Lewis and Clark County, MT
FEMA National Risk Index scores, disaster declarations & hazard data
Lewis and Clark County has experienced 16 federally declared disasters since 1975, most recently Horse Gulch Fire in 2024. Its overall natural hazard risk is rated Relatively Low — lower risk than most US counties.
Lewis and Clark County's highest-rated hazards are winter weather, landslide, and cold wave, with its top risk rated "Very High" by FEMA's National Risk Index. Recorded storm events have decreased 18% over the past five years compared to the prior five-year period. Community vulnerability is relatively low (19th percentile nationally), indicating stronger recovery capacity than most US counties.
Past disasters & FEMA designations
A federal disaster declaration officially designates a county for FEMA disaster assistance. Lewis and Clark County has been designated in 16 declarations since 1975, covering 5 disaster types including fire (8), flood (3), biological (2).
| Year | Type | Event name |
|---|---|---|
| 2024 | Fire | Horse Gulch Fire |
| 2020 | Biological | Covid-19 Pandemic |
| 2020 | Biological | Covid-19 |
| 2019 | Fire | North Hills Fire |
| 2019 | Flood | Flooding |
| 2017 | Fire | Alice Creek Fire |
| 2012 | Fire | Corral Fire |
| 2011 | Severe Storm | Severe Storms And Flooding |
| 2007 | Fire | Country Club Fire |
| 2005 | Hurricane | Hurricane Katrina Evacuation |
Showing the 10 most recent of 16 total declarations since 1975.
Source: FEMA OpenFEMA Disaster Declarations Summaries. A single disaster can produce more than one record per county. Data current through September 2026.
Risk by hazard type
| Hazard | Risk rating | Risk score | Recorded events | Deaths | Prop. damage |
|---|---|---|---|---|---|
| Wildfire | Relatively Moderate | 92.8 | 0 | 0 | — |
| Inland Flooding | Relatively Low | 64.6 | 21 | 0 | $800K |
| Coastal Flooding | Not Applicable | — | 0 | 0 | — |
| Earthquake | Relatively Low | 86.8 | 37 | — | — |
| Heat Wave | Very Low | 35.4 | 0 | 0 | — |
| Tornado | Very Low | 8.9 | 0 | 0 | — |
| Hurricane | Not Applicable | — | 0 | 0 | — |
| Hail | Very Low | 10.2 | 15 | 0 | — |
| Strong Wind | Relatively Low | 21.2 | 0 | 0 | — |
| Winter Weather | Very High | 98.1 | 0 | 0 | — |
| Ice Storm | Very Low | 15.7 | — | — | — |
| Cold Wave | Relatively High | 94.6 | — | — | — |
| Lightning | Relatively Moderate | 66.3 | 2 | 0 | — |
| Drought | Very Low | 22.8 | 0 | 0 | — |
| Landslide | Relatively Moderate | 95.2 | 2 | 0 | $16K |
| Avalanche | Relatively Moderate | 79.8 | — | — | — |
| Tsunami | Not Applicable | — | — | — | — |
| Volcanic Activity | Not Applicable | — | — | — | — |
Scores are 0–100 percentiles relative to all US counties — higher means more exposed, not that a disaster is likely this year. Event counts: NOAA Storm Events 2016–2026; earthquake counts from USGS ComCat (M3.0+, 1996–2026). See the methodology page for details.
Community vulnerability
Lewis and Clark County ranks in the 19th percentile (Very low) for community vulnerability — a measure of how hard disaster impacts tend to hit residents. Higher vulnerability means more displacement, worse health outcomes, and slower recovery after a disaster.
| SVI theme | Percentile | Vulnerability level |
|---|---|---|
| Overall | 19th | Very low |
| Socioeconomic status | 18th | Very low |
| Household characteristics | 13th | Very low |
| Racial & ethnic minority status | 30th | Low |
| Housing type & transportation | 45th | Low |
Source: CDC/ATSDR Social Vulnerability Index 2022. Percentiles compare counties nationally — higher means more vulnerable relative to other counties. See CDC SVI for full methodology.
Future risk outlook
| Wildfire metric | National percentile | Level |
|---|---|---|
| Burn probability | 88th | Very High |
| Risk to homes | 91st | Very High |
| Buildings in direct exposure zone | 46.2% | — |
NOAA tracked 40 weather events in this county over 2016–2025: 22 in 2016–20 vs 18 in 2021–25 (-18% — frequency decreasing).
Wildfire: USDA Forest Service Wildfire Risk to Communities (RDS-2020-0016-2) — modeled values, not annual forecasts. See wildfirerisk.org. Inland flood and heat projections pending data availability; coastal sea-level projections are available for select coastal counties below — see the data page.
Nearby counties
Frequently asked questions
What natural hazards pose the greatest risk in Lewis and Clark County?
According to the FEMA National Risk Index, the highest-risk hazards in Lewis and Clark County, Montana are winter weather, landslide, and cold wave. The county's overall natural hazard risk is rated Relatively Low — lower risk than most US counties.
Has Lewis and Clark County received federal disaster declarations?
Yes. Lewis and Clark County has received 16 federal disaster declarations since 1975, including declarations in 2024. The most common disaster type on record is fire (8 declarations).
Has Lewis and Clark County had any FEMA disaster declarations in 2024, 2025, or 2026?
Yes. Recent federal disaster declarations for Lewis and Clark County include Horse Gulch Fire (2024). See the declarations table above for the full history since 1975.
How does Lewis and Clark County's natural hazard risk compare to nearby counties?
Among neighboring counties, Cascade County, MT has the highest overall natural hazard risk (Relatively Moderate) and Granite County, MT has the lowest (Very Low). Lewis and Clark County is rated Relatively Low overall.
How is Lewis and Clark County's composite disaster risk index calculated?
Lewis and Clark County's composite disaster risk index — officially FEMA's National Risk Index (NRI) — scores every US county on a 0–100 percentile scale across 18 natural hazard types, factoring in expected annual loss, social vulnerability, and community resilience. Lewis and Clark County's composite score of 71 means its overall natural hazard risk is higher than 71% of US counties.