Gallatin County

Every recorded tornado

1. Injuries and deaths are for the tornado’s whole path, which may extend beyond the county. Deaths recorded within Gallatin County: 0.
2. Weak tornadoes were under-recorded before Doppler radar coverage became national in the early 1990s, so earlier decades read low. Ratings use the Fujita scale before February 2007 and the Enhanced Fujita scale after.

Storm Prediction Center severe weather database, 1950 to 2025.

Every large fire

1. Large fires mapped by the Monitoring Trends in Burn Severity program since 1984: 1,000 acres or more in the West, 500 or more in the East. Prescribed burns are excluded. Acres here are the part of each perimeter inside this place.

Monitoring Trends in Burn Severity (USGS and U.S. Forest Service), 1984 to 2026.

Smoke overhead

1. A smoke day is a date on which a smoke plume traced by NOAA Hazard Mapping System analysts from satellite imagery covered this place's point (the county's population centre or the city centre). Counts here are of medium or heavy smoke. Since 2018 analysts have often drawn light smoke as one area over most of the continent, so light-smoke counts are not comparable from year to year. The plumes show smoke anywhere in the air above, not air quality at the ground, and smoke hidden by cloud is missed.

NOAA Hazard Mapping System smoke analysis, 2011 to 2026, retrieved October 30, 2026.

Claims by ZIP code

This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).

OpenFEMA NFIP Redacted Claims v3, refreshed August 4, 2026. NOAA Storm Events through 2026.

River crests

River gauges

1. Crests are the highest and the recent crests the National Weather Service lists for each river gauge in the county that has a flood stage, not every flood. Flood categories use each gauge's current flood stages; crests from before levees, dams or channel changes may not be comparable. Crests measured on an old datum are left out of the rankings.

NOAA National Water Prediction Service gauge records, retrieved October 30, 2026.

1. The Palmer Drought Severity Index is computed by NOAA each month from the county's average temperature and precipitation, relative to the county's own climate. Zero is normal; -3 or lower is severe drought and -4 or lower extreme drought. It describes the long-term balance of moisture, not water supply or crop losses.

NOAA NCEI nClimDiv county Palmer Drought Severity Index, 1895 to September 2026, issued October 6, 2026.

Every earthquake of magnitude 4 or more within 50 miles

1. Earthquakes of magnitude 2.5 or more in the USGS Comprehensive Catalog since 1900. Within 50 miles means the epicentre lies within 50 miles of the county boundary (or inside the county).
2. Small earthquakes were under-recorded before the modern seismic networks of the 1970s and are still missed in remote areas, so early decades read low. Magnitudes are as the catalogue reports them and mix scales (moment, local and body-wave).

USGS ANSS Comprehensive Earthquake Catalog, 1900 to present, retrieved October 30, 2026.

Volcanoes within 100 miles

1. U.S. volcanoes within 100 miles, from the USGS Volcano Hazards Program. The threat category is the USGS 2018 National Volcanic Threat Assessment, which ranks volcanoes by how hazardous their past eruptions were and how many people and how much infrastructure lie near them. It is not a forecast of eruption.

USGS Volcano Hazards Program, retrieved October 30, 2026.

Mapped landslides

Mapped by USGS Conterminous (9).

1. Landslides mapped in the USGS compilation of landslide inventories across the United States (version 3.0, 2025), rated probable or better. The compilation joins inventories made by federal and state agencies for different purposes and areas, so the number mapped in a county reflects how closely it has been surveyed as much as how often its slopes fail. An area with few records may simply not have been mapped. Deaths are as recorded in the inventories; a slide listed in two inventories is counted once.

USGS Landslide Inventories across the United States, version 3.0, retrieved October 27, 2026.

More event types since 1996

Costliest events since 1996

1. Jun 30, 2010Hail$60.0 million
   National Weather Service narrative

   A thunderstorm dropped 1 inch diameter hail at Bozeman.

2. Apr 10, 2023Flood$1.0 million
   National Weather Service narrative

   Churchill area saw pretty good runoff occur. Several locations around Amsterdam (Camp and Godfrey Creeks) had water up against houses. The Highline Canal near Gallatin Gateway overtopped in several locations due to runoff. One house and Axtell Anceny Road were affected. Residents on Dry Creek Road and Swamp Creek Road had flood water around houses. This caused the evacuation of the Bootstrap Ranch. County Roads had several roads closed with water on them.

3. Oct 15, 1998Winter Storm, Yellowstone National Park Mt Id / W Park / N Teton$1.0 million
   National Weather Service narrative

   A severe winter storm moved across Western and Central Wyoming dumping locally heavy snow from southern Yellowstone National Park to the Casper area. The main brunt of the storm was felt in the Casper area where up to 17 inches of snow fell. Strong winds accompanied the heavy snow causing widespread tree damage and power outages. Poor visibilities and icy road conditions caused numerous vehicle accidents.

4. Mar 12, 2003Flood, Gallatin$500,000
   National Weather Service narrative

   With a major snowstorm falling in the mountains in the Helena Valley on March 6th through the 10th, and temperatures quickly rising to near 70 degrees by the 12th, a rapid snow melt occurred in the mountains. This snow melt quickly filled all small streams and creeks. As the snow continued to melt during the afternoon hours, the creeks began to overflow, as some culverts were blocked with ice and debris. The result was some nearby homes and roads next to the creeks were either damaged or washed out. Water was up to a foot deep in some locations. Damage reports in the Helena Valley included about 20 homes with flood damage, and a few secondary roads washed out. The damage cost was…

5. Jun 13, 2001Heavy Snow, Gallatin$354,000
   National Weather Service narrative

   14 inches snowfall reported by spotter at the Montana State University campus in Bozeman...Numerous tree limbs and power lines were downed across town by the weight of the wet snow (automobile damage also occurred due to the falling tree limbs)...damage cost estimate based upon report in newspaper stating that a total of $354000 in damage was done by snow storm to the Bozeman area (including the city of Bozeman...Montana State University...Bozeman Public Schools...and Park Electric Cooperative).

6. Jul 18, 2004Debris Flow, Yellowstone National Park$275,000
   National Weather Service narrative

   A thunderstorm produced very heavy rain late in the evening over Sylvan Pass. A slide of mud and earth oozed onto U.S. Highway 16 about 6 miles west of Yellowstone National Park's east entrance. Four feet of mud and debris trapped sixteen people in four vehicles for three hours. The debris flow was estimated to contain 30,000 tons of mud and rock and was in some cases 10 feet deep. The east entrance of Yellowstone National Park was closed for four days following the mudslide. No injuries occurred.

7. Sep 1, 2000Wildfire$160,000
   National Weather Service narrative

   Maudlow/Toston fire - included Broadwater County, 81687 acres burned, 1 resident destroyed, 1 outbuilding destroyed, human caused, continued from August.

8. Aug 15, 2000Wildfire$160,000
   National Weather Service narrative

   Maudlow/Toston fire - included southeast Broadwater County, 81687 acres burned, 1 resident destroyed, 1 outbuilding destroyed, human caused, continued past August 31.

9. Mar 14, 2023Winter Storm, Gallatin And Madison County Mountains And Centennial Mountains$150,000
   National Weather Service narrative

   Numerous traffic wrecks across the area due to winter weather conditions. US 191 between Big Sky and Gallatin Gateway was completely shutdown at times due to accidents. 16 accidents occurred in the Big Sky area due to weather. One included six vehicles and one semi. No injuries were reported. SNOTEL sites received snow amounts ranging from 8 to 10 inches.

10. Aug 5, 1996High Wind, Yellowstone National Park$54,000

1. Storm Events records before 1996 cover only tornadoes, thunderstorm wind and hail. Damage figures are as reported by the National Weather Service at the time, not adjusted for inflation.

NOAA NCEI Storm Events Database, 1950 to 2026, issued October 26, 2026.

All-time high

106°F2 times, most recently Jul 12, 2026

All-time low

−46°F2 times, most recently Dec 24, 1983

Warmest night

67°FAug 26, 1970

Coldest day

−24°FDec 22, 2022

Wettest day

2.14 inJun 25, 1969

Snowiest day

11.0 inDec 23, 1955

Hottest year

2007mean 47.0°F

Coldest year

1975mean 38.9°F

Wettest year

196920.04 in

Driest year

19618.65 in

Snowiest season

76.0 in1948-49

Station Bozeman Gallatin Field Airport (USW00024132), 4,431 ft elevation, 7.4 miles from the population centre. Daily records from 1941 to October 26, 2026; 96.5% of days in the last 30 years are complete. Records at a single station can differ from a city’s official threaded record, which may combine several stations.

NOAA NCEI Global Historical Climatology Network Daily.

This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).

OpenFEMA Disaster Declarations Summaries, retrieved October 30, 2026. Statewide declarations are not listed.

Neighbouring counties

• Tornadoes NOAA Storm Prediction Center severe weather database, through 2025.
• Tropical cyclones NOAA National Hurricane Center HURDAT2 (Atlantic; Northeast and Central Pacific), through 2025.
• Wildfire USGS/USFS Monitoring Trends in Burn Severity, through 2026.
• Storm events NOAA NCEI Storm Events Database, through 2026.
• Flood insurance OpenFEMA NFIP Redacted Claims v3, refreshed August 4, 2026.
• Declarations OpenFEMA Disaster Declarations Summaries v2, retrieved October 30, 2026.
• Weather records NOAA NCEI Global Historical Climatology Network Daily, station USW00024132.
• River crests NOAA National Weather Service, National Water Prediction Service river gauges, retrieved October 30, 2026.
• Drought NOAA NCEI nClimDiv county Palmer Drought Severity Index, through September 2026.
• Smoke NOAA NESDIS Hazard Mapping System smoke analysis, retrieved October 30, 2026.
• Volcanoes USGS Volcano Hazards Program, U.S. volcanoes and 2018 threat assessment.
• Landslides USGS Landslide Inventories across the United States, version 3.0 (2025).
• Earthquakes USGS ANSS Comprehensive Earthquake Catalog (ComCat), retrieved October 30, 2026.

Joins, thresholds and known limits are set out in the methodology. Found an error? Report it. Page built October 30, 2026.