215 flood insurance claims·$4.0M paid·1 federal flood & hurricane disasters
Share of the whole county outline, rivers and lakes included; parts FEMA hasn’t mapped count as zero.
Shaded areas are FEMA’s mapped flood hazard zones in and around Winnebago County, Wisconsin. Zoomed out they are simplified; at street level the map switches to FEMA’s exact layer. Tap anywhere to check that spot, or search an address above.
Flash flooding from summer thunderstorms dominates the flood profile of Winnebago County, supported by 12 flood events and 6 flash flood events recorded in the NOAA Storm Events Database over the last 30 years. Torrential rainfall from these systems routinely generates 2 to 5 inches of rain, covering streets in flowing water and triggering closures. For example, severe thunderstorms on August 28, 2018, produced torrential rainfall causing urban and flash flooding in the Fox Valley, while storms on July 16, 2025, dropped 2 to over 5 inches of rain that covered streets with flowing water and forced multiple street closures.
NFIP claim records demonstrate that flood risk extends beyond designated high-risk areas. Zone A accounts for 130 claims with an average payout of $30,540 and an average recorded water depth of 8 inches. Meanwhile, Zone X properties recorded 56 claims with an average payout of $28,779 and an average water depth of 8 inches. Additional claims occurred in Zone X_UNSHADED, Zone X_SHADED, and unknown zones. Homeowners and real estate agents in Zone A face the highest concentration of historical claims, but properties in Zone X also require close attention given the substantial claim volume and average water depths recorded outside designated high-risk zones.
Summary written from NOAA storm reports and NFIP claims for this county. Not a prediction.
12% of Winnebago County’s flood insurance claims were on properties rated outside FEMA’s high-risk zones.
149 NFIP claims with a recorded rated flood zone, 1978 to date. The zone is the one FEMA used to rate that policy, which may not match today’s map. Source: OpenFEMA NFIP claims.
In flood insurance claims here that reported a flood depth, the average was 8 inches.
Drawn to scale against an 80-inch door. Even a few inches soaks flooring, the bottom of the drywall and anything plugged in near the floor.
Average of the depths reported on claims (zero and implausible values left out); FEMA’s record doesn’t say exactly where each depth was measured. Source: OpenFEMA NFIP claims.
The worst year was 2008, with 52 claims and $2.4M paid, the year of Severe Storms, Tornadoes, and Flooding.
Bar height is scaled by square root so ordinary years stay visible next to the worst one. NFIP claims by year of loss. Source: OpenFEMA.
7 NOAA storm reports from Winnebago County describe what happened, in the words of the forecasters who covered it. Read the Wisconsin flood stories →
11 federal disaster declarations since 1974, 1 of them floods, coastal storms or hurricanes.
| Disaster | Began |
|---|---|
| Severe Storms, Tornadoes, And Flooding | Jun 5, 2008 |
| Hurricane Katrina Evacuation | Aug 29, 2005 |
| Severe Storms And Flooding | May 7, 2004 |
| Flooding, Severe Storms And Tornadoes | Apr 10, 2001 |
| Severe Storms, Tornadoes & Flooding | Jun 7, 1993 |
| Severe Storms, Tornadoes & Flooding | Jun 22, 1990 |
| Drought | Jun 17, 1976 |
| Tornadoes | Apr 26, 1974 |
Weather and water disasters only; most recent first. Source: OpenFEMA Disaster Declarations.
18 since 1996: 6 flash floods and 12 river or area floods.
| Event | Date | Damage |
|---|---|---|
| Flash Flood | Jul 16, 2025 | — |
| Flood | Aug 28, 2018 | $2,000 |
| Flood | Jun 12, 2017 | $2,000 |
| Flash Flood | May 3, 2012 | $200,000 |
| Flash Flood | Jul 14, 2010 | — |
| Flash Flood | Jun 12, 2008 | $18.6M |
| Flood | Jun 8, 2008 | $625,000 |
| Flood | May 21, 2004 | — |
— = no damage estimate in the record. Source: NOAA Storm Events Database.
Flash Flood · Jul 16, 2025. Showers and thunderstorms tracked through central and east-central Wisconsin during the afternoon and evening on Wednesday (7/16) as a mesoscale convective vortex tracked along a cold front through southern Wisconsin. This system brought a brief period of heavy rainfall with rainfall amounts of 2 to 4 inches and locally higher amounts exceeding 5 inches across the area. The heavy rain in a short period caused fl…
Flood · Aug 28, 2018. Severe thunderstorms produced wind damage, including a tornado, over east-central Wisconsin. Numerous trees were snapped or uprooted and power lines downed. The storms also produced torrential rainfall that caused urban flooding and flash flooding in parts of the Green Bay area and Fox Valley. There were numerous reports of 2 to 4 inches of rain, along with a few even higher totals.
Flood · Jun 12, 2017. A stalled front across central and east central Wisconsin was the focus for severe thunderstorms. Storms developed in southern Minnesota and a bow echo formed that made its way across Wisconsin south of Highway 29. The worst damage was around Stevens Point (Portage Co.) where thunderstorm winds downed numerous trees and power lines. Power was knocked out to 15,000 to 18,000 customers. The storms also brought torre…
Flash Flood · May 3, 2012. Thunderstorms developed over northeast Iowa Wednesday evening before tracking over east central Wisconsin overnight on May 2nd into the morning of May 3rd. Rainfall measurements for the 24 hour period ending around 7 am CDT indicated a widespread 2 to 4.5 inches of rain over east central Wisconsin. A roughly 15 mile wide core of higher rainfall amounts, more than 4 inches, fell from Berlin to Omro to Oshkosh to…
National Weather Service narratives, lightly trimmed. Source: NOAA Storm Events Database.
Every colour on the map above is a place on this drawing: where the ground sits relative to the flood FEMA plans for.
If a building in Winnebago County is in a high-risk zone (A or V) and its mortgage comes from a federally regulated or insured lender, or is federally backed, flood insurance is required.
Outside those zones it is optional, and often worth having: from 2014 to 2024 nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area. Since Risk Rating 2.0, NFIP premiums are set for each building, so the only reliable price is a quote: FloodSmart.gov or a local agent.