, winter storms and wildfires scoring highest of its 18 hazards and $12 million a year in expected losses.
How many federal disaster declarations has Sweetwater County had?
OpenFEMA lists 2 federal disaster declarations that included Sweetwater County since 1977, not counting 2 for COVID-19; the latest is DR-4007-WY (Severe Storms, Flooding, and Landslides, declared 22 July 2011). Another 1 Wyoming declarations were made statewide without a county list.
How many tornadoes have hit Sweetwater County?
NOAA's Storm Prediction Center recorded 26 tornadoes touching Sweetwater 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.