Sanders County

Every recorded tornado

1. Injuries and deaths are for the tornado’s whole path, which may extend beyond the county. Deaths recorded within Sanders 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.

More event types since 1996

Costliest events since 1996

1. Feb 8, 2018Winter Storm, Flathead/Mission Valleys$5.0 million
   National Weather Service narrative

   Severe driving conditions occurred in the Flathead and Mission valleys the evening of the 8th through the morning of the 9th due to snow and blowing snow. A peak wind gust of 56 mph occurred at Glacier Park International Airport at 4:46 pm on the 8th during the evening commute with minor power outages also noted.

2. Aug 1, 2021Wildfire, Flathead/Mission Valleys$3.6 million
   National Weather Service narrative

   The Boulder 2700 fire spread quickly during the early morning hours of August 1st in the presence of strong downslope winds and dry conditions. The fire ran down the west slope of the Mission Mountains, crossing Montana Highway 35, reaching the east shore of Flathead Lake. Damage surveys confirmed the loss of 14 primary structures and 17 outbuildings.

3. Dec 17, 2025High Wind, Flathead/Mission Valleys$1.0 million
   National Weather Service narrative

   A historic high wind event impacted the Flathead and Mission Valleys on December 17, 2025, as a powerful cold front brought high winds acting on soils super-saturated by a preceding atmospheric river. Peak gusts frequently exceeded 60 mph across the valley floors, including 67 mph at 0855MST at Glacier Park International Airport, 64 mph at 0915MST at Elmo, and 62 mph at 0900MST at the Creston Agrimet station. The Flathead County Sheriff's Office issued a travel advisory at 1000MST due to hazardous conditions and widespread disruptions. Significant transportation impacts included the closure of US-93 near Somers after a semi-truck was blown across the roadway, and multiple lane…

4. Apr 11, 2020Strong Wind, Flathead/Mission Valleys$1.0 million
   National Weather Service narrative

   Gusty north and east winds were felt across the Flathead Valley and Flathead Lake with gusts over 40 mph being observed. A downed tree damaged power lines on Echo Lake Road northeast of Bigfork. Flathead Electric noted 400 customers lost power during this strong northeast wind event.

5. May 1, 1997Flood, Flathead/Mission Valleys$912,000
   National Weather Service narrative

   Snowmelt flooding caused numerous road closures and road washouts throughout the region. In Flathead County, at least three road washouts were reported and one bridge damaged. At least 50 homes were flooded, mainly along Ashley Creek and the Stillwater, Swan and Whitefish Rivers. 50 people were isolated along Truman Creek, which washed out an access road. In Missoula County, at least four bridges were damaged, including a collapsed bridge on Sun Ray Lane in Lolo. Hardest hit was property along the Clark Fork River, Lolo and Rock Creeks. Several culverts and dikes were damaged. In Sanders County, extensive flooding occurred from Plains to Thompson Falls. One road washout resulted…

6. Feb 7, 1996Flood, Lower Clark Fork Region$700,000
   National Weather Service narrative

   Warmer temperatures, after an extended cold and snowy period, caused numerous flooding problems across central Montana during the second week of February. Snowmelt over frozen ground caused streams and rivers to go out of their banks, washing out roads and bridges. Flooding problems ranged from minor inundation of fields to portions of towns being under water. Ice jams also caused flooding problems as snowmelt ran into frozen streams and rivers. Some of the worst flooding occurred in East Helena where 3 creeks went out of their banks, damaging over 150 homes. Ice jams on the Missouri river caused flooding in Fort Benton. Much of the town was under 1 to 2 feet of water at one…

7. Jun 2, 2005Flood, Flathead/Mission Valleys$700,000
   National Weather Service narrative

   Three days of moderate to heavy rain on top of snow pack in the Mission and Swan Mountains caused small creeks to flood with mud and debris flows causing damage. Total rainfall amounts ranged from 2.50 inches in the valleys, and 4 to 7 inches over higher terrain in Lake County. Damage occurred mainly in Lake County due to washouts of roads and clogged culverts from debris and water flowing out of the Mission Mountains. Several bridges along creeks were also damaged. The worse damage occurred along the east side of Flathead Lake on Highway 35 between mile markers 9 and 12. The highway was closed for several days from several creeks that had washed out and covered the highway with…

8. Dec 17, 2025High Wind, Kootenai/Cabinet Region$610,000
   National Weather Service narrative

   At 0940 MST, the Lincoln County Sheriff���s Office issued an Emergency Travel Only order as downed trees and power lines rendered major routes���including US-2 and MT-56���impassable. In Libby, a failure of the cellular network created a communications gap for emergency services during the peak of the event.||Property damage was widespread; numerous homes and structures were struck by falling timber, including a home 4 miles NW of Troy and a garage up Pipe Creek. Private losses were notable, including multiple totaled greenhouses and several vehicles crushed by falling Ponderosa pines, such as a late-model truck near the Libby airport and another at Bull Lake.…

9. May 1, 1997Flood, Kootenai/Cabinet Region$543,000
   National Weather Service narrative

   Snowmelt flooding caused numerous road closures and road washouts throughout the region. In Flathead County, at least three road washouts were reported and one bridge damaged. At least 50 homes were flooded, mainly along Ashley Creek and the Stillwater, Swan and Whitefish Rivers. 50 people were isolated along Truman Creek, which washed out an access road. In Missoula County, at least four bridges were damaged, including a collapsed bridge on Sun Ray Lane in Lolo. Hardest hit was property along the Clark Fork River, Lolo and Rock Creeks. Several culverts and dikes were damaged. In Sanders County, extensive flooding occurred from Plains to Thompson Falls. One road washout resulted…

10. Jan 13, 2021High Wind, Kootenai/Cabinet Region$500,000
    National Weather Service narrative

    This was a very widespread wind event for northwest Montana. Countless trees were either blown down or snapped in half in many locations, causing numerous road blockages. At least 2 dozen trees were blown over along Bull Lake Road, 10 miles north of Heron. One power company reported that they had 51 broken power poles, and experienced extensive power line and cross arm damage during the event. Winds were gusting up to 80 mph at the Zonolite station which is situated 2,000 feet above the Libby area. Wind gusts between 66 and 70 mph were reported in the valleys in the Idaho Panhandle and based on the fact that trees were down all over Lincoln County, these wind speeds are a good…

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

107°F2 times, most recently Aug 11, 2018

All-time low

−25°FDec 30, 1968

Warmest night

73°FJul 24, 2007

Coldest day

−5°F3 times, most recently Jan 13, 2024

Wettest day

2.23 inJun 8, 1964

Snowiest day

14.0 inDec 17, 1961

Hottest year

2015mean 51.7°F

Coldest year

2014mean 45.7°F

Wettest year

199632.54 in

Driest year

202314.50 in

Snowiest season

99.6 in1977-78

Station Thompson Falls Ph (USC00248211), 2,380 ft elevation, 9.0 miles from the population centre. Daily records from 1956 to October 26, 2026; 96.3% 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 USC00248211.
• 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.
• 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.