Lewis and Clark County, Montana Storm events, disaster declarations and flood insurance claims on record
This page is a county record of past events and claims. It does not show the flood zone or the risk of an address. For the flood map of an address, use FEMA's address search (opens in a new tab).
NCEI has 317 storm events on record for Lewis and Clark County, Montana, from 1950 through 30 Jun 2026.
The newest event on record is a hail event on 25 Jun 2026.
FEMA has 16 disaster declarations on record for the county from 1964 through 1 Oct 2026. The newest is FM-5507 of 12 Jul 2024.
OpenFEMA has 102 NFIP claims on record for the county from 1978 through 8 Sep 2026. The NFIP paid $432 thousand on these claims.
The NWS collects event reports from a variety of sources, which include (but are not limited to): county, state, and federal emergency management officials, local law enforcement officials, SKYWARN spotters, NWS damage surveys, newspaper clipping services, the insurance industry, and the general public, among others.
The National Weather Service reports property and crop damage estimates using available data at the time of event reporting. These values should therefore be considered broad estimates. Damage amounts are not adjusted for inflation.
Zone (NWS Forecast Zone): A zone is a geographic area defined by the NWS for issuing forecasts, watches, and warnings. While zones often align with counties, they can also represent smaller or subdivided areas within a county to account for differences in weather conditions, such as elevation or proximity to water. Larger-scale events—such as heat, cold, drought, and winter storms—are typically recorded by zone.
The words of the agency. Source: NOAA NCEI, Storm Events Database, page "Frequently Asked Questions", copied on .
This is raw, unedited data from FEMA's National Emergency Management Information System (NEMIS) and as such is subject to a small percentage of human error.
The words of the agency. Source: FEMA, OpenFEMA Dataset "Disaster Declarations Summaries - v2", copied on . The page gives: last data refresh 2026-10-01.
It is derived from the National Flood Insurance Program system of record, staged in the program's reporting platform and redacted to protect policy holder personally identifiable information.
The words of the agency. Source: FEMA, OpenFEMA Dataset "NFIP Redacted Claims - v3", copied on . The page gives: last data refresh 2026-09-09.
Dates of the data: NCEI storm events through . OpenFEMA disaster declarations through . NFIP claims through .
Since the last update: no change is on record for Lewis and Clark County. The site compares the agency data at each update. Updates of the data
The five hazards
| Hazard | 1950 to 2026 | 2000 to 2009 | 2010 to 2019 | 2020 to 2026 | Newest event |
|---|---|---|---|---|---|
| Hail | 118 | 47 | 24 | 11 | |
| Tornado | 4 | 0 | 0 | 0 | |
| Flood | 39 | 12 | 18 | 8 | |
| Wind | 114 | 36 | 17 | 33 | |
| Winter | 0 | 0 | 0 | 0 | None on record |
| Other event types | 42 | Heat, cold, drought, wildfire, lightning, fog, tropical and other types | |||
| All storm events | 317 | 102 | 65 | 80 | |
A hazard name opens the page of that hazard for the county. A hazard has a page from 10 events. The year 2026 has the events through 30 Jun 2026 only.
A county count has the events that NCEI gives to the county. It also has the events of a forecast zone that has the name of the county. A zone with another name counts for the state only.
| Measure | Lewis and Clark | All counties of Montana | All counties of the United States |
|---|---|---|---|
| Storm events for each 100 square miles, 1950 to 2026 | 9.2 | 16.7 | 49.3 |
| Storm events for each 10,000 residents, 1950 to 2026 | 43.9 | 220.7 | 52.5 |
| NFIP claims for each 1,000 policies in force, 2016 to 2025 | 227.3 | 100.0 | 185.3 |
The columns for the state and the United States total the counties. They count the events of each county in the same way as the county column. The site gives a rate for each 10,000 residents only from 10,000 residents. Residents and area: Census Bureau, 2021.
Newest storm events on record
Hail1.00 in, quarter size
1 mile NW of EAST HELENA
Hail1.00 in, quarter size
2 miles WNW of (HLN)HELENA RGNL ARP
Hail1.00 in, quarter size
1 mile NW of IRON
Thunderstorm Wind59 mph (51 knots, measured gust)
16 miles SE of AUGUSTA ARPT
Thunderstorm Wind58 mph (50 knots, estimated gust)
3 miles SE of IRON. Damage estimate: $1 thousand
Debris Flow
3 miles SSW of CANYON FERRY. Damage estimate: $11 thousand
Thunderstorm Wind60 mph (52 knots, measured gust)
At (HLN)HELENA RGNL ARP
Thunderstorm Wind59 mph (51 knots, measured gust)
16 miles SE of AUGUSTA ARPT
Thunderstorm Wind61 mph (53 knots, measured gust)
16 miles SE of AUGUSTA ARPT
Thunderstorm Wind61 mph (53 knots, measured gust)
At (HLN)HELENA RGNL ARP
Thunderstorm Wind62 mph (54 knots, measured gust)
At (HLN)HELENA RGNL ARP
Flash Flood
1 mile NNW of CANYON FERRY
Thunderstorm Wind63 mph (55 knots, measured gust)
2 miles ENE of (HLN)HELENA RGNL ARP
Thunderstorm Wind61 mph (53 knots, measured gust)
16 miles SE of AUGUSTA ARPT
Thunderstorm Wind61 mph (53 knots, estimated gust)
2 miles NNE of HOLTER DAM
Thunderstorm Wind59 mph (51 knots, measured gust)
4 miles SE of SIEBEN
Thunderstorm Wind58 mph (50 knots, estimated gust)
4 miles N of IRON
Thunderstorm Wind62 mph (54 knots, measured gust)
At BROADWATER
Thunderstorm Wind62 mph (54 knots, measured gust)
1 mile SSE of SILVER CITY
Hail1.00 in, quarter size
3 miles WNW of MARYSVILLE
Hail1.50 in, ping-pong ball size
1 mile SSE of SILVER CITY
Thunderstorm Wind59 mph (51 knots, measured gust)
At (HLN)HELENA RGNL ARP
Thunderstorm Wind59 mph (51 knots, measured gust)
At (HLN)HELENA RGNL ARP
Thunderstorm Wind67 mph (58 knots, measured gust)
16 miles SE of AUGUSTA ARPT
Thunderstorm Wind58 mph (50 knots, measured gust)
16 miles SE of AUGUSTA ARPT
The 25 events above are the newest in the NCEI record. A place is the text of the NCEI record: a distance and a direction from a reference place. Wind speed is in miles per hour, with the knots that NCEI gives. The site does not show a place text that names a private property or reads as a person. Download these events (CSV)
| Decade | Year that ends in 0 | Year that ends in 1 | Year that ends in 2 | Year that ends in 3 | Year that ends in 4 | Year that ends in 5 | Year that ends in 6 | Year that ends in 7 | Year that ends in 8 | Year that ends in 9 | All |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1950s | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 1 | 0 | 1 | 4 |
| 1960s | 1 | 0 | 0 | 0 | 2 | 0 | 1 | 0 | 0 | 0 | 4 |
| 1970s | 1 | 0 | 0 | 0 | 1 | 6 | 1 | 0 | 0 | 0 | 9 |
| 1980s | 0 | 0 | 8 | 0 | 3 | 1 | 0 | 0 | 3 | 8 | 23 |
| 1990s | 3 | 4 | 3 | 0 | 1 | 1 | 4 | 7 | 4 | 3 | 30 |
| 2000s | 11 | 20 | 10 | 9 | 9 | 8 | 4 | 10 | 17 | 4 | 102 |
| 2010s | 4 | 4 | 5 | 8 | 6 | 0 | 2 | 12 | 15 | 9 | 65 |
| 2020s | 19 | 2 | 28 | 8 | 12 | 8 | 3 (part of the year) | 80 |
A darker cell has a larger count. The number is in each cell.
NCEI recorded tornado events from 1950, and hail and thunderstorm wind events from 1955. It recorded all event types from 1996. A count before 1996 has fewer event types.
FEMA disaster declarations
FEMA has 16 disaster declarations on record for Lewis and Clark County from 1964 through 1 Oct 2026. The newest is FM-5507: HORSE GULCH FIRE.
| Declared | Number | Type | Incident type | Title in the FEMA record | Assistance |
|---|---|---|---|---|---|
| FM-5507 | Fire management assistance | Fire | HORSE GULCH FIRE | Public | |
| DR-4508 | Major disaster | Biological | COVID-19 PANDEMIC | Individual, Public | |
| EM-3476 | Emergency | Biological | COVID-19 | Public | |
| FM-5286 | Fire management assistance | Fire | NORTH HILLS FIRE | Public | |
| DR-4405 | Major disaster | Flood | FLOODING | Public | |
| FM-5208 | Fire management assistance | Fire | ALICE CREEK FIRE | Public | |
| FM-2987 | Fire management assistance | Fire | CORRAL FIRE | Public | |
| DR-1996 | Major disaster | Severe Storm | SEVERE STORMS AND FLOODING | Individual, Public | |
| FM-2730 | Fire management assistance | Fire | COUNTRY CLUB FIRE | Public | |
| EM-3253 | Emergency | Hurricane | HURRICANE KATRINA EVACUATION | Public | |
| FM-2492 | Fire management assistance | Fire | MT-LINCOLN FIRE COMPLEX - 08/14/2003 | Public | |
| DR-1340 | Major disaster | Fire | WILDFIRES | Individual | |
| FM-2314 | Fire management assistance | Fire | MT - CENTRAL ZONE 3B FIRE COMPLEX | Public | |
| DR-1105 | Major disaster | Severe Storm | SEVERE STORMS, FLOODING, AND ICE JAMS | Public | |
| DR-640 | Major disaster | Flood | SEVERE STORMS & FLOODING | Individual, Public | |
| DR-472 | Major disaster | Flood | RAINS, SHOWMELT, STORMS & FLOODING | Individual, Public |
DR is a major disaster declaration. EM is an emergency declaration. FM is a fire management assistance declaration. A declaration for the whole state is on the Montana page. What a disaster declaration is
The dataset includes declared recovery programs and geographic areas (county not available before 1964; Fire Management records are considered partial due to historical nature of the dataset).
Flood insurance claims (NFIP)
OpenFEMA has 102 NFIP claims on record for Lewis and Clark County from 1978 through 8 Sep 2026.
The NFIP paid $431,718 on 78 claims.
The county has 227.3 NFIP claims for each 1,000 policies in force. The rate uses 40 claims with a year of loss from 2016 to 2025. FEMA counts 176 residential policies in force on 3 Aug 2026. The claims have every type of building. FEMA counts residential policies only.
| Decade | Year that ends in 0 | Year that ends in 1 | Year that ends in 2 | Year that ends in 3 | Year that ends in 4 | Year that ends in 5 | Year that ends in 6 | Year that ends in 7 | Year that ends in 8 | Year that ends in 9 | All |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1970s | 3 | 3 | 6 | ||||||||
| 1980s | 2 | 14 | 1 | 2 | 0 | 0 | 6 | 0 | 0 | 0 | 25 |
| 1990s | 0 | 0 | 0 | 0 | 0 | 0 | 7 | 1 | 1 | 0 | 9 |
| 2000s | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 |
| 2010s | 1 | 17 | 0 | 0 | 3 | 0 | 0 | 0 | 38 | 1 | 60 |
| 2020s | 0 | 0 | 0 | 0 | 1 | 0 | 0 (part of the year) | 1 |
A darker cell has a larger count. The number is in each cell.
NFIP claims by year of loss with the amount paid: 17 years
| Year of loss | Claims | Claims with a payment | Amount paid |
|---|---|---|---|
| 2024 | 1 | not shown | not shown |
| 2019 | 1 | not shown | not shown |
| 2018 | 38 | 31 | $175,800 |
| 2014 | 3 | not shown | not shown |
| 2011 | 17 | 12 | $93,507 |
| 2010 | 1 | not shown | not shown |
| 2009 | 1 | not shown | not shown |
| 1998 | 1 | not shown | not shown |
| 1997 | 1 | not shown | not shown |
| 1996 | 7 | not shown | not shown |
| 1986 | 6 | 6 | $8,977 |
| 1983 | 2 | not shown | not shown |
| 1982 | 1 | not shown | not shown |
| 1981 | 14 | 13 | $112,600 |
| 1980 | 2 | not shown | not shown |
| 1979 | 3 | not shown | not shown |
| 1978 | 3 | not shown | not shown |
A year with fewer than 5 claims shows the count of claims and no amount. A year with 1 to 4 claims with a payment shows no amount either. Such an amount could point to one property. The amount is the sum of the building, contents and increased cost of compliance payments. FEMA counts 5 multiple-loss properties in the county (2 Aug 2026). How FEMA redacts NFIP claims
This dataset is not intended to be an official federal report, and should not be considered an official federal report.
Note, the County Code field may not reflect the individual county the property is located as projects can be associated with more than one county
FEMA cannot verify the quality and/or timeliness of any data or any analysis derived therefrom after the data has been retrieved from FEMA.gov.
National Risk Index
- Risk Index rating
- Relatively Low
- Risk Index score
- 71.2 of 100
- Expected Annual Loss rating
- Relatively Low
- Expected Annual Loss
- $35 million
- Social Vulnerability rating
- Relatively Low
- Community Resilience rating
- Very High
| Hazard type | Risk Index rating | Expected Annual Loss |
|---|---|---|
| Avalanche | Relatively Moderate | $456,670 |
| Cold wave | Relatively High | $12,893,215 |
| Drought | Very Low | $9,009 |
| Earthquake | Relatively Low | $3,795,774 |
| Hail | Very Low | $38,203 |
| Heat wave | Very Low | $213,047 |
| Ice storm | Very Low | $11,961 |
| Inland flooding | Relatively Low | $12,360,093 |
| Landslide | Relatively Moderate | $154,163 |
| Lightning | Relatively Moderate | $504,410 |
| Strong wind | Relatively Low | $225,718 |
| Tornado | Very Low | $62,292 |
| Wildfire | Relatively Moderate | $2,546,506 |
| Winter weather | Very High | $1,567,054 |
The National Risk Index dataset leverages available source data for natural hazard and community risk factors to develop a baseline relative risk measurement for each United States county and Census tract.
The rating is a qualitative categorization that describes the community in comparison to all other communities at the same level, ranging from “Very Low” to “Very High.”
The National Risk Index data are meant for planning purposes only.
The labels and the ratings are those of FEMA. Expected Annual Loss is a figure for a whole county. It is not a figure for a property. How to read the National Risk Index
Tropical storm and hurricane tracks
The HURDAT2 record of the National Hurricane Center goes through the 2025 season. It has no track at tropical storm strength within 100 miles of the centre point of Lewis and Clark County.
ZIP Codes, cities and towns of Lewis and Clark County
Each ZIP Code below has a page with its NFIP claims by year. 1 more ZIP Code has fewer than 5 claims and no page.
A city or town has no page of its own. This page is the record for the whole county, which has these places:
- Augusta
- Canyon Creek
- Craig
- East Helena
- Gilman
- Helena
- Helena Valley Northeast
- Helena Valley Northwest
- Helena Valley Southeast
- Helena Valley West Central
- Helena West Side
- Lincoln
- Marysville
- Milford Colony
- Rimini
- Unionville
- Wolf Creek
- York
Official channels
- FEMA Flood Map Service Center: Search By Address (opens in a new tab)Search an address to see its flood map. This site has no flood-zone data.
- National Weather Service: Great Falls, MT (opens in a new tab)The forecast office that issues the weather warnings for the county.
- Montana Disaster and Emergency Services (opens in a new tab)The emergency management agency of the state.
- NCEI Storm Events Database (opens in a new tab)Search the full NCEI record by state, county and date.
These links open the pages of the agencies. The site checked the links on .
Cite this page
County Hazards. "Lewis and Clark County, Montana: storm events, disaster declarations and flood insurance claims on record". https://countyhazards.com/county/mt/lewis-and-clark/. Data: NOAA NCEI Storm Events Database through 30 Jun 2026; FEMA OpenFEMA disaster declarations through 1 Oct 2026; FEMA OpenFEMA NFIP claims through 8 Sep 2026. Page made on .
Where the data comes from
- Storm events: NOAA NCEI Storm Events Database, yearly details files through 30 Jun 2026.
- Disaster declarations: OpenFEMA Disaster Declarations Summaries, read on 1 Oct 2026.
- NFIP claims: OpenFEMA NFIP Claims, as of 8 Sep 2026. Multiple-loss properties: 2 Aug 2026. Policies in force: 3 Aug 2026.
- National Risk Index: FEMA, December 2025 release. Storm tracks: NHC HURDAT2 through the 2025 season.
- Residents, area, places and adjacent counties: US Census Bureau, 2021 vintage.
How the counts are made · Corrections · Hazards in all states: hail, tornado, flood, wind, winter
Questions
- How many tornado events are on record for Lewis and Clark County?
- NCEI has 4 tornado events on record for Lewis and Clark County from 1950 through 30 Jun 2026. No event has a rating of EF2 or F2, or a higher rating.
- How large is the hail on record for Lewis and Clark County?
- NCEI has 118 hail events on record from 1955 through 30 Jun 2026. 27 events have a hail size of 1.75 inches or more. NCEI names 1.75 inches a golf ball.
- Which month has the most storm events on record for Lewis and Clark County?
- June has 98 of the 317 storm events on record from 1950 through 30 Jun 2026.
- How many NFIP claims are there for each 1,000 policies in force in Lewis and Clark County?
- The county has 227.3 NFIP claims for each 1,000 policies in force. The rate uses 40 claims with a year of loss from 2016 to 2025. FEMA counts 176 residential policies in force on 3 Aug 2026. The claims have every type of building. FEMA counts residential policies only.