Enter any address in Washington County, Wisconsin to see its FEMA flood zone
Flash flooding from intense rainfall events is the primary flood concern in Washington County, WI. Over the past 30 years, NOAA Storm Events data shows 12 flash flood events and 11 general flood events, with one recorded fatality. For example, a historic flash flood event in August 2025 brought record rainfall and widespread flooding to streets, creeks, and low-lying neighborhoods, contributing to damages in the hundreds of millions across Southeast Wisconsin.
National Flood Insurance Program (NFIP) claims data indicates that properties in Zone A, which are areas with a 1% annual chance of flooding, have the highest number of claims at 42, with an average payout of $12,231 and an average water depth of 2.3 feet. However, properties in Zone X, areas with a 0.2% annual chance of flooding, have experienced significantly higher average payouts of $47,038, despite an average water depth of 1.3 feet. Homeowners in Zone X_SHADED also experienced substantial payouts with an average water depth of 2.5 feet.
Residents in areas designated as Zone A, as well as those in Zone X and Zone X_SHADED, should pay close attention to flood risk. Properties located near creeks, rivers, or in low-lying areas are particularly susceptible to the impacts of both flash flooding and general flood events.
Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.
19 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.
Washington County, Wisconsin has recorded 23 flood-related events since 1996 according to NOAA's Storm Events Database, including 12 flash floods and 11 river or area floods. The county has received 13 federal disaster declarations, 3 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.
FEMA Disaster Declarations (1976–2025)
Source: OpenFEMA Disaster Declarations Summaries.
| Declaration | Type | Date |
|---|---|---|
| Severe Storms, Straight-line Winds, Flooding, And Mudslides | Flood | Aug 9, 2025 |
| Covid-19 | Biological | Jan 20, 2020 |
| Covid-19 Pandemic | Biological | Jan 20, 2020 |
| Severe Winter Storm And Snowstorm | Snowstorm | Jan 31, 2011 |
| Severe Storms, Tornadoes, And Flooding | Severe Storm | Jun 5, 2008 |
| Record Snow And Near Record Snow | Snowstorm | Feb 5, 2008 |
| Hurricane Katrina Evacuation | Hurricane | Aug 29, 2005 |
| Severe Storms And Flooding | Severe Storm | May 7, 2004 |
| Severe Storms And Flooding | Severe Storm | Jun 21, 1997 |
| Severe Storms & Hail | Severe Storm | Jul 7, 1991 |
NOAA Storm Events Database (1996–2025)
Source: NOAA National Weather Service Storm Events Database.
| Type | Date | Damage |
|---|---|---|
| Flood | Aug 10, 2025 | 1.00M (1 deaths) |
| Flash Flood | Aug 10, 2025 | 2.40M |
| Flash Flood | Apr 19, 2023 | 20.00K |
| Flood | Aug 27, 2018 | 1.00K |
| Flash Flood | Aug 27, 2018 | 584.00K |
| Flood | Feb 20, 2018 | 0.00K |
| Flash Flood | Jul 22, 2010 | 20.00K |
| Flash Flood | Apr 25, 2008 | 10.00K |
| Flash Flood | Jun 8, 2008 | 5.13M |
| Flash Flood | Aug 22, 2007 | 100.00K |
Flood — Aug 10, 2025
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 flash flooding of streets, creeks, rivers, and low lying neighborhoods occurred. A...
Flash Flood — Aug 10, 2025
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 flash flooding of streets, creeks, rivers, and low lying neighborhoods occurred. A...
Flash Flood — Apr 19, 2023
A surge of relatively mild, moist, and unstable air aloft brought rounds of strong to severe thunderstorms to southern WI. Numerous reports of large hail were received. Flash flooding and general flooding occurred in urban areas.
Flood — Aug 27, 2018
Multiple rounds of strong to severe thunderstorms moved across southern WI as a warm front slowly moved north through the region. Flash flooding occurred in Washington, Ozaukee, and northern Milwaukee Counties which was followed by prolonged river flooding. Four to eight inches of rain had fallen over this area. The thunderstorms produced sporadic tree and power line damage across southern WI.
Flash Flood — Aug 27, 2018
Multiple rounds of strong to severe thunderstorms moved across southern WI as a warm front slowly moved north through the region. Flash flooding occurred in Washington, Ozaukee, and northern Milwaukee Counties which was followed by prolonged river flooding. Four to eight inches of rain had fallen over this area. The thunderstorms produced sporadic tree and power line damage across southern WI.
Source: NOAA National Weather Service Storm Events Database.
Source: OpenFEMA NFIP Individual Claims (2.25M records analyzed).
FEMA assigns flood zone designations to areas in Washington County, Wisconsin:
AE High Risk — 1% annual chance of flooding. Insurance required.
VE Very High Risk — Coastal flooding with wave action.
X (Shaded) Moderate Risk — 500-year floodplain.
X Low Risk — Outside major floodplains.
Properties in Washington County, Wisconsin that are in FEMA-designated Special Flood Hazard Areas (zones A and V) with federally backed mortgages are required to carry flood insurance.
Even outside high-risk zones, flood insurance is recommended. From 2014 to 2024, nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area.
Visit FloodSmart.gov to find an agent and get a quote.