Campbell County, Wyoming

What hazards hit Campbell County most?

The most frequent records are hail reports: 591 since 1958. 71% of its hail reports since 1958 fell in June and July. The rank column places the county among Wyoming'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 Campbell County had?

NOAA records 93 tornadoes in Campbell County from 1953 to 2026, the strongest rated EF3, with 2 deaths and 32 injuries recorded in the county. That is 4th of 23 Wyoming 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 95 tornadoes whose track touched Campbell County since 1950 (NOAA's county records number 93: they file a crossing tornado once per county segment, and the two databases differ on some tracks); along their whole tracks they killed 2 people.

Map of the strongest tornado tracks in Wyoming.

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 Campbell County?

The most recent record with damage, injuries or deaths is the June 23, 2023 tornado (8 injuries).

A tornado developed near the Campbell-Converse County line southeast of Wright, where it snapped wooden power poles and tipped over several empty train cars. It struck the operations area of the North Antelope Rochelle Coal Mine, ripping metal roofs and wall panels from shop buildings; moving and flipping cars, buses, and shipping containers; and overturning empty railroad cars. Damage severity indicated wind gusts were as high as 120 to 130 mph. No track was visible across the vegetation. Seven people sustained mostly minor injuries at the mine. The tornado continued into southwestern Weston County.
National Weather Service event narrative, NOAA Storm Events Database (search the full record, event 1103685)

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

A damage figure marked "step" is a record from before 1993: NOAA then filed damage by category, and the figure is the category as entered, in the dollars of that year, not an estimate of the loss.

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 Campbell 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).

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

What time of year?

71% of its hail reports since 1958 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 Campbell County

FEMA's register lists 6 declarations that include Campbell County: 4 major disasters, 2 emergencies and 0 fire management assistance declarations. Most were for biological (2) and fire (1).

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 Campbell County had?

NOAA's Storm Events Database holds 26 flood or flash flood records for Campbell County from 1996 to 2019, on 21 days, with 1 death. By flood insurance claims since 1978 (OpenFEMA, as of September 8, 2026), Campbell County ranks 2061st of 2,942 U.S. counties.

The National Flood Insurance Program has paid $38,000 on 22 claims filed in Campbell County; the most in one year was 12 in 1978. 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 Campbell County

FEMA's National Risk Index rates Campbell County Relatively Low overall, with an expected annual loss of $25.0 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 Campbell County

1. Campbell County 1,488
2. Crook County 1,309
3. Weston County 911
4. Converse County 843
5. Sheridan County 815
6. Johnson County 750
7. Powder River County, MT 703

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 WyomingEvery Wyoming tornado since 1950 and the counties with the most per square mile
• Hail in WyomingThe state's hail reports, by county, year and month
• The Wyoming recordEvery hazard in the state, its deadliest events and its federal declarations
• FEMA's risk rating for each hazard in Campbell CountyThe hazard risk calculator: 18 hazards beside the county's record
• Download Campbell County's FEMA declarations (CSV)6 rows: every declaration that named the county, for your own analysis