Valley County, Montana

What hazards hit Valley County most?

The most frequent records are severe thunderstorm wind events: 577 since 1956. 69% of its severe thunderstorm wind events since 1956 fell in June and July. The rank column places the county among Montana's counties by days with a record per 1,000 square miles of land over each hazard's complete period.

Source: NOAA NCEI Storm Events Database (county and forecast-zone records attributed to the county; a zone record shows its own totals on each county it covers). Days: dates with at least one record of the hazard in the county. Ranks: days with a record per 1,000 square miles of land (Census Bureau 2024 Gazetteer), since 1950 for tornadoes, 1955 for hail and thunderstorm wind, 1996 for the rest.

How many tornadoes has Valley County had?

NOAA records 44 tornadoes in Valley County from 1954 to 2024, the strongest rated EF2, with 0 deaths and 0 injuries recorded in the county. That is 5th of 56 Montana counties by days with tornadoes per 1,000 square miles since 1950. A tornado that crossed a county line is counted in each county it touched, with the length of its path inside the county.

Counted as whole tornadoes rather than county records, the Storm Prediction Center's database holds 44 tornadoes whose track touched Valley County since 1950 (NOAA's county records number 44, the same count); along their whole tracks they killed 0 people.

Map of the strongest tornado tracks in Montana.

Source: NOAA NCEI Storm Events Database, tornado records by county (path length in the county, maximum width); ratings as published: F scale before February 1, 2007, EF scale after. Whole-track figures: NOAA Storm Prediction Center tornado database (1950-2025). SPC severe weather database.

When was the last damaging storm in Valley County?

The most recent record with damage, injuries or deaths is the June 18, 2016 thunderstorm wind ($31,000 in damage in 2025 dollars).

Public reported 7 power poles blown down along MT Highway 24.
National Weather Service event narrative, NOAA Storm Events Database (search the full record, event 645915)

Source: NOAA NCEI Storm Events Database; every record of 2025-2026 is listed, earlier ones when they caused deaths, injuries or $250,000 of damage (2025 dollars), and every tornado.

The deadliest and costliest records

Source: NOAA NCEI Storm Events Database: deaths and injuries direct and indirect; damage is property plus crops as estimated by the National Weather Service, converted to 2025 dollars.

Is it getting more frequent?

Records per decade for Valley County's most frequent hazards. Counts rose everywhere after 1996, when NOAA began recording every event type, so compare decades within a hazard's complete period only (the shaded cells come before it).

Drought in the 2010s: 22 records against 7 in the decade before, 22 of them forecast-zone records. Drought in the 2020-26: 72 records against 22 in the decade before, 72 of them forecast-zone records. Cells marked z rose mostly through zone records. The local National Weather Service office files these once per forecast zone, so a change in how it draws its zones or splits a storm into records moves this count as much as the weather does; read it beside the Valley County days with a record above.

Source: NOAA NCEI Storm Events Database, records per calendar decade; zone records from the CZ_TYPE field (Z).

What time of year?

69% of its severe thunderstorm wind events since 1956 fell in June and July. The two busiest months are in violet.

Source: NOAA NCEI Storm Events Database, records by the month they began.

Federal disaster declarations for Valley County

FEMA's register lists 13 declarations that include Valley County: 11 major disasters, 2 emergencies and 0 fire management assistance declarations. Most were for flood (6) and severe storm (3).

Source: FEMA OpenFEMA Disaster Declarations Summaries (v2), declarations through October 2, 2026; one declaration is counted once however many areas it names. OpenFEMA dataset page.

How many floods has Valley County had?

NOAA's Storm Events Database holds 123 flood or flash flood records for Valley County from 1996 to 2024, on 85 days, with 0 deaths. By flood insurance claims since 1978 (OpenFEMA, as of September 8, 2026), Valley County ranks 827th of 2,942 U.S. counties.

The National Flood Insurance Program has paid $1.5 million on 250 claims filed in Valley County; the most in one year was 92 in 2011. Claims count insured losses only: uninsured flood damage is not in this file.

Source: FEMA OpenFEMA NFIP Redacted Claims, as of September 8, 2026; claims by year of loss, payments in the dollars of the year paid. OpenFEMA dataset page.

FEMA's modeled risk for Valley County

FEMA's National Risk Index rates Valley County Very Low overall, with an expected annual loss of $11.2 million. These are FEMA's model estimates of future loss from 18 hazards, not a count of what happened; they can differ from the record above.

Source: FEMA National Risk Index, county table, December 2025 release. FEMA's National Risk Index map.

Counties that share a border with Valley County

1. Valley County 1,841
2. Phillips County 1,330
3. Roosevelt County 1,151
4. Garfield County 885
5. McCone County 748
6. Daniels County 528

Source: U.S. Census Bureau county adjacency file; NOAA NCEI Storm Events Database, records since 1950. The Census Bureau's adjacency file.

Next

• Tornadoes in MontanaEvery Montana tornado since 1950 and the counties with the most per square mile
• Severe thunderstorm wind in MontanaThe state's severe thunderstorm wind events, by county, year and month
• The Montana recordEvery hazard in the state, its deadliest events and its federal declarations
• FEMA's risk rating for each hazard in Valley CountyThe hazard risk calculator: 18 hazards beside the county's record
• Download Valley County's FEMA declarations (CSV)13 rows: every declaration that named the county, for your own analysis