Woodbury County

Every recorded tornado

1. Injuries and deaths are for the tornado’s whole path, which may extend beyond the county. Deaths recorded within Woodbury County: 2.
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.

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.

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.

Mapped landslides

Mapped by NASA (2).

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. Jul 2, 1999Flash Flood$8.0 million
   National Weather Service narrative

   A flash flood was caused by 3 or more inches of rain in less than an hour. Many basements were flooded and left with mud and debris. Some foundations and basement walls collapsed, mainly in Sioux City. Many roads were flooded, at one intersection to a depth of eight feet, damaging vehicles by the water and debris. The flooding brought down some trees, and damaged some of the flooded streets as water undercut them. A motorist caught in the flooding and the firefighter who rescued him were treated at a hospital for hypothermia. The flooding caused crop damage in the countryside, but the amount of crop damage was not determined.

2. Mar 13, 2019Flood$6.8 million
   National Weather Service narrative

   Water inundated western areas of Moville during the evening of March 13, and continued through early on March 15. Iowa Highway 140 was closed north of Highway 20 at Moville due to flooding. At the height of the flooding, 29 sections of roadway were closed in Woodbury County, including two sections requiring long term repairs (Highway 982 near Holly Springs and County road L37 near Danbury). Other flooding resulted in extensive damage to public infrastructure. Gravel roads were hit especially hard as ice-plugged culverts resulted in large sections of roadway washing away.

3. Jul 20, 2008Thunderstorm Wind$5.0 million
   National Weather Service narrative

   Thunderstorm winds caused widespread damage in and near Sioux City. Tree damage included large trees blown down, blocking several roads. A few vehicles were destroyed and numerous vehicles damaged by falling trees and tree debris. Falling trees also damaged several residences and garages, causing one known injury. The winds lifted a three car garage off its foundation, and overturned it onto a nearby pasture. One large tree split an occupied trailer in the middle, missing residents who were sleeping at both ends. Numerous power lines and poles were blown down or broken, leaving an estimated 19,000 customers without power, several thousand of which were still without power 24 hours…

4. Aug 2, 2001Thunderstorm Wind$5.0 million
   National Weather Service narrative

   Downburst thunderstorm winds caused extensive tree damage in Sioux City. Large trees were uprooted, snapped, and stripped. A few vehicles were completely destroyed by the falling trees. Houses and other buildings, including a nursing home, were also damaged by trees and debris. Many streets were blocked. Power lines and poles were also blown down, resulting in power outages affecting at least forty thousand people. Traffic lights were blown down. Roofs were damaged, including the roof blown off a medical office building, and sheet metal ducting blown off a roof. A 95 foot radio tower was also blown down, damaging a car and small building.

5. Jun 22, 2024Flood$4.1 million
   National Weather Service narrative

   Rainfall amounts across Woodbury County from June 20-22 were generally 1.0 inch or less. Farther north and upstream, 6 to 10 inches fell across portions of northwest Iowa and southeast South Dakota. This rainfall resulted in record flooding along the Big Sioux, Little Sioux, and Floyd Rivers, and extensive overland flooding along the adjoining flood plains. ||Multiple communities were impacted by flood waters. At peak flooding, numerous swift water rescues were conducted. Approximately 1,000 people were evacuated from the Riverside Neighborhood of Sioux City, 500 people were evacuated from Correctionville, and 10 people were evacuated from Smithland. County-wide, there were…

6. Oct 4, 2013Tornado$2.0 million
   National Weather Service narrative

   A tornado severely damaged or destroyed about 10 houses, collapsing most walls on a few of the houses, tearing most of the roofs off other houses, and shifting what was left of some houses off their foundations. The tornado caused significant damage to roofs, windows, and siding of additional houses. Numerous farm outbuildings, storage buildings, and a few silos were destroyed or severely damaged. The tornado also destroyed or damaged several pieces of farm equipment, caused significant tree damage, including numerous trunks snapped or uprooted and other trees stripped, and blew down power poles and lines. The tornado then crossed into Cherokee County.

7. May 28, 1998Hail$1.4 million
   National Weather Service narrative

   Widespread hail caused extensive damage to windows and crops, with other home damage also occurring.

8. Jun 17, 2014Flood$1.0 million
   National Weather Service narrative

   Persistent heavy rains caused major flooding of the Little Sioux River. Much farmland, other lowlands, and roads near the river were flooded. The flooded roads included several in and near Correctionville. A trail bridge was washed out near Oto. Several homes and businesses were flooded, especially in basements. The river crested at 5.45 feet above flood stage at Correctionville on June 20th.

9. Jul 16, 1996Flash Flood$1.0 million
   National Weather Service narrative

   Heavy rainfall of 6 to 11.5 inches caused flash flooding of roads including urban areas, as well as creeks and lowlands. Several levee failures were reported along Wolf Creek. Basement flooding and some flooding of ground level floors occurred.

10. May 28, 1998Hail$500,000
    National Weather Service narrative

    Widespread hail caused extensive damage to windows and crops, with other home damage also occurring.

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

108°F2 times, most recently Jul 12, 1995

All-time low

−28°F3 times, most recently Feb 16, 2021

Warmest night

81°FJun 21, 2025

Coldest day

−13°FDec 21, 1989

Wettest day

5.50 inJul 17, 1972

Snowiest day

18.4 inMar 15, 2004

Hottest year

2012mean 52.5°F

Coldest year

1996mean 45.1°F

Wettest year

201441.36 in

Driest year

197614.33 in

Snowiest season

65.9 in1961-62

Station Sioux City Airport (USW00014943), 1,092 ft elevation, 6.6 miles from the population centre. Daily records from 1940 to October 26, 2026; 100.0% 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.

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 USW00014943.
• 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.
• 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.