Winnebago County

Every recorded tornado

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

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.

More event types since 1996

Costliest events since 1996

1. Aug 1, 2003Drought, Winnebago$12.7 million
   National Weather Service narrative

   Dry weather settled in over Iowa during the month. The last widespread rain occurred on 09 July. With the increasingly dry conditions became a primary concern as the month progressed. An extended period of heat and humidity from the 15th to 25th saw highs into the 90s to over 100 degrees F. in some locations. By month's end drought indices had worsened to severe to extreme drought across south central Iowa and at least moderate drought over the remainder of the HSA. Waterloo had its driest August on record, Des Moines its 3rd driest and Ottumwa its 8th driest. A cold front brought only a brief respite from the intense heat, as temperatures rebounded into the 90s to near 100…

2. Jun 22, 1997Hail$1.5 million
3. Nov 10, 1998High Wind, Winnebago$300,000
   National Weather Service narrative

   Iowa experienced the worst November storm system since the great storm of 9 and 10 November 1975. During the 9th, low pressure developed over southeast Colorado. The low moved across Kansas during the afternoon and evening of the 9th and deepened to about 990 mb. Warm and moist air was drawn north ahead of the low resulting in widespread across the state. Thunderstorms erupted during the late evening of the 9th, though no severe weather occurred. During the predawn hours of the 10th, a jet streak rotated around the base of the upper level low pressure area. The jet stream, combined with a tropospheric fold, resulted in explosive deepening of the low. As the low moved through…

4. Jun 7, 2008Tornado$250,000
   National Weather Service narrative

   Rain wrapped tornado. Tornado hit hog confinement building and destroyed it. A barn was also damaged.

5. Feb 24, 2007Winter Storm, Winnebago$250,000
   National Weather Service narrative

   A major winter storm affected Iowa through the 24th and 25th of February. A powerful upper low moved onto the west coast during the middle of the week, and advanced east through the Rockies during the end of the week. Strong warm air advection took place over the top of a shallow polar airmass that was in place over Iowa. The east-southeasterly flow at the surface drew cool and dry air into the state from the east, setting the stage for a significant ice storm. The main area of precipitation overspread the state during the early morning hours of the 24th and persisted through much of the 25th. Initially, very warm air aloft meant that the precipitation fell in the form of freezing…

6. May 16, 1999Flood, Winnebago$200,000
   National Weather Service narrative

   May of 1999 saw several significant flooding episodes across the Des Moines CWA. For the most part, central Iowa was spared the extremely heavy rainfall that caused major, and at several locations record, flooding along rivers in the northeast and east parts of the state. The most serious flooding was caused by heavy rains during the overnight hours of May 16. The heaviest rains fell in the counties just to the northeast of the Des Moines CWA. Up to 8 inches of rain fell over parts of Fayette County with anywhere from 2 to 6 inches falling over parts of Butler, Bremer, and Black Hawk Counties. Most of the rain fell in the Cedar River basin, which includes the West Fork Cedar…

7. Jun 26, 2010Thunderstorm Wind$200,000
   National Weather Service narrative

   Law enforcement reported a farmstead with 4 grain bins destroyed. Roof missing off shed and half of the structure destroyed.

8. Jun 27, 1998Thunderstorm Wind$150,000
   National Weather Service narrative

   Iowa was located in the warm sector of a developing storm system to the west. The warm front had moved to the northern Iowa border during the afternoon of the 27th with dew point temperatures in the mid 70s to around 80 blanketing the state in the warm sector. Initially, the airmass was capped, preventing thunderstorms from forming during the afternoon. Slightly cooler air moved in during the evening hours. In addition to the slightly cooler air moving in aloft, a cold front was poised over eastern Nebraska ready to move east into the state. Thunderstorms erupted rapidly by early evening with hail and high winds reported over northern Iowa. There were numerous reports of hail of…

9. Jun 20, 1998Flash Flood$150,000
   National Weather Service narrative

   A cold front to the west of Iowa moved into the state during the day. Initially, the airmass was quite capped and thunderstorms had a hard time getting going. Thunderstorms formed on the north edge of the cap over Minnesota, with the tail end of the storms reaching into north central Iowa. There was very little severe weather associated with the storms in Iowa. Heavy rain was the major concern as the ground was already saturated over a large part of the state. Heavy rain of 3 to 5 inches fell over north central Iowa. Five inches of rain was recorded in Scarville, in Winnebago County. Flash flooding was reported around the county with several roads flooded. The line of…

10. Sep 10, 2000Lightning$150,000
    National Weather Service narrative

    An unstable airmass was in place over Iowa with high temperatures reaching the mid 80s and 90s across the state combined with dew point temperatures in the 70s. A cold frontal system slipped southeast into the state during the late afternoon and evening hours of the 10th. A line of thunderstorms developed ahead of the front, however the push of the cold front stopped by around midnight. Thunderstorms dropped hail up to an inch in diameter over north central Iowa. The hail reportedly covered the ground northeast of Manly in Worth County. Thunderstorms continue in the area after the severe weather passed. One thunderstorm moved over Winnebago County around midnight. Lightning struck…

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°FJul 14, 1936

All-time low

−36°FJan 12, 1912

Warmest night

79°F3 times, most recently Jun 11, 1954

Coldest day

−20°FJan 11, 1912

Wettest day

7.51 inAug 31, 1962

Snowiest day

20.0 inMar 19, 1933

Hottest year

1931mean 50.6°F

Coldest year

1951mean 41.8°F

Wettest year

193846.76 in

Driest year

191016.27 in

Snowiest season

86.0 in2017-18

Station Forest City 2 Nne (USC00132977), 1,280 ft elevation, 4.3 miles from the population centre. Daily records from 1894 to July 3, 2026; 86.4% 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 USC00132977.
• 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.