Hazard Mitigation Plan update · Section 4 draft · prepared October 3, 2026
Hamilton County, Illinois Hazard Profiles
Draft. Built from public National Weather Service storm records (NOAA Storm Events, 1981 to June 2026). Not an adopted plan and not reviewed by FEMA.
Hamilton County's plan, the Hamilton County 2021 Hazard Mitigation Plan, expired April 13, 2026 in FEMA's plan-status data, with no update recorded as in progress on October 3, 2026. This chapter drafts the hazard-profile section of the update from 359 storm reports for the county, every one traceable to a NOAA event ID.
At a glance
6 hazards appear in the federal storm record for Hamilton County. Winter storms are the most frequent; high wind accounts for the most recorded deaths and damage.
Hazard
Days with reports, 1996–2025
Years with at least one
Deaths*
Injuries*
Property damage entered*
Thunderstorm wind
51
25/30
0
0
$796K
Hail
34
19/30
0
0
$850K
Tornado
4
4/30
0
0
$8.6M
Flooding
47
22/30
0
0
$861K
Winter storms
117
29/30
0
0
$110K
High wind (no storm)
64
26/30
1
0
$116K
* All years on record (tornado, wind and hail from the 1980s; other hazards from 1996). Dollars are as entered, not adjusted for inflation.
How often, year by year
Days with at least one report, 1996 to 2025. Each panel has its own scale. Hover a bar for the year.
Thunderstorm wind51 days · 25 of 30 yearsHail34 days · 19 of 30 yearsFlooding47 days · 22 of 30 yearsTornado4 days · 4 of 30 yearsWinter storms117 days · 29 of 30 years
Show the numbers behind the charts
Year
Thunderstorm wind
Hail
Tornado
Flooding
Winter storms
High wind (no storm)
1996
3
2
1
3
3
2
1997
1
0
0
0
5
1
1998
0
1
0
1
2
1
1999
1
0
0
3
3
1
2000
0
0
0
2
3
1
2001
1
1
0
1
1
1
2002
1
6
0
0
3
1
2003
2
0
0
0
3
0
2004
3
1
0
4
5
0
2005
2
0
0
0
1
0
2006
4
4
0
3
4
3
2007
1
1
0
0
6
0
2008
3
1
0
1
5
5
2009
1
0
0
1
2
4
2010
1
1
0
0
8
1
2011
1
1
1
5
4
2
2012
1
4
0
0
4
1
2013
0
0
0
2
5
1
2014
2
2
0
2
4
3
2015
1
0
1
1
6
1
2016
5
1
0
3
5
3
2017
0
2
0
1
2
5
2018
2
1
0
3
5
4
2019
2
1
0
0
5
5
2020
1
0
1
1
0
2
2021
0
0
0
1
6
1
2022
2
1
0
1
7
2
2023
5
1
0
5
3
7
2024
4
2
0
1
3
2
2025
1
0
0
2
4
4
When in the year
Days with reports by month, 1996 to 2025. Darker means more days.
J
F
M
A
M
J
J
A
S
O
N
D
Thunderstorm wind
1
2
2
8
7
11
10
3
1
5
1
Hail
1
4
12
6
2
3
4
1
1
Tornado
1
2
1
Flooding
3
2
5
6
6
4
7
5
4
1
4
Winter storms
39
37
8
2
5
26
High wind (no storm)
8
13
15
7
3
2
8
8
Tornado tracks, 1982–2020
9 tornadoes. Lines run from touchdown to lift within the county; dots are tornadoes recorded at a single point. Hover a track for its date and rating.
F0/EF0F1/EF1F2/EF2F3 or strongerF5Unrated
County outline from the Census Bureau (simplified); community labels sit at the average location of reports naming them.
Hazard profiles
Each profile answers FEMA's questions for hazard identification: what it is, where, how bad (extent), what has happened, and how likely it is to happen again.
Tornado
Description
A violently rotating column of air in contact with the ground, rated after the fact on the Fujita scale (through January 2007) or the Enhanced Fujita scale, EF0 to EF5, by the damage it leaves.
Location
Countywide; tornado reports name 4 communities, most often Piopolis, Mc Leansboro and Flint.
Extent
The strongest on record is the F4 of June 2, 1990. Tornadoes rated F2/EF2 or stronger touched down on 4 separate days.
Previous occurrences
9 tornadoes on 9 days from 1982 to 2020. Weather Service survey, March 19, 2020: "The tornado started in extreme eastern Jefferson County. The tornado moved across the northwest side of Dahlgren in Hamilton County. Several homes sustained roofing or soffit damage. One home had about a quarter of its roof removed and tossed about 50 yards. A few barns were …"
Probability
At least one tornado in 4 of 30 years (13%) from 1996 to 2025.
Recorded losses
0 deaths, 0 injuries, $8.6M in property damage as entered by the Weather Service (9 of 9 reports carry a dollar figure).
Severe thunderstorm wind
Description
Straight-line winds from thunderstorms, including downbursts, measured or estimated at 58 mph (50 knots) or more.
Location
Countywide; reports name 17 communities, most often Mc Leansboro, Dahlgren and Dale.
Extent
The highest gust on record is 104 knots (120 mph), estimated near Walpole on April 19, 2011. 9 reports reached 65 knots (75 mph) or more.
Previous occurrences
69 reports on 62 days since 1981. April 19, 2011: "An intense macroburst struck southeast Hamilton County with winds up to 120 mph. The average path width was four miles. Numerous homes were damaged. Dozens of barns, sheds, and other structures were damaged or destroyed. Many hundreds of …"
Probability
Reports in 25 of 30 years (83%) from 1996 to 2025; about 1.7 damaging-wind days a year.
Recorded losses
0 deaths, 0 injuries, $796K in property damage as entered by the Weather Service (47 of 69 reports carry a dollar figure).
Hail
Description
Ice stones from thunderstorm updrafts; reported at 3/4 inch and larger in this record.
Location
Countywide; reports name 9 communities, most often Mc Leansboro, Dahlgren and Blairsville.
Extent
Largest: 1.75 inches near Mc Leansboro on August 6, 2019.
Previous occurrences
43 reports on 35 days since 1994.
Probability
Reports in 19 of 30 years (63%) from 1996 to 2025.
Recorded losses
0 deaths, 0 injuries, $850K in property damage as entered by the Weather Service (2 of 43 reports carry a dollar figure).
Flooding (river, flash and heavy rain)
Description
River flooding, and flash flooding when heavy rain overwhelms streets, ditches and small streams.
Location
Countywide; reports name 16 communities, most often Mc Leansboro, Dale and Dahlgren.
Extent
The costliest entry is March 18, 2008, at $340K in property damage.
Previous occurrences
52 flood, flash-flood and heavy-rain reports since 1996. August 4, 2025: "Floodwaters resulted in the closure of part of IL-142 near County Rd 975N. One hour rainfall rates peaked at around 2'' (radar estimated) in that area."
Probability
Reports in 22 of 30 years (73%) from 1996 to 2025.
Recorded losses
0 deaths, 0 injuries, $861K in property damage as entered by the Weather Service (18 of 52 reports carry a dollar figure).
Winter storms and ice
Description
Heavy snow, blizzards, ice storms, sleet and lesser winter weather, recorded by forecast zone rather than by point.
Location
Countywide (forecast-zone records).
Extent
Ice storms on 4 occasions. Zone records rarely give snow or ice totals; the full plan adds station data.
Previous occurrences
119 zone events from 1996 to 2026: 75 winter weather, 27 winter storm, 13 heavy snow, 4 ice storm.
Probability
Events in 29 of 30 years (97%) from 1996 to 2025.
Recorded losses
0 deaths, 0 injuries, $110K in property damage as entered by the Weather Service (2 of 119 reports carry a dollar figure).
High wind (not from thunderstorms)
Description
Strong winds from large storm systems rather than thunderstorms, recorded by forecast zone.
Location
Countywide (forecast-zone records).
Extent
Highest: 65 knots (75 mph).
Previous occurrences
65 zone events since 1996.
Probability
Events in 26 of 30 years (87%) from 1996 to 2025.
Recorded losses
1 death, 0 injuries, $116K in property damage as entered by the Weather Service (60 of 65 reports carry a dollar figure).
Not covered by this record
Extreme heat, extreme cold, drought, earthquake and dam failure are not in the storm archive this chapter draws on. The full chapter profiles them from NOAA climate records, the U.S. Drought Monitor, USGS shaking maps and the state dam inventory, and the planning team decides which belong in the plan.
Previous occurrences by community
FEMA asks for hazard history for each participating jurisdiction. These are the communities the Weather Service names most often as the nearest place to a report.
Nearest community named in the report
Thunderstorm wind
Hail
Flooding
Tornado
All
Mc Leansboro
23
26
15
1
65
Dahlgren
8
8
5
1
22
Dale
5
8
13
Broughton
4
1
2
7
Blairsville
2
2
4
Bell Prairie City
2
1
1
4
Mcleansboro
3
3
Piopolis
1
1
1
3
Aden
1
2
3
Rural Hill
1
1
1
3
Mc Leansboro Muni Ar
1
2
3
Feakeyville
3
3
Diamond City
2
1
3
Delafield
1
1
2
Hoodville
1
1
2
Flint
1
1
2
Garrison
1
1
2
Mccleansboro
1
1
What this draft covers, and what the full update adds
Covered here
Type, location and extent of each recorded hazard (FEMA review element B1).
Previous occurrences and probability of future events, countywide and by community (element B2).
Added in the full update
Vulnerability and impacts on people, buildings and critical facilities from county parcel and building data (element B3).
National Flood Insurance Program repetitive-loss properties from FEMA (element B4).
Planning-team meetings, public input, capability review, the mitigation strategy and adoption.
Data notes
Before 1996 the storm database records only tornado, thunderstorm wind and hail, so every rate on this page uses 1996–2025.
Recent reports rarely carry a damage estimate: 24 of 39 wind, hail, tornado and flood reports since 2019 do. A missing dollar figure means "not estimated," not "no damage."
Reports follow people. Towns with more spotters and roads show more reports.
Winter storm, high wind and some flood events are recorded by forecast zone, not by point.