Lake County, Montana
Natural disaster risk, federal disaster history and flood insurance facts.
Lake County, Montana has a relatively low overall risk from natural hazards in FEMA's National Risk Index. Its risk score is higher than 68% of US counties. It ranks 8th of 56 counties in Montana. The costliest hazards here are inland flooding, earthquakes and cold waves. FEMA estimates about $23 million a year in expected losses, or roughly $741 per resident. Since 2000 it has been included in 6 federal disaster or emergency declarations for natural events (4 major disasters). The most recent was in April 2026 (severe winter storm and straight-line winds). Only 30 homes here carry federal flood insurance. Since 1978, federal flood insurance has paid about $20,000 on 12 claims here.
FEMA National Risk Index December 2025; OpenFEMA declarations to Nov 6, 2026; NFIP records. Updated November 6, 2026.
Top risks in Lake County
- Check the FEMA flood map for your address, and ask the seller or landlord about past flooding.
- Price a flood policy now. Most new federal policies take 30 days to start.
- Ask whether an older house is bolted to its foundation.
- Consider separate earthquake insurance where risk is high.
- Insulate pipes in outside walls, crawl spaces and garages.
- Know how to shut off the main water valve.
All 18 hazards
What the ratings mean ›| Hazard | Rating | Score | Expected loss a year | |
|---|---|---|---|---|
| Inland flooding | 57.2 | $7M | ||
| Earthquake | 92.3 | $7M | ||
| Cold wave | 85.8 | $5M | ||
| Wildfire | 92.7 | $2M | ||
| Avalanche | 91.4 | $2M | ||
| Winter weather | 94.4 | $532K | ||
| Ice storm | 72.7 | $220K | ||
| Heat wave | 38.7 | $184K | ||
| Lightning | 37.2 | $125K | ||
| Strong wind | 11.5 | $75K | ||
| Landslide | 90.8 | $53K | ||
| Hail | 11.2 | $31K | ||
| Drought | 24.0 | $8K | ||
| Tornado | 3.3 | $7K |
Scores are percentiles: a score of 90 means higher risk than about 90% of US counties for that hazard. Hazards FEMA does not rate here are left out. Social vulnerability is relatively moderate and community resilience is relatively moderate in FEMA's measures.
Federal disaster history
Recent disasters nationwide ›Declarations by decade
Federal declarations for natural events that included Lake County. 2020s bar runs to November 2026.
By type
Most recent
Montana also had 36 statewide declarations that did not name single counties.
Storm history since 1961
Tornado risk by county ›The National Weather Service has logged 112 storm reports in Lake County since 1961 and about $959,300 in reported damage. The strongest on record here was an F0 tornado on March 3, 1991.
Strongest tornadoes
| Date | Strength | Near | Hurt / killed |
|---|---|---|---|
| Mar 3, 1991 | F0 | – | 0 / 0 |
| Jul 18, 2007 | EF0 | Pablo | 0 / 0 |
| May 9, 2023 | EF0 | St Ignatius Arpt | 0 / 0 |
| Sep 1, 2011 | EF0 | Polson Arpt | 0 / 0 |
Most damaging storms
| Date | Type | Near | Damage |
|---|---|---|---|
| May 31, 1993 | Thunderstorm Wind | Swan Lake | $500K |
| Jul 6, 2009 | Lightning | St Ignatius | $140K |
| May 15, 1994 | Thunderstorm Wind | Swan Lake | $50K |
| Jun 28, 2022 | Thunderstorm Wind | Moiese | $50K |
| Jul 9, 2022 | Hail | Rollins | $44K |
| Jul 18, 2007 | Thunderstorm Wind | Pablo | $30K |
Source: NOAA Storm Events Database, county-based reports through Jun 29, 2026. Tornado records start in 1950, hail and wind in 1955, and floods and other storm types in 1996, so older decades undercount. Damage is in dollars of the year it happened and is often an estimate. Winter storms, heat and hurricanes are logged by forecast zone, not county, so they are not counted here.
Flood insurance in Lake County
Check your address flood zone ›National Flood Insurance Program (NFIP) records only; private flood policies are not included. Home counts as of Aug 3, 2026. Since 2021 NFIP prices each home separately under Risk Rating 2.0, so your price depends on the building, not the county. Ask an agent for a quote.
Homes in Lake County
Older homes and mobile homes usually suffer more damage in storms, floods and earthquakes, and can cost more to insure. If you are buying, ask about roof age, foundation bolting and any retrofits. Source: US Census Bureau, American Community Survey 2020 to 2024 5-year estimates; 16,468 housing units.
Compare in Montana
All 56 ›| Largest counties | Overall risk | Top hazard |
|---|---|---|
| Yellowstone County | Inland flooding | |
| Gallatin County | Earthquake | |
| Missoula County | Inland flooding | |
| Flathead County | Inland flooding | |
| Cascade County | Inland flooding | |
| Lewis and Clark County | Cold wave | |
| Ravalli County | Wildfire | |
| Silver Bow County | Cold wave |
Neighboring counties
| County | Overall risk | Declarations |
|---|---|---|
| Missoula County | 19 | |
| Flathead County | 13 | |
| Sanders County | 14 |
Common questions about Lake County
What is the biggest natural hazard in Lake County?
Inland flooding has the highest expected yearly losses in Lake County, about $7.1 million a year in FEMA's estimate. Earthquake is second at $6.6 million.
How many federal disasters has Lake County had?
Lake County has been included in 6 federal disaster or emergency declarations for natural events since 2000, including 4 major disasters. The most recent was Severe Winter Storm and Straight-Line Winds in April 2026.
Is Lake County a high-risk place to live?
Its overall rating is Relatively Low, 8th highest of 56 in Montana. A county rating covers the whole area. Risk at one address can be much higher or lower, so check the FEMA flood map and ask about the home's history.
Do I need flood insurance in Lake County?
Standard home insurance does not cover flooding. About 1 in 500 homes in Lake County has federal flood insurance. Lenders require it in mapped high-risk zones, but many flood claims come from outside those zones.
How many tornadoes has Lake County had?
NOAA records list 4 tornadoes in Lake County since 1950. The strongest was an F0 tornado on March 3, 1991. The weather service has also logged 48 hail reports and 4 floods here.
Sources: FEMA National Risk Index (December 2025), OpenFEMA Disaster Declarations Summaries, and NFIP policy and claims data. Hazard Compass is independent and not affiliated with FEMA. These figures describe the whole county, not a single property, and are not insurance or safety advice. Report a problem.