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Boone County, Illinois

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

Relatively Low overall risk
47th of 102highest risk in Illinois
$21Mexpected losses a year
9federal declarations
1 in 333homes with flood insurance
Photo: U.S. Geological Survey, public domain

Boone County, Illinois has a relatively low overall risk from natural hazards in FEMA's National Risk Index. Its risk score is higher than 57% of US counties. It ranks 47th of 102 counties in Illinois. The costliest hazards here are inland flooding, tornadoes and cold waves. FEMA estimates about $21 million a year in expected losses, or roughly $400 per resident. Since 1967 it has been included in 9 federal disaster or emergency declarations for natural events (4 major disasters). The most recent was in March 2011 (severe winter storm and snowstorm). Fewer than 1 in 100 homes here carry federal flood insurance (62 policies). Since 1978, federal flood insurance has paid about $271,000 on 46 claims here.

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

Top risks in Boone County

$11.3 million a yearExpected losses. Damaging events about once a year.
  • 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.

Tornado

Moderate
$3.8 million a yearExpected losses. Damaging events about once every 4 years.
  • Pick a shelter spot: a basement, or an inside room on the lowest floor with no windows.
  • Turn on emergency alerts on your phone and keep a weather radio.

Cold wave

Moderate
$3.2 million a yearExpected losses. Damaging events about 6 times a year.
  • Insulate pipes in outside walls, crawl spaces and garages.
  • Know how to shut off the main water valve.
HazardRatingScoreExpected loss a year
Inland floodingLow63.9
$11M
TornadoModerate77.6
$4M
Cold waveModerate76.3
$3M
HailModerate79.6
$933K
Strong windModerate59.9
$800K
LightningModerate68.6
$515K
Heat waveLow46.8
$350K
EarthquakeVery Low45.6
$234K
DroughtLow49.5
$153K
Winter weatherLow41.1
$52K
Ice stormLow32.2
$40K
WildfireVery Low8.3
$3K
HurricaneVery Low8.8
$2K
LandslideVery Low28.1
$291

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 Boone County. 2020s bar runs to November 2026.

By type

Snowstorm5
Flood2
Tornado1
Hurricane1

Most recent

Mar 17, 2011Severe Winter Storm and SnowstormMajor disaster
Mar 13, 2008Record Snow and Near Record SnowEmergency
Dec 29, 2006SnowEmergency
Sep 7, 2005Hurricane Katrina EvacuationEmergency
Jan 17, 2001Illinois Winter Snow StormsEmergency
Jul 9, 1993Severe Storms & FloodingMajor disaster
Jan 16, 1979Blizzards & SnowstormsEmergency
Apr 26, 1973Severe Storms & FloodingMajor disaster
Apr 25, 1967TornadoesMajor disaster

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

Storm history since 1959

Tornado risk by county ›

The National Weather Service has logged 271 storm reports in Boone County since 1959, with 26 deaths and 454 injuries and about $8.3 million in reported damage. The strongest on record here was an F4 tornado on April 21, 1967.

25tornadoes
65hail reports, largest 2 inches
143damaging thunderstorm winds
31floods and flash floods

Strongest tornadoes

DateStrengthNearHurt / killed
Apr 21, 1967F4–410 / 24
Jan 7, 2008EF3Poplar Grove4 / 0
Nov 22, 2010EF2Argyle0 / 0
Mar 31, 2023EF1Irene40 / 1
Apr 9, 2015EF1Herbert0 / 0

Most damaging storms

DateTypeNearDamage
Nov 22, 2010TornadoArgyle$5M
Jan 7, 2008TornadoPoplar Grove$2M
Aug 25, 2006Thunderstorm WindBelvidere$400K
Apr 21, 1967Tornado–$250K
Apr 12, 2014HailBelvidere$250K
Apr 9, 2015TornadoHerbert$150K

Source: NOAA Storm Events Database, county-based reports through Jun 11, 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 Boone County

Check your address flood zone ›
0.3%of homes have federal flood insurance (62 policies)
25.7%of homes in mapped high-risk flood zones are insured
$271,254paid on 46 flood claims since 1978
2013costliest year, with $76,852 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 Boone County

$216,900median home value (Illinois $263,300, US $332,700)
1986median year homes were built (Illinois 1971, US 1980)
45%of homes built before 1980, before many modern wind, quake and flood building rules
6%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; 20,291 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
McHenry CountyModerate14
Winnebago CountyModerate17
Rock County, WIModerate14
Walworth County, WILow11
DeKalb CountyLow10
Ogle CountyLow12

Common questions about Boone County

What is the biggest natural hazard in Boone County?

Inland flooding has the highest expected yearly losses in Boone County, about $11.3 million a year in FEMA's estimate. Tornado is second at $3.8 million.

How many federal disasters has Boone County had?

Boone County has been included in 9 federal disaster or emergency declarations for natural events since 1967, including 4 major disasters. The most recent was Severe Winter Storm and Snowstorm in March 2011.

Is Boone County a high-risk place to live?

Its overall rating is Relatively Low, 47th 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 Boone County?

Standard home insurance does not cover flooding. About 1 in 333 homes in Boone 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 Boone County had?

NOAA records list 25 tornadoes in Boone County since 1950. The strongest was an F4 tornado on April 21, 1967. The weather service has also logged 65 hail reports and 31 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.