Wisconsin floods
Every recorded flood since 1996 · 72 counties with a record
NOAA's Storm Events Database records 2,580 floods and flash floods in Wisconsin from 1996 through June 30, 2026, about 87 a year since 2000. The deadliest was the July 11, 2016 flash flood in Iron County: 3 deaths, 2 injuries and $1,230 in damage in 2025 dollars across 4 records. Wisconsin ranks 29th of 52 states and territories by count and 34th of 51 per square mile.
Floods in Wisconsin, 1996 to 2026
Flood records per year (NOAA Storm Events); 2026 to June 30, 2026.
- recorded, no damage figure
- under $1 million
- $1 million or more
- $10 million or more
- $100 million or more, or 10 deaths
- $1 billion or more, or 100 deaths
- a year's colour: its recorded damage or deaths
- a year with a death
- Records
- 2,5801996 to June 30, 2026
- A year since 2000
- 87average
- Deaths
- 3030 injuries
- Damage, 2025 dollars
- $3.3Bas filed
- Busiest year
- 2018245 records
Source: NOAA NCEI Storm Events Database, records through June 30, 2026; deaths and damage as filed, damage in 2025 dollars. Search the record at NCEI.
Are floods and flash floods common in Wisconsin?
Wisconsin averages about 87 floods and flash floods a year since 2000, 29th of 52 states and territories by count. The busiest year on record was 2018 (245). Per 10,000 square miles of land, Wisconsin records 476 floods and flash floods since 1996, 34th of 51 states and territories by that measure.
Source: NOAA NCEI Storm Events Database, records since 1996, per 10,000 square miles of land area (Census Bureau 2024 Gazetteer; places under 1,000 square miles not ranked). Damage colours: Storm Events damage, 2025 dollars.
Which counties in Wisconsin have the most floods and flash floods?
Per square mile, Milwaukee County leads Wisconsin: 67 days with a flood since 1996, 277.5 per 1,000 square miles of land. By raw count, Vernon County has the most flood records (155 since 1996); large counties collect more records simply by covering more ground, so the ranking counts days with a record per unit of area (a storm filed for several forecast zones adds several records but one day).
Source: NOAA NCEI Storm Events Database, days with a record in the county since 1996 per 1,000 square miles of land (Census Bureau 2024 Gazetteer); in brackets, the count of records.
When is flood season in Wisconsin?
40% of its floods and flash floods since 1996 fell in June and July. The busiest month is June (635 records).
The values, month by month
Jan 17 · Feb 67 · Mar 157 · Apr 277 · May 221 · Jun 635 · Jul 403 · Aug 382 · Sep 280 · Oct 111 · Nov 8 · Dec 22 (records).
Source: NOAA NCEI Storm Events Database, records by the month they began, since 1996.
What were the deadliest floods and flash floods in Wisconsin?
| Date | Record | Character | Killed | Injured | Damage |
|---|---|---|---|---|---|
| 2016-07-11 | Flash FloodCedar, Iron County One storm episode: 4 records in 3 places, 2016-07-11 to 2016-07-14; the totals are the episode's. Thunderstorms brought heavy rain to northwest Wisconsin early Monday, July 11th which helped to saturate the soil. During the day a strong low level jet pumped very moist air into the region. The jet and a west to east stationary front were the triggers for thunderstorms that developed later in the day. Rounds of ... | 3 | 2 | $1K | |
| 2012-06-20 | FloodTioga, Clark County Three people were killed in two separate accidents when their vehicles fell into a 12 to 15 foot deep washout area. The washout occurred after rainfall amounts of 1.5 to 2 inches in a short amount of time caused Scott Creek to quickly rise. From damage photos, it appears the creek stayed within its banks, but the ... | 3 | 0 | $26K | |
| 2022-06-13 | FloodWest Allis, Milwaukee County A 10 year old boy fell into rapidly rising waters of a concrete drainage ditch after a thunderstorm with heavy rainfall. His father and neighbor jumped in to help, but all three were swept away and drowned. The boy was found downstream the next day in the Kinnickinnic River. The other two men were found June 16th in ... | 3 | 0 | – | |
| 1998-08-06 | Flash FloodBrookfield, Waukesha County One storm episode: 2 records in 2 places; the totals are the episode's. A monumental flash flood event ravaged adjacent portions of Milwaukee and Waukesha counties during the afternoon and evening hours. For the northwest quarter of Milwaukee Co., and the northeast/ eastcentral parts of Waukesha Co., it was the second year in row (press headline - "deja vu all over again"). In Milwaukee ... | 2 | 2 | $71M | |
| 2025-08-09 | Flash FloodCarrollville, Milwaukee County One storm episode: 17 records in 4 places, 2025-08-09 to 2025-08-11; the totals are the episode's. A historic flash flood and record rainfall occurred over portions of the Milwaukee Metropolitan Area and Southeast WI resulting in damages in the $100s Millions. Warm, moist, and unstable air rose along a stalled front to produce numerous thunderstorms and more than 10 inches of rain in many locations. Widespread ... | 2 | 2 | $172M | |
| 2016-09-22 | Flash FloodViroqua Municipal Airport, Vernon County One storm episode: 7 records in 6 places; the totals are the episode's. One person was killed near Victory (Vernon County) when a house was swept down a hillside by a mudslide during the early morning hours of the 22nd. Another person drowned south of Viroqua (Vernon County) when the driver of a truck pulling a cattle trailer attempted to drive through flood waters during the afternoon or ... | 2 | 0 | $26M | |
| 2020-05-17 | FloodLake Church, Ozaukee County One storm episode: 2 records; the totals are the episode's. A slow moving low pressure area brought a 18-24 hour period of moderate to sometimes heavy rainfall. 3 to 6 inches of rain fell over far eastern WI, which resulted in river, creek, and lowland flooding. Numerous roads were flooded and closed. A small number of water rescues were executed. One indirect death occurred ... | 1 | 2 | $34K | |
| 2019-04-18 | FloodMarinette County Runoff from rainfall and snow melt led to minor flooding and rapid flows on the Menominee River near and downstream from McAllister. Shortly before the flooding subsided, a fishing boat capsized in Marinette causing two men to fall into the river. One was rescued shortly thereafter and was treated and released from ... | 1 | 1 | – | |
| 2000-09-10 | Flash FloodEau Claire County Motorist drove around police barricades with vehicle and driver subsequently falling into sinkhole. The Eau Claire Leader-Telegram cited 159 reports of residential damage, and 10 reports of damage to businesses in Eau Claire County. Estimated damages within the city of 1.5 million according to the Public Works ... | 1 | 1 | $5.7M | |
| 2007-08-18 | Flash FloodRichland Center, Richland County One storm episode: 17 records in 5 places, 2007-08-18 to 2007-08-19; the totals are the episode's. A warm front lifting northward into Iowa triggered round after round of thunderstorms leading to excessive rainfall across southwest Wisconsin during the evening and overnight hours of August 18-19. Total rainfall amounts of 10 to 15 inches were common. Specific reports from weather observers included 10.12 inches and ... | 1 | 0 | $119M |
Source: NOAA NCEI Storm Events Database: deaths direct and indirect, as filed by the National Weather Service, summed over each storm (one episode, or one named storm filed by several offices). Storm names from the titles of FEMA declarations that name the storm's counties.
The costliest floods and flash floods in Wisconsin
| Date | Record | Character | Killed | Injured | Damage |
|---|---|---|---|---|---|
| 2008-06-08 | Flash FloodLake Mills, Jefferson County One storm episode: 13 records in 12 places; the totals are the episode's. | 0 | 0 | $556M | |
| 2004-06-01 | FloodFond du Lac County · forecast zone Fond Du Lac One storm episode: 20 records in 20 places; the totals are the episode's. | 0 | 0 | $339M | |
| 2025-08-09 | Flash FloodCarrollville, Milwaukee County One storm episode: 17 records in 4 places, 2025-08-09 to 2025-08-11; the totals are the episode's. | 2 | 2 | $172M | |
| 1997-06-21 | Flash FloodFox Pt, Milwaukee County | 0 | 0 | $145M | |
| 2008-06-12 | Flash FloodWales, Waukesha County One storm episode: 9 records in 9 places; the totals are the episode's. | 1 | 0 | $142M | |
| 2018-08-28 | Flash FloodUnion Center, Juneau County One storm episode: 11 records in 6 places; the totals are the episode's. | 0 | 0 | $126M | |
| 2007-08-18 | Flash FloodRichland Center, Richland County One storm episode: 17 records in 5 places, 2007-08-18 to 2007-08-19; the totals are the episode's. | 1 | 0 | $119M | |
| 1996-06-16 | FloodOutagamie County · forecast zone Outagamie One storm episode: 3 records in 3 places; the totals are the episode's. | 0 | 0 | $105M |
Source: NOAA NCEI Storm Events Database: property and crop damage as estimated by the National Weather Service, in 2025 dollars.
Are floods and flash floods becoming more frequent in Wisconsin?
Wisconsin's count per decade against the whole country's, and its share. NOAA recorded every event type only from 1996, so earlier decades are not comparable; the share of the national total is the fairer comparison across decades.
| Decade | Wisconsin | United States | Wisconsin's share |
|---|---|---|---|
| 1996-99 | 277 | 20,986 | 1.3% |
| 2000s | 701 | 54,913 | 1.3% |
| 2010s | 1,148 | 68,322 | 1.7% |
| 2020-26 | 454 | 43,563 | 1.0% |
Source: NOAA NCEI Storm Events Database.
The most recent floods and flash floods in Wisconsin
| Date | Record | Character | Killed | Injured | Damage |
|---|---|---|---|---|---|
| 2026-06-24 | Flash FloodCormier, Brown County | 0 | 0 | – | |
| 2026-06-11 | FloodSharon, Walworth County | 0 | 0 | – | |
| 2026-06-11 | FloodBrodhead, Green County | 0 | 0 | – | |
| 2026-05-01 | FloodBusseyville, Jefferson County | 0 | 0 | $1K | |
| 2026-05-01 | FloodFt Atkinson, Jefferson County | 0 | 0 | $1K | |
| 2026-04-19 | FloodCharlie Bluff, Rock County | 0 | 0 | $1K | |
| 2026-04-18 | FloodMuscoda, Grant County | 0 | 0 | – | |
| 2026-04-18 | FloodBusseyville, Jefferson County | 0 | 0 | $1K | |
| 2026-04-17 | Flash FloodSturtevant Sylvania, Racine County | 0 | 0 | $2K | |
| 2026-04-17 | Flash FloodButler, Milwaukee County | 0 | 0 | – | |
| 2026-04-17 | Flash FloodDowntown Janesville, Rock County | 0 | 0 | $30M | |
| 2026-04-17 | FloodRubicon, Dodge County | 0 | 0 | $5K |
Source: NOAA NCEI Storm Events Database, records through June 30, 2026; the newest months are revised by NCEI as reports arrive. Search the record at NCEI.
Federal disaster declarations for floods and flash floods in Wisconsin
FEMA has declared 41 disasters in Wisconsin for floods and flash floods, counting its incident type and declarations that name flood in the title (FEMA files most storm disasters under Severe Storm); 40 were major disasters, the latest on June 30, 2026.
| Declared | Number | Title | Areas named |
|---|---|---|---|
| 2026-06-30 | DR-4923 | Severe Storms, Tornadoes, and Flooding | 22 |
| 2025-09-11 | DR-4892 | Severe Storms, Straight-Line Winds, Flooding, and Mudslides | 3 |
| 2020-03-11 | DR-4477 | Severe Winter Storm and Flooding | 3 |
| 2019-08-27 | DR-4459 | Severe Storms, Tornadoes, Straight-Line Winds, and Flooding | 20 |
| 2018-10-18 | DR-4402 | Severe Storms, Tornadoes, Straight-Line Winds, Flooding, and Landslides | 14 |
| 2018-08-10 | DR-4383 | Severe Storms, Straight-Line Winds, and Flooding | 6 |
| 2017-10-07 | DR-4343 | Severe Storms, Straight-Line Winds, Flooding, Landslides, and Mud | 11 |
| 2016-10-20 | DR-4288 | Severe Storms, Flooding, and Mudslides | 10 |
| 2016-08-09 | DR-4276 | Severe Storms and Flooding | 9 |
| 2013-08-08 | DR-4141 | Severe Storms, Flooding, and Mudslides | 8 |
| 2012-08-02 | DR-4076 | Severe Storms and Flooding | 4 |
| 2010-10-21 | DR-1944 | Severe Storms and Flooding | 9 |
Source: FEMA OpenFEMA Disaster Declarations Summaries (v2), through October 2, 2026. OpenFEMA dataset page.
Next
- Milwaukee County: the county's whole recordThe Wisconsin county with the most floods and flash floods per square mile
- Floods across the United StatesEvery state ranked, by year and month
- Every natural hazard in WisconsinTornadoes, floods, storms, heat and the federal declarations
- Severe thunderstorm wind in Wisconsin13,005 records
- Winter storms in Wisconsin10,237 records
- Hail in Wisconsin9,265 records