County Hazards

States › Illinois › Grundy County

Grundy County, Illinois

Recorded hazard history: storm events since 1950, federal disaster declarations since 1953, flood insurance claims since 1978, and FEMA's risk index.

FIPS 17063 · 52,989 residents (2021) · 418 sq mi · dominant hazard Wind

Hail · 75Tornado · 23Flood · 43Wind · 216Winter · 68
1980-06-01: Hail1989-06-19: Hail1990-06-17: Hail1990-08-19: Hail1990-06-21: Hail1991-07-07: Hail1991-07-07: Hail1991-03-27: Hail1991-05-14: Hail1996-04-12: Hail1996-05-09: Hail1996-04-19: Hail1997-05-18: Hail1999-04-10: Hail2000-05-12: Hail2003-09-26: Hail2003-03-19: Hail2003-06-28: Hail2003-07-06: Hail2003-07-06: Hail2003-08-01: Hail2004-05-23: Hail2004-07-22: Hail2005-03-30: Hail2005-03-30: Hail2005-03-30: Hail2006-03-12: Hail2006-03-12: Hail2006-03-12: Hail2006-05-17: Hail2006-05-29: Hail2007-06-18: Hail2007-05-15: Hail2007-05-15: Hail2007-10-18: Hail2007-05-15: Hail2008-06-15: Hail2008-05-30: Hail2008-05-30: Hail2008-05-30: Hail2011-05-29: Hail2011-04-03: Hail2011-04-03: Hail2011-04-03: Hail2011-08-13: Hail2012-07-01: Hail2012-07-01: Hail2012-05-20: Hail2012-05-20: Hail2012-08-20: Hail2013-06-12: Hail2013-06-12: Hail2013-06-12: Hail2013-11-17: Hail2013-07-10: Hail2013-07-10: Hail2013-07-10: Hail2014-08-26: Hail2015-04-08: Hail2015-06-10: Hail2015-06-07: Hail2015-06-10: Hail2019-03-14: Hail2019-03-14: Hail2019-06-01: Hail2020-08-10: Hail2020-08-10: Hail2022-04-30: Hail2024-05-07: Hail1958-06-08: Tornado1965-11-12: Tornado1973-04-19: Tornado1974-04-03: Tornado1975-05-20: Tornado1984-04-27: Tornado1985-06-15: Tornado1988-04-05: Tornado1988-05-08: Tornado2004-04-20: Tornado2013-05-28: Tornado2013-11-17: Tornado2014-06-30: Tornado2015-06-22: Tornado2015-06-22: Tornado2015-06-22: Tornado2016-06-22: Tornado2016-06-22: Tornado2017-02-28: Tornado2020-05-17: Tornado2020-05-23: Tornado2023-07-28: Tornado2024-07-15: Tornado2007-08-24: Flood2007-08-23: Flood2007-08-23: Flood2008-02-17: Flood2008-09-14: Flood2008-09-15: Flood2008-09-14: Flood2009-03-10: Flood2009-05-26: Flood2009-05-15: Flood2009-07-24: Flood2011-05-28: Flood2012-05-06: Flood2013-04-18: Flood2015-06-13: Flood2015-06-15: Flood2016-08-28: Flood2016-08-28: Flood2016-08-28: Flood2018-02-19: Flood2019-05-01: Flood2019-09-28: Flood2019-09-27: Flood2020-05-17: Flood2020-05-17: Flood2021-07-13: Flood2021-07-12: Flood2021-07-12: Flood2024-01-15: Flood2026-04-03: Flood2026-06-10: Wind2026-06-10: Wind2026-06-10: Wind2026-06-10: Wind2026-06-10: Wind2026-06-10: Wind2026-06-10: Wind2026-06-10: Wind2026-06-10: Wind2026-05-04: Wind2025-07-24: Wind2025-07-24: Wind2025-05-15: Wind2025-05-15: Wind2025-05-15: Wind2025-05-15: Wind2024-07-15: Wind2024-07-15: Wind2024-07-15: Wind2024-07-15: Wind2024-06-25: Wind2023-07-28: Wind2023-07-28: Wind2023-07-28: Wind2023-07-28: Wind2023-04-20: Wind2023-04-20: Wind2023-04-20: Wind2023-04-20: Wind2022-08-29: Wind2021-12-10: Wind2021-09-07: Wind2021-09-07: Wind2021-09-07: Wind2021-09-07: Wind2021-09-07: Wind2021-09-07: Wind2021-08-11: Wind2020-08-10: Wind2020-08-10: Wind2020-08-10: Wind2020-08-10: Wind2020-08-10: Wind2020-08-10: Wind2020-08-10: Wind2020-08-10: Wind2020-08-10: Wind2020-08-10: Wind2020-08-10: Wind2020-08-10: Wind2020-08-10: Wind2020-08-10: Wind2020-07-19: Wind2020-07-19: Wind2020-07-19: Wind2020-07-19: Wind2020-07-19: Wind2020-06-26: Wind2020-06-26: Wind2019-06-30: Wind2017-06-14: Wind2017-03-07: Wind2016-07-23: Wind2015-08-18: Wind2015-06-22: Wind2015-04-09: Wind2014-06-30: Wind2014-06-30: Wind2014-06-30: Wind2014-06-30: Wind2014-05-08: Wind2013-06-24: Wind2013-06-24: Wind2013-06-12: Wind2013-05-30: Wind2013-05-28: Wind2013-05-20: Wind2012-08-04: Wind2012-08-04: Wind2012-07-24: Wind2012-07-24: Wind2012-06-29: Wind2011-09-03: Wind2011-08-02: Wind2011-08-02: Wind2011-06-20: Wind2011-05-11: Wind2011-05-11: Wind2010-07-23: Wind2010-07-23: Wind2010-07-23: Wind2010-07-11: Wind2010-06-18: Wind2010-06-12: Wind2010-06-05: Wind2009-06-19: Wind2009-06-19: Wind2009-06-19: Wind2008-08-04: Wind2008-08-04: Wind2008-07-21: Wind2008-07-21: Wind2008-07-21: Wind2008-07-21: Wind2008-07-21: Wind2008-07-10: Wind2008-07-10: Wind2008-05-30: Wind2008-01-07: Wind2007-08-23: Wind
Grundy County within Illinois. Dots: HailTornadoFloodWind event locations in the kept record. Boundaries: US Census Bureau.

NCEI notes that Storm Data is compiled from a variety of sources including the National Weather Service, other federal, state and local agencies, the media and the public; that property and crop damage figures are estimates; and that some events are recorded by NWS forecast zone rather than by county. FEMA notes that NFIP claim records are redacted and aggregated to protect the privacy of policyholders. NCEI storm records through 30 Jun 2026; OpenFEMA declarations refreshed 1 Oct 2026; NFIP claims as of 8 Sep 2026.

The NCEI record lists 495 events for Grundy County, Illinois, between 1950 and 2026; damaging wind account for the largest share.

That is 118.4 events per 100 square miles, in line with the Illinois figure of 120.2, and 93.4 per 10,000 residents against 52.7 statewide.

32 events fall in the 12 months to 30 Jun 2026. NCEI attributes 6 deaths and 29 injuries to events in the county, with property damage estimated at $96M and crop damage at $21M.

FEMA has designated the county in 15 federal disaster declarations since 1953; the most recent is Covid-19 Pandemic (major disaster, 26 Mar 2020).

National Flood Insurance Program policyholders in the county filed 333 claims since 1978, of which 282 were paid, totalling $6.4M (about $23K per paid claim). FEMA counts 161 residential flood policies in force.

FEMA's National Risk Index rates the county's overall risk as "Relatively Low" and its expected annual loss as "Relatively Low" ($50M a year across 18 hazards).

3 tropical storm or hurricane tracks in the HURDAT2 record passed within 100 miles of the county's centre at tropical-storm strength or more, 0 of them within 50 miles at hurricane strength.

32events, last 12 monthsto 30 Jun 2026
495events since 19506 deaths, 29 injuries recorded
15disaster declarationslast 26 Mar 2020
333NFIP flood claims$6.4M paid

Compared with Illinois and the United States

MeasureGrundy CountyIllinoisUS
Recorded events since 195049566,7221,977,440
Events per 100 square miles118.4120.256.0
Events per 10,000 residents93.452.759.6
Events in the last 12 months323,23262,008
Deaths recorded by NCEI61,14826,435
Property damage (NCEI estimates)$96M$6.9B$575B
NFIP claims per 1,000 residents6.34.28.1
Average paid NFIP claim$23K$14K$43K
Claims per 100 policies in force, last 10 years31.721.116.1

County-recorded events plus zone-recorded events whose forecast zone is named for the county. State and US rows include events recorded only by forecast zone. Rates use 2021 Census population and land area.

Events by decade

Tornado: 1
Tornado: 1Wind: 2
Tornado: 3Wind: 6
Hail: 2Tornado: 4Wind: 13
Hail: 18Flood: 4Wind: 31Winter: 4Cold: 1
Hail: 26Tornado: 1Flood: 20Wind: 59Winter: 15Heat: 1Cold: 6Drought: 9Wildfire: 1Lightning: 8Other: 4
Hail: 25Tornado: 9Flood: 12Wind: 44Winter: 19Heat: 2Cold: 8Lightning: 1Other: 1
Hail: 4Tornado: 4Flood: 7Wind: 61Winter: 30Heat: 9Cold: 8Drought: 4Other: 7
11950s31960s91970s191980s581990s1502000s1212010s1342020s
Recorded events in Grundy County by decade and hazard group. HailTornadoFloodWindWinterHeatColdDroughtWildfireLightningOther NCEI recorded only tornadoes, hail and thunderstorm wind before 1996.

Trend: 318 events in the 20 years to 2025 against 139 in the 20 years before. Reporting practice changed in 1996 and again with automated reports in the 2000s, so decade totals measure the record as much as the weather.

Events by type

Wind216
Hail75
Winter68
Flood43
Tornado23
Cold23
Drought13
Heat12
Other12
Lightning9
Wildfire1
HazardEventsDeathsShare of state's events
■ Wind216—0.9%detail
■ Hail75—0.6%detail
■ Winter68—0.8%detail
■ Flood43—0.7%detail
■ Tornado23—0.6%detail
■ Cold2350.9%
■ Drought13—0.8%
■ Heat1210.4%
■ Other12—1.2%
■ Lightning9—2.0%
■ Wildfire1—4.5%

Hazard pages exist for hail, tornado, flood, wind and winter where the county has at least 10 recorded events. "Other" covers heavy rain, debris flow, dust, funnel clouds and similar reports.

Largest recorded events

DateEvent typeGroupMagnitudeProperty damageCrop damageDeathsInjuriesGeography
3 Feb 2007Extreme Cold/Wind ChillCold———1—Forecast zone
7 Feb 2008Cold/Wind ChillCold———1—Forecast zone
22 Jun 2009Excessive HeatHeat———1—Forecast zone
13 Dec 2010Cold/Wind ChillCold———1—Forecast zone
1 Jan 2010Cold/Wind ChillCold———1—Forecast zone
14 Jan 2024Extreme Cold/Wind ChillCold———1—Forecast zone
14 Feb 2015Winter WeatherWinter—$300K——12Forecast zone
22 Jun 2015TornadoTornadoEF3$25M——7County
17 Nov 2013TornadoTornadoEF2$11M——5County
12 Nov 1965TornadoTornadoF2$25M———County
31 May 2000Thunderstorm WindWind75 mph$100K——2County
17 Jul 1996Flash FloodFlood—$1.0M$16M——County
18 Apr 2013Flash FloodFlood—$15M———County
20 May 1975TornadoTornadoF2$250K——1County
24 Aug 1998High WindWind51 mph———1Forecast zone
23 May 2020TornadoTornadoEF0———1County
14 Sep 2008Flash FloodFlood—$5.0M$4.0M——County
15 Sep 2008FloodFlood—$3.0M———County
24 Aug 2007FloodFlood—$2.1M$500K——County
7 Jul 2003Thunderstorm WindWind70 mph$2.5M———County

Ranked by deaths, then injuries, then NCEI's damage estimate. Deaths and injuries are NCEI counts (direct plus indirect); no personal details are recorded here.

Federal disaster declarations

DeclaredNumberTypeIncidentTitlePrograms
26 Mar 2020DR-4489Major disasterBiologicalCovid-19 PandemicIndividual assistance, Public assistance
13 Mar 2020EM-3435EmergencyBiologicalCovid-19Public assistance
26 Nov 2013DR-4157Major disasterTornadoSevere Storms, Straight-Line Winds, And TornadoesIndividual assistance
10 May 2013DR-4116Major disasterFloodSevere Storms, Straight-Line Winds, And FloodingIndividual assistance, Public assistance
17 Mar 2011DR-1960Major disasterSnowstormSevere Winter Storm And SnowstormPublic assistance
3 Oct 2008DR-1800Major disasterSevere StormSevere Storms And FloodingIndividual assistance, Public assistance
25 Sep 2007DR-1729Major disasterSevere StormSevere Storms And FloodingIndividual assistance
7 Sep 2005EM-3230EmergencyHurricaneHurricane Katrina EvacuationPublic assistance
17 Jan 2001EM-3161EmergencySnowstormIllinois Winter Snow StormsPublic assistance
8 Jan 1999EM-3134EmergencySnowstormIl-Winter Storm 1/1/99Public assistance
25 Jul 1996DR-1129Major disasterSevere StormSevere Storms And FloodingIndividual assistance, Public assistance
29 Mar 1985DR-735Major disasterFloodSevere Storms & FloodingIndividual assistance
16 Jan 1979EM-3068EmergencySnowstormBlizzards & SnowstormsPublic assistance
10 Jun 1974DR-438Major disasterFloodSevere Storms & FloodingIndividual assistance, Public assistance
4 Sep 1972DR-351Major disasterFloodSevere Storms & FloodingIndividual assistance, Public assistance

Declarations in which FEMA designated this county, from the OpenFEMA Disaster Declarations Summaries (v2). DR: major disaster; EM: emergency; FM: fire management assistance. Programs show whether individual or public assistance was made available.

Flood insurance claims

197820022026
NFIP claims by year of loss in Grundy County, 1978 to 2026 (hover for the amount paid).
Claims since 1978333
Paid claims282
Total paid$6.4M
Average paid claim$23K
Repetitive-loss properties425 severe
Residential policies in force1610.8% of 20,506 structures
Year of lossClaimsPaid claimsAmount paidAverage paid
202411$3,047$3,047
202310$0—
20202727$1,034,125$38,301
20191110$228,400$22,840
2018109$254,069$28,230
201711$18,094$18,094
201611$35,155$35,155
2015169$100,113$11,124
201421$11,157$11,157
20136155$2,078,874$37,798
201222$19,301$9,651
201110$0—
200943$33,685$11,228
20084440$1,250,780$31,269
200786$53,317$8,886
200611$6,558$6,558
200411$1,279$1,279
200122$21,684$10,842
200010$0—
199893$12,927$4,309
199765$26,772$5,354
199675$148,917$29,783
199510$0—
199332$21,210$10,605
199210$0—

OpenFEMA NFIP claims (v3, as of 8 Sep 2026), aggregated by year of loss; amounts are building, contents and increased-cost-of-compliance payments as recorded. Repetitive-loss counts from the NFIP Multiple Loss Properties file (2 Aug 2026); policies in force from the NFIP Residential Penetration Rates file (3 Aug 2026).

National Risk Index

Overall riskRelatively Lowscore 66.5 of 100
Expected annual loss$50MRelatively Low
Social vulnerabilityVery Low
Community resilienceVery High
Hazard (NRI)Risk ratingExpected annual loss
Inland floodingRelatively Low$22,176,238
Cold waveRelatively High$19,929,274
TornadoRelatively Moderate$4,726,398
Strong windRelatively Moderate$1,553,304
EarthquakeVery Low$754,517
Heat waveRelatively Low$592,117
LightningVery Low$122,453
DroughtRelatively Low$101,326
HailVery Low$76,227
Winter weatherRelatively Low$47,083
Ice stormVery Low$45,531
WildfireVery Low$10,549
HurricaneVery Low$3,285
LandslideVery Low$817

FEMA National Risk Index, December 2025 release. Ratings are FEMA's relative comparison of counties; expected annual loss is FEMA's modelled estimate of average yearly building, population and agriculture loss. See how to read the NRI.

Hurricane and tropical storm passes

Tracks within 100 miles3
Tracks within 50 miles0
Hurricane strength within 50 miles0
StormYearClosest approachMax wind while within 100 mi
Ike200893 mi58 mph
Unnamed Atlantic storm193269 mi40 mph
Unnamed Atlantic storm190091 mi58 mph

HURDAT2 best-track positions at tropical-storm strength (34 kt) or more, measured from the county's Census centre point; through the 2025 season. Distance from a track is not the same as the extent of the storm's wind, rain or surge.

ZIP codes with flood claims

ZIP codes whose NFIP claims carry this county's code, with the number of claims. Five or more claims are needed for a ZIP page to be indexed.

Questions and answers

How often does it hail in Grundy County, IL?

NCEI records 75 hail events in Grundy County since 1950, in 26 different years; that is about 1.0 recorded events a year. 13 reports were golf-ball size (1.75 in) or larger.

Has Grundy County had a tornado?

Yes. NCEI records 23 tornadoes in Grundy County since 1950, 7 of them rated (E)F2 or stronger. Tornado deaths recorded: 0.

When was the last federal disaster declaration for Grundy County?

26 Mar 2020: Covid-19 Pandemic, a major disaster declaration for biological. The county appears in 15 declarations since 1953.

How many flood insurance claims have been filed in Grundy County, and how much was paid?

333 NFIP claims since 1978, 282 of them paid, for $6.4M in total. FEMA publishes these figures redacted and aggregated; individual properties are not identified.

Is Grundy County in the National Risk Index's high-risk band?

FEMA's National Risk Index (December 2025) rates the county "Relatively Low" for overall risk, "Relatively Low" for expected annual loss, "Very Low" for social vulnerability and "Very High" for community resilience. These ratings are FEMA's relative comparison across all US counties.

How does Grundy County compare with the rest of Illinois?

118.4 recorded events per 100 square miles against 120.2 statewide, and 6.3 NFIP claims per 1,000 residents against 4.2. The comparison table on this page shows each measure beside the state and national figures.

Provenance

Storm events: NOAA NCEI Storm Events Database, yearly details files through 30 Jun 2026 (public domain). Declarations: OpenFEMA DisasterDeclarationsSummaries v2, refreshed 1 Oct 2026. Flood claims: OpenFEMA NfipClaims v3 as of 8 Sep 2026; NfipMultipleLossProperties v1 (2 Aug 2026); NfipResidentialPenetrationRates v1 (3 Aug 2026). Risk index: FEMA National Risk Index, December 2025. Hurricane tracks: NHC HURDAT2 through 2025. Population and area: US Census Bureau, 2021 vintage. Built 1 Oct 2026; see the methodology and corrections pages. Hazard hubs: Hail · Tornado · Flood · Wind · Winter.