45
Recorded events
0
Direct deaths
3
Direct injuries
$5.3M
Property damage
Tornado in Mercer County, Illinois: 45 recorded events between 1952 and 2026. The strongest on record measured F3. That places the county #479 nationally and #24 statewide for this hazard.
Decade by decade
Tornado in Mercer County, Illinois: events per decade
Reporting practice changed over time — early decades are undercounted, not calmer.
The busiest decade for tornado in Mercer County is the 2000s, when 12 of the county's 45 recorded events were logged. Comparing decades is useful for spotting active periods, but the earliest years are thin because systematic reporting for this hazard began later.
Within the Mercer County archive, tornado makes up 13.2% of all recorded severe weather across 8 hazard types. Nationally the county sits at #479 for this hazard and #24 within Illinois, putting it in the 83.2 percentile of all U.S. counties.
Seasonality
Events by month
Apr is the peak month for tornado in Mercer County with 14 recorded events, while Jan is the quietest. Seasonality here is a property of the archive as much as the climate: reports cluster where population and spotter networks are densest.
Tornado tracks
Paths crossing this county
| Date | Scale | Path length | Max width | Origin |
|---|---|---|---|---|
| 1978-08-15 | EF3 | 6.4 mi | 77 yd | Touched down here |
| 1974-06-14 | EF3 | 48.6 mi | 440 yd | Crossed in |
| 2015-05-24 | EF2 | 6.8 mi | 50 yd | Touched down here |
| 2006-04-13 | EF2 | 2.0 mi | 50 yd | Touched down here |
| 1998-06-18 | EF2 | 6.0 mi | 880 yd | Touched down here |
| 1974-04-13 | EF2 | 0.1 mi | 20 yd | Touched down here |
| 1973-04-21 | EF2 | 30.2 mi | 10 yd | Touched down here |
| 2025-06-03 | EF1 | 1.6 mi | 175 yd | Touched down here |
| 2025-06-03 | EF1 | 10.8 mi | 250 yd | Touched down here |
| 2025-06-03 | EF1 | 3.8 mi | 100 yd | Touched down here |
Significant events
Deadliest on record
| Date | Location | Scale | Deaths | Injuries | Damage |
|---|---|---|---|---|---|
| Jun 14, 1974 | F3 | 0 | 1 | $0 | |
| Apr 14, 1974 | F2 | 0 | 1 | $3K | |
| Apr 24, 1965 | F1 | 0 | 1 | $250K |
Most recent
Latest recorded events
| Date | Location | Magnitude | Damage |
|---|---|---|---|
| Apr 17, 2026 | VIOLA | EF0 | $0 |
| Jun 3, 2025 | HAMLET | EF1 | $0 |
| Jun 3, 2025 | MANNON | EF1 | $0 |
| Jun 3, 2025 | NEW BOSTON | EF1 | $0 |
| Apr 21, 2025 | NEW BOSTON | EF0 | $0 |
| Jul 16, 2024 | PREEMPTION | EF1 | $0 |
| Aug 20, 2022 | ALEDO | EFU | $0 |
| Aug 20, 2022 | MANNON | EFU | $0 |
| Nov 10, 2020 | BURGESS | EF1 | $0 |
| Nov 10, 2020 | JOY | EF1 | $0 |
Other hazards here
More from Mercer County
- Thunderstorm Wind 135
- Hail 96
From the record
What the reports say
Written by National Weather Service staff at the time of the event · public domain
The tornado damaged several rural home sites. Northeast of Seaton damage was noted to farm buildings and a silo. South of Aledo seven power lines poles were snapped, and a farmhouse 4 miles west of Aledo was destroyed. The tornado also damaged or destroyed farm buildings, roofs and chimneys south of Aledo.
Official NWS storm survey team found that the tornado moved northeast with peak winds around 115 mph. It damaged mainly trees and outbuildings along its path. The worst damage was near the beginning of the path, where a large machine shed was completely destroyed, 2 garages were destroyed, and a house partially un-roofed. Witnesses described a blinding rain accompanied the tornado.
Tornado was rated a higher end EF-1 with peak winds 105 mph, a path length of 5.73 miles with a max path width of 150 yards. This higher end EF-1 tornado caused damage to numerous farm outbuildings, a few homes and trees across Mercer and Henry counties. One house partially lost a roof while another was impelled by flying debris. Approximately 30 to 40 trees were snapped at the trunks, a couple of dozen were uprooted, with about 50 trees experiencing limb damage. This tornado continued into Henry county.
Quick answers
Frequently asked
How many tornado events are on record in Mercer County, Illinois?
45 tornado events are recorded in Mercer County between 1952 and 2026, causing 0 direct deaths.
What is the strongest tornado recorded in Mercer County?
The strongest tornado on record in Mercer County measured F3.
Where does the tornado data for Mercer County come from?
All events come from the NOAA/NCEI Storm Events Database, the federal public-domain archive of severe weather reports. Dates are UTC, damage is as reported and not inflation-adjusted, and the most recent entries may still be revised.
Cite this page
“Tornado in Mercer County, Illinois.” Severe Weather History. severeweatherhistory.com/county/illinois/mercer-county/tornado/ · Data: NOAA/NCEI, FEMA, U.S. Census — public domain.