Home › Illinois › Brown County

Brown County, Illinois

Natural disaster risk, federal disaster history and flood insurance facts.

Very Low overall risk
101st of 102highest risk in Illinois
$3Mexpected losses a year
14federal declarations
1 in 500homes with flood insurance
Photo: Bold Frontiers, CC BY 2.0

Brown County, Illinois has a very low overall risk from natural hazards in FEMA's National Risk Index. Its risk score is lower than 95% of US counties. It ranks 101st of 102 counties in Illinois. The costliest hazards here are cold waves, heat waves and inland flooding. FEMA estimates about $3.2 million a year in expected losses, or roughly $508 per resident. Since 1973 it has been included in 14 federal disaster or emergency declarations for natural events (11 major disasters). The most recent was in May 2013 (severe storms, straight-line winds and flooding). Only 4 homes here carry federal flood insurance. Since 1978, federal flood insurance has paid about $438,000 on 32 claims here.

FEMA National Risk Index December 2025; OpenFEMA declarations to Nov 6, 2026; NFIP records. Updated November 6, 2026.

Top risks in Brown County

$922,011 a yearExpected losses. Damaging events about 4 times a year.
  • Insulate pipes in outside walls, crawl spaces and garages.
  • Know how to shut off the main water valve.
$686,342 a yearExpected losses. Damaging events about 8 times a year.
  • Check that cooling works before summer.
  • Know where the nearest cooling center is.
$652,947 a yearExpected losses. Damaging events about once every 2 years.
  • Check the FEMA flood map for your address, and ask the seller or landlord about past flooding.
  • Price a flood policy now. Most new federal policies take 30 days to start.
HazardRatingScoreExpected loss a year
Cold waveLow48.2
$922K
Heat waveLow62.6
$686K
Inland floodingVery Low4.1
$653K
Strong windLow25.0
$249K
DroughtLow54.9
$216K
TornadoVery Low17.7
$206K
HailVery Low22.8
$87K
EarthquakeVery Low28.0
$64K
LightningVery Low12.0
$43K
LandslideLow78.6
$15K
Ice stormVery Low16.0
$11K
Winter weatherVery Low12.0
$10K
HurricaneVery Low9.1
$2K
WildfireVery Low0.2
$84

Scores are percentiles: a score of 90 means higher risk than about 90% of US counties for that hazard. Hazards FEMA does not rate here are left out. Social vulnerability is relatively low and community resilience is relatively high in FEMA's measures.

Federal disaster history

Recent disasters nationwide ›

Declarations by decade

Federal declarations for natural events that included Brown County. 2020s bar runs to November 2026.

By type

Flood5
Severe Storm4
Snowstorm3
Tornado1
Hurricane1

Most recent

May 10, 2013Severe Storms, Straight-Line Winds, and FloodingMajor disaster
Mar 17, 2011Severe Winter Storm and SnowstormMajor disaster
Dec 29, 2006SnowEmergency
Sep 7, 2005Hurricane Katrina EvacuationEmergency
May 15, 2003Severe Storms, Tornadoes, and FloodingMajor disaster
May 21, 2002Severe Storms, Tornadoes and FloodingMajor disaster
Jan 8, 1999Il-Winter Storm 1/1/99Emergency
May 6, 1996Severe Storms and FloodingMajor disaster
May 30, 1995Severe Storms and FloodingMajor disaster
Jul 9, 1993Severe Storms & FloodingMajor disaster
Show all 14
Dec 13, 1982Severe Storms, Tornadoes & FloodingMajor disaster
Apr 30, 1979Severe Storms & FloodingMajor disaster
Jun 10, 1974Severe Storms & FloodingMajor disaster
Apr 26, 1973Severe Storms & FloodingMajor disaster

Illinois also had 2 statewide declarations that did not name single counties.

Storm history since 1955

Tornado risk by county ›

The National Weather Service has logged 145 storm reports in Brown County since 1955, with 1 death and 22 injuries and about $3.4 million in reported damage. The strongest on record here was an F2 tornado on October 14, 1966.

10tornadoes
52hail reports, largest 2.75 inches
68damaging thunderstorm winds
15floods and flash floods

Strongest tornadoes

DateStrengthNearHurt / killed
Oct 14, 1966F2–20 / 0
Apr 27, 1956F2–0 / 0
Mar 26, 1959F2–0 / 0
May 10, 2003F2Timewell0 / 0
Sep 26, 1959F1–0 / 0

Most damaging storms

DateTypeNearDamage
Oct 14, 1966Tornado–$3M
Jul 9, 2021Thunderstorm WindMt Sterling$300K
Sep 26, 1959Tornado–$250K
Jul 9, 2021HailMt Sterling$100K
Jun 25, 2024Thunderstorm WindVersailles$30K
Dec 3, 1955Tornado–$25K

Source: NOAA Storm Events Database, county-based reports through Apr 17, 2026. Tornado records start in 1950, hail and wind in 1955, and floods and other storm types in 1996, so older decades undercount. Damage is in dollars of the year it happened and is often an estimate. Winter storms, heat and hurricanes are logged by forecast zone, not county, so they are not counted here.

Flood insurance in Brown County

Check your address flood zone ›
0.2%of homes have federal flood insurance (4 policies)
13.3%of homes in mapped high-risk flood zones are insured
$438,494paid on 32 flood claims since 1978
2013costliest year, with $112,658 paid

National Flood Insurance Program (NFIP) records only; private flood policies are not included. Home counts as of Aug 3, 2026. Since 2021 NFIP prices each home separately under Risk Rating 2.0, so your price depends on the building, not the county. Ask an agent for a quote.

Homes in Brown County

$150,300median home value (Illinois $263,300, US $332,700)
1960median year homes were built (Illinois 1971, US 1980)
74%of homes built before 1980, before many modern wind, quake and flood building rules
5%of homes are mobile homes, which are the least safe in tornadoes and high winds

Older homes and mobile homes usually suffer more damage in storms, floods and earthquakes, and can cost more to insure. If you are buying, ask about roof age, foundation bolting and any retrofits. Source: US Census Bureau, American Community Survey 2020 to 2024 5-year estimates; 2,321 housing units.

Compare in Illinois

All 102 ›
Largest countiesOverall riskTop hazard
Cook CountyVery HighInland flooding
DuPage CountyHighInland flooding
Lake CountyHighInland flooding
Will CountyHighInland flooding
Kane CountyHighInland flooding
McHenry CountyModerateInland flooding
Winnebago CountyModerateInland flooding
Madison CountyModerateInland flooding

Neighboring counties

CountyOverall riskDeclarations
Adams CountyLow19
Morgan CountyLow15
Pike CountyVery Low23
Cass CountyVery Low19
Schuyler CountyVery Low16

Common questions about Brown County

What is the biggest natural hazard in Brown County?

Cold wave has the highest expected yearly losses in Brown County, about $922,011 a year in FEMA's estimate. Heat wave is second at $686,342.

How many federal disasters has Brown County had?

Brown County has been included in 14 federal disaster or emergency declarations for natural events since 1973, including 11 major disasters. The most recent was Severe Storms, Straight-Line Winds, and Flooding in May 2013.

Is Brown County a high-risk place to live?

Its overall rating is Very Low, 101st highest of 102 in Illinois. A county rating covers the whole area. Risk at one address can be much higher or lower, so check the FEMA flood map and ask about the home's history.

Do I need flood insurance in Brown County?

Standard home insurance does not cover flooding. About 1 in 500 homes in Brown County has federal flood insurance. Lenders require it in mapped high-risk zones, but many flood claims come from outside those zones.

How many tornadoes has Brown County had?

NOAA records list 10 tornadoes in Brown County since 1950. The strongest was an F2 tornado on October 14, 1966. The weather service has also logged 52 hail reports and 15 floods here.

Sources: FEMA National Risk Index (December 2025), OpenFEMA Disaster Declarations Summaries, and NFIP policy and claims data. Hazard Compass is independent and not affiliated with FEMA. These figures describe the whole county, not a single property, and are not insurance or safety advice. Report a problem.