Larimer County, Colorado: Natural Disaster Risk and History
Larimer County, Colorado has a Relatively Moderate natural-hazard risk rating in FEMA's National Risk Index (v1.20, December 2025): a score of 90.1 out of 100, higher than about 90% of US counties, with lightning, hail and winter storms scoring highest of its 18 hazards and $127 million a year in expected losses.
OpenFEMA lists 28 federal disaster declarations that included Larimer County since 1965, not counting 2 for COVID-19; the latest is FM-5525-CO (Stone Mountain Fire, declared 31 July 2024). NOAA's Storm Prediction Center recorded 33 tornadoes touching Larimer County from 1950 to 2025.
Live weather alerts for Colorado All official warnings Latest FEMA declarations
Population 358,792 Buildings worth $72 billion Area 2,661 sq mi Risk rank in Colorado 7 of 64 FIPS 08069
All 18 hazards, highest risk first
FEMA National Risk Index| Hazard | Risk rating | Score | Expected loss a year | How often | Events in record |
|---|---|---|---|---|---|
| Lightning | Very High | 99.2 | $6.9 million | about 57 a year | 453,215 strikes |
| Hail | Relatively High | 98.3 | $11 million | about 4.4 a year | 167 |
| Winter weather | Very High | 97.9 | $1.8 million | about 22 a year | 422 |
| Wildfire | Relatively High | 97.7 | $15 million | about once every 227 years | — |
| Landslide | Relatively Moderate | 97.2 | $491,433 | about 1.1 a year | — |
| Cold wave | Relatively High | 94.8 | $16 million | about once every 1.8 years | 11 |
| Avalanche | Relatively High | 91.8 | $2.9 million | about once every 5.0 years | 6 |
| Tornado | Relatively High | 90.6 | $11 million | about 1.3 a year | 22 |
| Inland flooding | Relatively Moderate | 89.4 | $54 million | about 2.1 a year | 58 |
| Strong wind | Relatively High | 87.9 | $2.7 million | about once every 1.1 years | 34 |
| Earthquake | Relatively Low | 81.0 | $2.7 million | rarer than once in 1,000 years | — |
| Volcanic activity | Very Low | 62.5 | $69 | rarer than once in 1,000 years | 1 |
| Heat wave | Relatively Low | 58.8 | $817,175 | about once every 5.6 years | 2.2 |
| Ice storm | Relatively Low | 50.9 | $131,809 | about once every 51 years | 1 |
| Drought | Relatively Low | 47.4 | $182,424 | about 18 a year | 784 |
| 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 28
Most common: Fire 15, Flood 7, Severe Storm 2, Snowstorm 2.
| Decade | Declarations | Incident types |
|---|---|---|
| 1960s | 2 | Flood, Tornado |
| 1970s | 2 | Flood ×2 |
| 1980s | 1 | Flood |
| 1990s | 2 | Severe Storm, Flood |
| 2000s | 11 | Fire ×7, Snowstorm ×2, Severe Storm, Coastal Storm |
| 2010s | 6 | Fire ×4, Flood ×2 |
| 2020s | 4 | Fire ×4 |
The last 10
Widest declarations that included Larimer County
- Hurricane Katrina Evacuation (2005, EM-3224-CO): 64 Colorado counties designated.
- Wildfires (2002, DR-1421-CO): 58 Colorado counties designated.
- Snow (2003, EM-3185-CO): 29 Colorado 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. Colorado also had 12 statewide declarations with no county list.
Tornado record since 1950 33
| Tornadoes touching the county | 33 |
|---|---|
| Strongest-rated | (E)F3 ×2 |
| Peak month | June (11) |
| Deadliest | 22 May 2008, EF3, 38.7 mi path, 1 killed, 78 injured |
| Longest path | 22 May 2008, EF3, 38.7 mi path, 1 killed, 78 injured |
| Most recent | 18 May 2018, EF0 |
| Deaths / injuries on those paths | 1 / 78 |
| Rating | (E)F0 | (E)F1 | (E)F2 | (E)F3 | (E)F4 | (E)F5 | Unrated |
|---|---|---|---|---|---|---|---|
| Count | 16 | 12 | 3 | 2 | 0 | 0 | 0 |
| Decade | 1950s | 1960s | 1970s | 1980s | 1990s | 2000s | 2010s | 2020s |
|---|---|---|---|---|---|---|---|---|
| Count | 3 | 2 | 2 | 10 | 11 | 3 | 2 | 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 Larimer County compares with its 5 nearest counties
| County | Distance | Overall risk | Score | Top hazard |
|---|---|---|---|---|
| Larimer County (this page) | — | Relatively Moderate | 90.1 | Lightning |
| Boulder County | 65 km | Relatively Moderate | 90.7 | Lightning |
| Jackson County | 74 km | Very Low | 11.8 | Avalanche |
| Grand County | 84 km | Relatively Low | 50.2 | Avalanche |
| Broomfield County | 87 km | Very Low | 34.7 | Hail |
| Gilpin County | 90 km | Very Low | 6.4 | Wildfire |
Nearest by distance between county centres. Every county in Colorado, ranked.
Vulnerability and resilience
| Social vulnerability | Very Low 10.6 |
|---|---|
| Community resilience | Relatively High 71.3 |
| Community risk factor | 0.70 |
| Expected annual loss, all hazards | $127 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 Larimer County's main hazards
- Right now: National Weather Service alerts for Colorado · all official warnings on Global Incident Tracker.
- Lightning: Weather alerts for Colorado
- Hail: Weather alerts for Colorado
- Winter weather: Power outages now · Carbon monoxide in winter
- 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 Larimer County
What natural disasters is Larimer County, Colorado most at risk from?
Larimer County, Colorado has a Relatively Moderate natural-hazard risk rating in FEMA's National Risk Index (v1.20, December 2025): a score of 90.1 out of 100, higher than about 90% of US counties, with lightning, hail and winter storms scoring highest of its 18 hazards and $127 million a year in expected losses.
How many federal disaster declarations has Larimer County had?
OpenFEMA lists 28 federal disaster declarations that included Larimer County since 1965, not counting 2 for COVID-19; the latest is FM-5525-CO (Stone Mountain Fire, declared 31 July 2024). Another 12 Colorado declarations were made statewide without a county list.
How many tornadoes have hit Larimer County?
NOAA's Storm Prediction Center recorded 33 tornadoes touching Larimer County from 1950 to 2025. The deadliest: 22 May 2008, EF3, 38.7 mi path, 1 killed, 78 injured (deaths and injuries are for the whole path).
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.