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

Brown County Disaster Risk

Brown County, Wisconsin

FEMA Risk Rating

Relatively Moderate

National Percentile

90th

of 3,144 counties

State Rank

#3

of 72 (1 = highest risk)

Flood Risk

92th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Moderate

Higher than 92% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Very Low

Higher than 34% of US counties

Tornado

Tornado and severe thunderstorm risk

Moderate

Higher than 93% of US counties

Earthquake

Seismic activity and ground shaking risk

Very Low

Higher than 35% of US counties

Hurricane

Tropical cyclone and hurricane risk

Very Low

Higher than 26% of US counties

Risk Overview

About Natural Disaster Risk in Brown County, Wisconsin

Brown County faces highest state risk

Brown County scores 90.04 on the composite risk scale, ranking it in the Relatively Moderate category and far above Wisconsin's state average of 59.08. This Green Bay–area county faces the most comprehensive natural disaster exposure of any Wisconsin county measured.

Wisconsin's riskiest county by far

Brown County ranks as the highest-risk county in Wisconsin with a composite score of 90.04, dramatically exceeding the state average of 59.08. No other Wisconsin county faces comparable multi-hazard exposure.

Significantly riskier than surrounding areas

Brown County's 90.04 score far exceeds neighboring Calumet County (30.18) and most other regional peers, reflecting its unique geographic and demographic vulnerabilities. This stark difference highlights Brown County's exceptional risk profile within eastern Wisconsin.

Tornadoes and floods dominate threats

Brown County faces exceptional tornado risk at 93.42 and extreme flood risk at 91.86—among the highest in the nation for both hazards. Earthquake risk (35.34) and hurricane risk (26.12) add secondary but notable threats across the county.

Comprehensive coverage is non-negotiable

Brown County residents must carry robust homeowners insurance with explicit tornado and flood coverage, plus consider a separate flood insurance policy through the NFIP. Given the county's multifaceted risk exposure, consulting with an insurance professional about earthquake and hurricane coverage is also prudent.

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

Preparedness Guide

What to Prepare for in Brown County

Top Hazards by Exposure

  1. #1
    TornadoPrepare
    93th percentile
  2. #2
    FloodPrepare
    92th percentile
  3. #3
    EarthquakePrepare
    35th percentile

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

Risk Advisory: Brown County

Risk Verdict

FEMA's National Risk Index rates Brown County at the 90th percentile nationally — above average and worth proactive preparation. Residents should prioritize a formal household emergency plan, including evacuation routes, insurance review, and a well-stocked emergency kit.

Hazard Breakdown

Tornado risk is Brown County's dominant natural hazard, ranked at the 93th percentile nationally under FEMA's National Risk Index. Flood ranks second at the 92th percentile nationally. Additional tracked hazards include earthquake (35th percentile), wildfire (34th percentile), hurricane (26th percentile).

Preparedness Context

With tornado ranked at the 93th percentile nationally, Brown County sits in a high-exposure zone where the difference between outcomes often comes down to proximity to a reinforced interior shelter and seconds of warning time. Alongside tornado exposure, flood at the 92th percentile nationally means Brown County households face multi-hazard severe-weather seasons that benefit from a single integrated emergency plan covering both threats. For Brown County households, safe rooms certified to FEMA 320/361 standards offer the highest protection during a direct tornado hit; households without a safe room should locate the innermost lowest-floor room in their building and practice the route to it before storm season.

Regional Context

Brown County is 31.0 composite risk points above the Wisconsin average, indicating that residents face greater natural hazard exposure than most of their in-state neighbors.

Is your household prepared for Brown 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 Brown County, WI?
Brown County has a FEMA National Risk Index rating of Relatively Moderate, placing it in the 90th 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 Brown County?
Brown County is evaluated for five major natural hazard types: tornado (93th percentile), flooding (92th percentile), earthquake (35th percentile), wildfire (34th percentile), hurricane (26th percentile). The highest-risk hazard is tornado at the 93th 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 Brown County risk compare to the Wisconsin average?
Brown County's composite risk percentile is 90th, compared to the Wisconsin state average of 59th percentile. The state's overall risk rating is Relatively Low. This means Brown County faces higher natural disaster risk than the typical county in Wisconsin.
Is Brown County at risk for tornado?
Yes, Brown County's tornado risk is at the 93th percentile nationally. This places it in the top quartile for this hazard type. For flooding specifically, Brown County is at the 92th 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 Brown County higher risk than average?
Brown County's composite risk score of 90th percentile is above the Wisconsin state average of 59th percentile. This elevated risk is driven by tornado exposure (93th 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.