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Big Horn County, Wyoming severe weather history spans 222 recorded events between 1958 and 2025. The dominant hazard is thunderstorm wind, accounting for 39.2% of all recorded events. It ranks #2,306 nationally and #15 in Wyoming.
222
Recorded events
1
Direct deaths
3
Direct injuries
$3.1M
Property damage
The record
What the Big Horn County, Wyoming severe weather history record shows
Across the archive, Big Horn County, Wyoming severe weather history averages 3.3 recorded events a year. The busiest stretch on record is the 2010s, with 78 events logged in that decade alone. Roughly 26 events fall before 1990 and 196 from 1990 onward — a gap that reflects the expansion of NOAA reporting practice as much as the weather itself.
The deadliest hazard in the Big Horn County, Wyoming record is tornado, responsible for 1 direct deaths. The costliest is flood, with $2.2M in reported property damage. In total, 7 distinct hazard types appear in this county archive, each listed with its own dated record below.
By hazard type
Every hazard type recorded in Big Horn County
| Hazard | Events | Deaths | Damage | Max | Span |
|---|---|---|---|---|---|
| Thunderstorm Wind | 87 | 0 | $283K | 78 | 1975–2025 |
| Hail | 62 | 0 | $101K | 2.5 | 1961–2023 |
| Tornado | 33 | 1 | $353K | F3 | 1958–2017 |
| Flood | 20 | 0 | $2.2M | 0 | 2008–2021 |
| Flash Flood | 10 | 0 | $158K | 0 | 1997–2024 |
| Funnel Cloud | 9 | 0 | $0 | 0 | 1999–2018 |
| Lightning | 1 | 0 | $0 | 0 | 1996–1996 |
Decade by decade
Big Horn County, Wyoming severe weather history by decade
Reporting practice changed over time — early decades are undercounted, not calmer.
Tornado tracks
Paths crossing this county
31 mapped tornado paths intersect this county: 30 touched down inside it and 1 crossed in from a neighbouring county. This comes from path geometry, not county-tagged reports.
| Date | Scale | Deaths | Injuries | Path length | Origin |
|---|---|---|---|---|---|
| 1985-08-02 | EF3 | 0 | 0 | 0.2 mi | Touched down here |
| 1959-06-26 | EF2 | 1 | 1 | 9.2 mi | Touched down here |
| 1978-07-04 | EF2 | 0 | 1 | 5.0 mi | Touched down here |
| 1967-07-24 | EF2 | 0 | 0 | 0.1 mi | Touched down here |
| 1962-07-09 | EF2 | 0 | 0 | 0.5 mi | Touched down here |
| 1962-06-12 | EF2 | 0 | 0 | 0.5 mi | Touched down here |
| 1958-06-03 | EF2 | 0 | 0 | 0.2 mi | Touched down here |
| 2009-06-01 | EF1 | 0 | 0 | 0.4 mi | Touched down here |
| 2001-06-26 | EF1 | 0 | 0 | 0.7 mi | Touched down here |
| 1997-06-06 | EF1 | 0 | 0 | 1.0 mi | Touched down here |
Significant events
Deadliest events on record in Big Horn County
| Date | Type | Location | Deaths | Injuries | Damage |
|---|---|---|---|---|---|
| Jun 26, 1959 | Tornado | 1 | 1 | $3K | |
| Aug 7, 2009 | Hail | GREYBULL | 0 | 1 | $75K |
| Jul 4, 1978 | Tornado | 0 | 1 | $250K |
From the record
What the reports say
Written by National Weather Service staff at the time of the event · public domain
Medicine Lodge Creek rose rapidly during the early morning hours of Friday, June 24 as a result of snowmelt in the western Bighorn Mountains. The rising creek completely flooded the campground area and washed out portions of the main road at Medicine Lodge State Archaeological Site northeast of Hyattville. Water from the creek also ran down State Highway 31 which serves as Main Street in Hyattville. The basement of at least one home was inundated by flood waters from the creek. Officials dug a trench across the highway in Hyattville to relieve flood waters on the upstream side of the road. Flooding of agricultural land also occurred in areas between Hyattville and Manderson along the Nowood River and Medicine Lodge Creek.
Excessive snowmelt runoff caused flooding at Big Horn Lake. The lake elevation hovered about 15 feet above full pool at 3,655 feet. High water neared the level of the US Highway 14A causeway across the southern end of the lake. Wind gusts to 45 mph caused waves that eroded some of the embankment along the causeway and deposited debris onto the highway. On Friday night, July 22, the waves deposited enough debris to necessitate snowplows to come and clear the highway. County Road 20 along the west shore of the lake was inundated and sustained significant damage as a result of the prolonged period of high water.
Shell Creek and its tributaries caused flooding in and around the community of Shell. The flooding was a result of continued snowmelt in the western Bighorn Mountains as the warmest temperatures of the season were attained. Damage was reported on the Kedesh Guest Ranch and a county road along Trappers Creek.
Context
Risk, population and federal disasters
Very Low
FEMA NRI risk rating
11,828
Population (ACS)
$217K
Median home value
4
Federal declarations
| Declared | Incident | Title | Type |
|---|---|---|---|
| Apr 11, 2020 | Biological | COVID-19 PANDEMIC | DR |
| Mar 13, 2020 | Biological | COVID-19 | EM |
| Jul 22, 2011 | Severe Storm | SEVERE STORMS, FLOODING, AND LANDSLIDES | DR |
| May 29, 1978 | Flood | SEVERE STORMS, FLOODING & MUDSLIDES | DR |
Quick answers
Frequently asked
How many severe weather events have been recorded in Big Horn County, Wyoming?
222 events are on record between 1958 and 2025, causing 1 direct deaths and $3.1M in property damage.
What is the most common severe weather hazard in Big Horn County?
Thunderstorm Wind, with 87 recorded events — 39.2% of everything in the archive for this county.
How many tornadoes have crossed Big Horn County?
31 mapped tornado paths intersect the county boundary; 30 of them touched down inside it. This is derived from path geometry, not county-tagged reports.
How many federal disaster declarations cover Big Horn County?
4 federal disaster declarations from FEMA include Big Horn County, each tied to a specific incident period.
How risky is Big Horn County compared with the rest of the country?
FEMA's National Risk Index rates Big Horn County as very low risk, placing it in the 31 percentile of its state for expected annual loss.
Where does the Big Horn County, Wyoming severe weather history data come from?
Every figure is drawn from United States federal public-domain records: NOAA/NCEI Storm Events for the event archive, NOAA SPC SVRGIS for mapped tornado paths, FEMA for disaster declarations and risk ratings, and the U.S. Census for population context. Dates are shown in UTC and recent entries may still be revised by NOAA.
Nearby
Neighbouring counties
- Albany County 287
- Campbell County 1,114
- Carbon County 228
- Converse County 266
- Crook County 839
- Fremont County 452
Cite this page
“Big Horn County, Wyoming.” Severe Weather History. severeweatherhistory.com/county/wyoming/big-horn-county/ · Data: NOAA/NCEI, FEMA, U.S. Census — public domain.