O'Brien County

Every recorded tornado

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

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.

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.

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.

Costliest events since 1996

1. Apr 9, 2013Winter Storm, O'Brien$10.0 million
   National Weather Service narrative

   An extended period of precipitation began with freezing rain quickly producing heavy ice accumulations, ranging up to between a quarter and half inch. The precipitation then changed to sleet and then snow, with sleet and snow accumulations reaching 3 to 6 inches. Many branches, limbs, whole trees, and power lines were downed by the weight of ice and accompanying wind, especially over the northern part of the county. Both urban areas and rural electric cooperatives suffered major power line damage. Trees and tree debris blocked many roads, and damaged several vehicles and homes. Major power outages were reported, affecting thousands of people. The winter precipitation made travel…

2. Jun 21, 2024Flood$2.3 million
   National Weather Service narrative

   Rainfall amounts across O'Brien County from June 20-22 ranged from 5 to 9 inches, with the highest amounts across the northern half of the county. Widespread overland flooding ensued with additional minor to major flooding along the Floyd and Little Floyd Rivers, and Waterman Creek. ||County-wide, there were five water rescues during peak flooding, involving 18 individuals. An estimated 700 to 1,000 homes were impacted by flood waters with a majority of the residential property damage reported in Hartley and Sheldon. Some homes became islands and required residents to shelter in place until the water receded, while at least two homes needed to be evacuated. An apartment complex in…

3. Jul 9, 2009Hail$2.0 million
   National Weather Service narrative

   Large hail caused widespread damage in and near Sheldon. The hail broke windows on vehicles and buildings, including 35 out of the 37 skylights on the local high school. The hail also severely dented vehicles, roofs, and siding, and caused tree damage. The hail also damaged crops near the city, but the amount of crop damage was not known.

4. Jun 22, 2015Thunderstorm Wind$1.0 million
   National Weather Service narrative

   Thunderstorm winds destroyed an airport hangar, and destroyed or damaged 5 planes in the hangar. The winds caused widespread tree damage, including numerous trees blown down or completely uprooted. The tree damage included many trees at a local golf course. The winds damaged homes and buildings in and near Sheldon, including one home that was damaged by a large falling tree. A large silo was damaged and several small farm buildings were destroyed. The farm damage included a large shed destroyed and machinery inside the shed damaged. A commercial building under construction was destroyed.

5. Mar 13, 2019Flood$590,000
   National Weather Service narrative

   Flooding resulted in extensive damage to public infrastructure including numerous county and township roads, culverts, and some bridges.

6. Sep 17, 2021Thunderstorm Wind$350,000
   National Weather Service narrative

   A roof was completely torn off the end of a strip mall and deposited in pieces on the roadway. Property damage costs are a rough estimate.

7. Oct 16, 1996Thunderstorm Wind$300,000
   National Weather Service narrative

   Thunderstorm winds destroyed a school bus garage, damaged school busses and a school, ripped the roof off of a bowling alley, blew down large trees, and broke house and vehicle windows.

8. Jun 11, 2008Tornado$200,000
   National Weather Service narrative

   A tornado destroyed several outbuildings, moved a 1.5 ton wagon, heavily damaged a machine shed containing farm equipment and also damaged a nearby house on the same farm. Also destroyed another machine shed at a different location, destroyed a pole barn, damaged a grain bin, broke or blew down several power poles and power lines, and caused tree damage.

9. Jun 13, 2001Tornado$200,000
   National Weather Service narrative

   A tornado downed trees in Calumet and Sutherland, some of which caused severe damage to homes. The tornado also blew chimneys off at least two houses, caused other tree damage, knocked down power lines, and destroyed the concession stand at a softball field.

10. Jun 13, 2001Thunderstorm Wind$150,000
    National Weather Service narrative

    Thunderstorm winds caused tree damage, with a large tree limb falling on a garage.

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

110°FJul 17, 1936

All-time low

−35°FFeb 2, 1917

Warmest night

80°F2 times, most recently Aug 4, 1982

Coldest day

−15°FDec 23, 1983

Wettest day

6.62 inJul 22, 2010

Snowiest day

15.0 inDec 28, 1982

Hottest year

1931mean 51.1°F

Coldest year

1996mean 41.6°F

Wettest year

201854.39 in

Driest year

192513.77 in

Snowiest season

76.5 in1935-36

Station Sanborn (USC00137386), 1,527 ft elevation, 4.0 miles from the population centre. Daily records from 1914 to October 26, 2026; 99.5% 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 USC00137386.
• 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.