riskbycounty
FEMA NRI 1.19.0Updated Nov 2023 · Coverage 2014–2023Methodology

Winnebago County Disaster Risk

Winnebago County, Wisconsin

FEMA Risk Rating

Relatively Moderate

National Percentile

87th

of 3,144 counties

State Rank

#6

of 72 (1 = highest risk)

Flood Risk

89th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Moderate

Higher than 89% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Very Low

Higher than 40% of US counties

Tornado

Tornado and severe thunderstorm risk

Moderate

Higher than 91% of US counties

Earthquake

Seismic activity and ground shaking risk

Very Low

Higher than 33% of US counties

Hurricane

Tropical cyclone and hurricane risk

Very Low

Higher than 17% of US counties

Risk Overview

About Natural Disaster Risk in Winnebago County, Wisconsin

Winnebago faces significant risk

Winnebago County scores 86.83 on the composite risk index, placing it in the relatively moderate risk category and 47% above Wisconsin's state average of 59.08. The county ranks among Wisconsin's highest-risk communities for natural disasters.

Top-tier risk statewide

Winnebago ranks at the very top of Wisconsin's risk tier, exceeded only by a handful of counties. Multiple high-impact hazards converge here, particularly tornado and flood exposure.

Winnebago's risk stands apart

Winnebago's composite score of 86.83 closely parallels Waukesha County (88.87) as among the state's riskiest. It significantly exceeds surrounding Waupaca County (67.59) and Waushara County (43.26).

Tornado and flood risks peak here

Tornado risk reaches 91.25 in Winnebago—among Wisconsin's highest threat levels—while flood risk scores 89.34, affecting major urban and surrounding areas. Wildfire risk (40.17) poses secondary concern.

Comprehensive insurance is mandatory

Winnebago residents must secure robust homeowners insurance with strong wind and tornado protection. Flood insurance is critical for the county's extensive flood-prone zones; don't assume you're safe without professional assessment of your property's flood risk.

Source: FEMA National Risk Index · Narrative reviewed by Evan Brooks, Data Editor

Preparedness Guide

What to Prepare for in Winnebago County

Top Hazards by Exposure

  1. #1
    TornadoPrepare
    91th percentile
  2. #2
    FloodPrepare
    89th percentile
  3. #3
    WildfirePrepare
    40th percentile

Source: FEMA National Risk Index v1.19.0 · Percentiles are national (3,144 counties)

Risk Advisory: Winnebago County

Risk Verdict

Winnebago County faces a moderate natural disaster risk profile, ranking at the 87th percentile nationally under FEMA's composite risk model. This risk level calls for more than general awareness: insurance coverage review, a family communication plan, and a prepared go-bag are practical priorities.

Hazard Breakdown

Tornado risk is Winnebago County's dominant natural hazard, ranked at the 91th percentile nationally under FEMA's National Risk Index. Flood ranks second at the 89th percentile nationally. Additional tracked hazards include wildfire (40th percentile), earthquake (33th percentile), hurricane (17th percentile).

Preparedness Context

Tornado risk is Winnebago County's top-ranked natural hazard at the 91th percentile nationally. For Winnebago County households, the most protective action available is identifying a reinforced interior room on the lowest floor — a bathroom, closet, or central hallway away from windows. Flood is the second hazard driver for Winnebago County at the 89th percentile nationally, meaning households should maintain awareness of both severe-weather and flood-specific warning systems. A battery-powered NOAA All Hazards weather radio with an auto-alert tone is the highest-leverage single item for tornado preparedness in Winnebago County, since it delivers warnings even when power is out and phone networks are congested.

Regional Context

Winnebago County's composite risk score sits 27.7 points above the Wisconsin county average, placing it among the more hazard-exposed counties in the state.

Is your household prepared for Winnebago County's hazards?

Review FEMA's county-specific preparedness checklists and emergency planning guides.

FEMA Ready Guide →

Frequently Asked Questions

What is the natural disaster risk in Winnebago County, WI?
Winnebago County has a FEMA National Risk Index rating of Relatively Moderate, placing it in the 87th percentile nationally out of 3,144 counties. This composite score reflects the county's overall exposure to natural hazards including floods, wildfires, tornadoes, earthquakes, and hurricanes, weighted by expected annual loss and social vulnerability.
What types of natural hazards affect Winnebago County?
Winnebago County is evaluated for five major natural hazard types: tornado (91th percentile), flooding (89th percentile), wildfire (40th percentile), earthquake (33th percentile), hurricane (17th percentile). The highest-risk hazard is tornado at the 91th percentile nationally. These scores are derived from FEMA's National Risk Index, which analyzes expected annual loss, social vulnerability, and community resilience for each hazard type.
How does Winnebago County risk compare to the Wisconsin average?
Winnebago County's composite risk percentile is 87th, compared to the Wisconsin state average of 59th percentile. The state's overall risk rating is Relatively Low. This means Winnebago County faces higher natural disaster risk than the typical county in Wisconsin.
Is Winnebago County at risk for tornado?
Yes, Winnebago County's tornado risk is at the 91th percentile nationally. This places it in the top quartile for this hazard type. For flooding specifically, Winnebago County is at the 89th percentile.
How is natural disaster risk measured?
FEMA's National Risk Index (NRI) calculates risk scores for 18 natural hazard types across all U.S. counties and census tracts. The composite score combines Expected Annual Loss (estimated dollar losses from each hazard), Social Vulnerability (demographic factors affecting disaster impact), and Community Resilience (ability to recover). Percentile scores rank each county against all 3,144 U.S. counties, and risk ratings range from Very Low to Very High.
Why is Winnebago County higher risk than average?
Winnebago County's composite risk score of 87th percentile is above the Wisconsin state average of 59th percentile. This elevated risk is driven by tornado exposure (91th percentile), along with flooding risk. Geographic location, terrain, climate patterns, and proximity to flood zones or fault lines all influence a county's risk profile.
By Evan Brooks, Data EditorUpdated Reviewed by Evan Brooks, Data Editor

Data Source

Risk data sourced from the FEMA National Risk Index (NRI). Risk scores are relative rankings (0–100) across all US counties — not absolute risk measures. Higher scores indicate higher relative risk compared to other counties.

Disclaimer: This data is informational only. It is not financial, insurance, or legal advice. Always consult a qualified professional before making insurance or real estate decisions.