Liberty County
Population 1,957 (2025) 1,430 sq mi
Liberty County has recorded 4 tornadoes since 1950, 30th most of 56 counties in Montana; the most recent was on June 2, 1999.
Hazard fingerprint Each spoke is this county’s percentile among U.S. counties where that hazard occurs. How it is computed
- Tornado damage paths since 19504
At a glance
The record for Liberty County in eight numbers. Each links to its section below.
Tornadoes since 1950
4
30th of 56 in Montana
Fewer than the typical Montana county, which has had 6
DetailsStrongest tornado
F1
May 25, 1980, 0.1 mile path
Snowiest season
81.0in
Winter of 2008-09
Tornadoes
About one every 19 years since 1950, none rated F3/EF3 or stronger.
Strongest
May 25, 1980
F1, 0.1 mile path
10 yards wide.
Most recent
Wednesday, June 2, 1999
F0, 0.1 mile path
27 years ago.
Every recorded tornado
| Jun 2, 1999 | F0 | 0.1 | 0 | 0 |
| Jun 27, 1996 | F0 | 0.2 | 0 | 0 |
| May 25, 1980 | F1 | 0.1 | 0 | 0 |
| May 24, 1977 | F1 | 0.1 | 0 | 0 |
- Injuries and deaths are for the tornado’s whole path, which may extend beyond the county. Deaths recorded within Liberty County: 0.
- 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.
Hurricanes and tropical storms
No tropical storm or hurricane has tracked within 100 miles since records began in 1851.
Wildfire and smoke
No large wildfire has been mapped here since satellite mapping began in 1984.
Smoke overhead
Smokiest year
2023: 54 days
Heavy smoke on 32 days in 2021, the most of any year.
Last 10 years
29.5 days a year
Medium or heavy smoke, 2016 to 2025.
2025
27 days
Medium or heavy smoke. 42 so far in 2026.
- 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.
Floods and flood insurance
4 federal flood insurance claims since 1996, with $7,075 paid.
Flood events since 1996
- Flood2
- Heavy Rain1
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.
Drought
In severe drought or worse for 136 of 1,581 months since 1895 (9%); the longest spell lasted 23 months.
136
Months in severe drought or worse since 1895
47
Months in extreme drought
9%
Share of all months, severe or worse
Lowest reading
August 1988
−6.00, extreme drought
Longest severe spell
23 months
June 2000 to April 2002.
Latest month
September 2026
+2.13, moderately wet
Last severe month: May 2005.
- 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.
Earthquakes
1 earthquake of magnitude 4 or more within 50 miles since 1900; the largest was magnitude 4.2 in 2026.
0
Magnitude 2.5+ inside the county since 1973
14
Magnitude 3+ within 50 miles since 1973
1
Magnitude 4+ within 50 miles since 1900
0
Magnitude 5+ within 50 miles since 1900
Largest within 50 miles
January 29, 2026
Magnitude 4.2
9 km N of Black Eagle, Montana; 36.7 miles away, 14.6 miles deep.
Most recent, magnitude 3 or more
September 18, 2026
Magnitude 3.7
7 km NNW of Black Eagle, Montana; 38.2 miles away.
Every earthquake of magnitude 4 or more within 50 miles
| Jan 29, 2026 | 4.2 | 36.7 |
- 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).
- 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.
Severe weather and other events
432 events in the National Weather Service record, 409 of them since 1996.
35
Hail reports, 1 inch or larger
4
Hail, 2 inches or larger
84
Damaging gusts, 58 mph+
35
Winter weather events since 1996
0
Heat events since 1996
21
Cold events since 1996
Largest hail
August 10, 1957
3.00 inches
Strongest measured or estimated gust
June 17, 2005
86 mph
More event types since 1996
| Lightning | 1 | 0 |
| Avalanches | 1 | 0 |
Costliest events since 1996
- Apr 7, 2023Flood$50,000
National Weather Service narrative
Roads north of Lothair become flooded from snowmelt. Liberty Co law enforcement closed several sections of several roads across the county.
- Aug 7, 1999Thunderstorm Wind$2,000
- Jun 8, 2000Hail$1,000
- Sep 1, 2004Thunderstorm Wind$1,000
National Weather Service narrative
A severe thunderstorm dropped .75 inch diameter hail and produced a wind gust to 60 mph at Chester 33N. The strong winds damaged several power poles, shearing them off 10 feet above the ground.
- 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.
Weather records
From Chester, 2.1 miles from the county’s population centre, with records from 1900.
- All-time high
- 105°FAug 5, 1961
- All-time low
- −57°FJan 25, 1950
- Warmest night
- 75°FMay 25, 1919
- Coldest day
- −32°FDec 29, 1968
- Wettest day
- 3.10 inJul 13, 1970
- Snowiest day
- 18.0 inOct 3, 2017
- Hottest year
- 1987mean 46.0°F
- Coldest year
- 1911mean 38.1°F
- Wettest year
- 201019.22 in
- Driest year
- 20004.65 in
- Snowiest season
- 81.0 in2008-09
Median first snow
November 9
Earliest: September 22, 1945
Median last snow
April 15
Latest: May 22, 2002
2 of 36 winters had no measurable snow.
Station Chester (USC00241692), 3,132 ft elevation, 2.1 miles from the population centre. Daily records from 1900 to October 26, 2026; 92.0% 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.
Federal disaster declarations
10 since 1953. The most recent: Covid-19 Pandemic, March 31, 2020.
| Mar 31, 2020 | Biological | DR-4508-MT |
| Mar 13, 2020 | Biological | EM-3476-MT |
| Aug 30, 2018 | Flood | DR-4388-MT |
| May 24, 2016 | Severe Storm | DR-4271-MT |
| Jun 17, 2011 | Severe Storm | DR-1996-MT |
| Sep 13, 2005 | Hurricane | EM-3253-MT |
| Jul 3, 2002 | Severe Storm | DR-1424-MT |
| Aug 30, 2000 | Fire | DR-1340-MT |
| May 16, 1996 | Severe Storm | DR-1113-MT |
| Mar 15, 1986 | Flood | DR-761-MT |
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.
How this compares
Where Liberty County stands among 56 counties in Montana and 3,143 in the United States.
| Tornadoes since 1950 | 4 | 30 / 56 |
| Tornadoes rated F3/EF3 or stronger | 0 | — |
| Tropical cyclones within 50 mi | 0 | — |
| Hurricane-strength passes within 50 mi | 0 | — |
| Wildfire acres since 1984 | 0 | — |
| Flood insurance claims | 4 | 41 / 56 |
| Flood insurance paid | $7,075 | 40 / 56 |
| Disaster declarations | 10 | 27 / 56 |
| Flood events since 1996 | 3 | 56 / 56 |
| Hail and wind events since 1996 | 347 | 31 / 56 |
| Winter storm events since 1996 | 35 | 56 / 56 |
| Reported damage since 1996 | $54,000 | 51 / 56 |
| River crests at major flood stage | 0 | — |
| High tide flooding days a year, last 10 years | 0.0 | — |
| Months in severe drought since 1895 | 136 | 33 / 56 |
| Medium or heavy smoke days a year, last 10 years | 29.5 | 24 / 56 |
| Earthquakes M4+ within 50 mi since 1900 | 1 | 37 / 56 |
| Earthquakes M2.5+ in the county since 1973 | 0 | — |
Neighbouring counties
| Chouteau County | 17 | 0 |
| Hill County | 7 | 0 |
| Pondera County | 0 | 0 |
| Toole County | 7 | 0 |
Sources and vintage
Every number on this page comes from these public records.
- 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 USC00241692.
- 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.