Brown County, WI
FEMA National Risk Index scores, disaster declarations & hazard data
Brown County has experienced 9 federally declared disasters since 1973, most recently Severe Storms, Tornadoes, And Flooding in 2026. Its overall natural hazard risk is rated Relatively Moderate — near the middle compared to other US counties.
Brown County's highest-rated hazards are cold wave, hail, and lightning, with its top risk rated "Relatively High" by FEMA's National Risk Index. NOAA records 56 storm events in the county over the past decade. Community vulnerability is relatively low (30th percentile nationally), indicating stronger recovery capacity than most US counties.
Past disasters & FEMA designations
A federal disaster declaration officially designates a county for FEMA disaster assistance. Brown County has been designated in 9 declarations since 1973, covering 5 disaster types including severe storm (3), flood (2), biological (2).
| Year | Type | Event name |
|---|---|---|
| 2026 | Flood | Severe Storms, Tornadoes, And Flooding |
| 2020 | Biological | Covid-19 Pandemic |
| 2020 | Biological | Covid-19 |
| 2005 | Hurricane | Hurricane Katrina Evacuation |
| 2004 | Severe Storm | Severe Storms And Flooding |
| 1993 | Severe Storm | Severe Storms, Tornadoes & Flooding |
| 1990 | Severe Storm | Severe Storms, Tornadoes & Flooding |
| 1976 | Drought | Drought |
| 1973 | Flood | Severe Storms & Flooding |
Source: FEMA OpenFEMA Disaster Declarations Summaries. A single disaster can produce more than one record per county. Data current through September 2026.
Risk by hazard type
| Hazard | Risk rating | Risk score | Recorded events | Deaths | Prop. damage |
|---|---|---|---|---|---|
| Wildfire | Very Low | 33.8 | 0 | 0 | — |
| Inland Flooding | Relatively Moderate | 91.9 | 13 | 0 | $1.7M |
| Coastal Flooding | Relatively Low | 46.4 | 8 | 0 | $455K |
| Earthquake | Very Low | 35.3 | — | — | — |
| Heat Wave | Relatively Low | 76 | 2 | 0 | — |
| Tornado | Relatively High | 93.4 | 3 | 0 | $50K |
| Hurricane | Very Low | 26.1 | 0 | 0 | — |
| Hail | Relatively High | 95.7 | 34 | 0 | — |
| Strong Wind | Relatively Low | 31 | 0 | 0 | — |
| Winter Weather | Relatively Moderate | 83.9 | 0 | 0 | — |
| Ice Storm | Relatively Low | 47.8 | — | — | — |
| Cold Wave | Relatively High | 98.1 | — | — | — |
| Lightning | Relatively High | 95 | 2 | 0 | $55K |
| Drought | No Rating | 0 | 0 | 0 | — |
| Landslide | Very Low | 57.8 | 0 | 0 | — |
| Avalanche | Not Applicable | — | — | — | — |
| Tsunami | Insufficient Data | — | — | — | — |
| Volcanic Activity | Not Applicable | — | — | — | — |
Scores are 0–100 percentiles relative to all US counties — higher means more exposed, not that a disaster is likely this year. Event counts: NOAA Storm Events 2016–2026; earthquake counts from USGS ComCat (M3.0+, 1996–2026). See the methodology page for details.
Community vulnerability
Brown County ranks in the 30th percentile (Low) for community vulnerability — a measure of how hard disaster impacts tend to hit residents. Higher vulnerability means more displacement, worse health outcomes, and slower recovery after a disaster.
| SVI theme | Percentile | Vulnerability level |
|---|---|---|
| Overall | 30th | Low |
| Socioeconomic status | 15th | Very low |
| Household characteristics | 41st | Low |
| Racial & ethnic minority status | 54th | Moderate |
| Housing type & transportation | 54th | Moderate |
Source: CDC/ATSDR Social Vulnerability Index 2022. Percentiles compare counties nationally — higher means more vulnerable relative to other counties. See CDC SVI for full methodology.
Future risk outlook
| Wildfire metric | National percentile | Level |
|---|---|---|
| Burn probability | 7th | Very Low |
| Risk to homes | 7th | Very Low |
| Buildings in direct exposure zone | 25.1% | — |
NOAA tracked 56 weather events in this county over 2016–2025: 29 in 2016–20 vs 27 in 2021–25 (-7% — relatively stable).
Wildfire: USDA Forest Service Wildfire Risk to Communities (RDS-2020-0016-2) — modeled values, not annual forecasts. See wildfirerisk.org. Inland flood and heat projections pending data availability; coastal sea-level projections are available for select coastal counties below — see the data page.
Nearby counties
Frequently asked questions
What natural hazards pose the greatest risk in Brown County?
According to the FEMA National Risk Index, the highest-risk hazards in Brown County, Wisconsin are cold wave, hail, and lightning. The county's overall natural hazard risk is rated Relatively Moderate — near the middle compared to other US counties.
Has Brown County received federal disaster declarations?
Yes. Brown County has received 9 federal disaster declarations since 1973, including declarations in 2026. The most common disaster type on record is severe storm (3 declarations).
Has Brown County had any FEMA disaster declarations in 2024, 2025, or 2026?
Yes. Recent federal disaster declarations for Brown County include Severe Storms, Tornadoes, And Flooding (2026). See the declarations table above for the full history since 1973.
How does Brown County's natural hazard risk compare to nearby counties?
Among neighboring counties, Winnebago County, WI has the highest overall natural hazard risk (Relatively Moderate) and Kewaunee County, WI has the lowest (Very Low). Brown County is rated Relatively Moderate overall.
How is Brown County's composite disaster risk index calculated?
Brown County's composite disaster risk index — officially FEMA's National Risk Index (NRI) — scores every US county on a 0–100 percentile scale across 18 natural hazard types, factoring in expected annual loss, social vulnerability, and community resilience. Brown County's composite score of 90 means its overall natural hazard risk is higher than 90% of US counties.