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Mahaska County, Iowa severe weather history spans 428 recorded events between 1953 and 2025. The dominant hazard is thunderstorm wind, accounting for 35.3% of all recorded events. It ranks #1,140 nationally and #49 in Iowa.
428
Recorded events
1
Direct deaths
37
Direct injuries
$39.5M
Property damage
The record
What the Mahaska County, Iowa severe weather history record shows
Across the archive, Mahaska County, Iowa severe weather history averages 5.9 recorded events a year. The busiest stretch on record is the 2010s, with 165 events logged in that decade alone. Roughly 46 events fall before 1990 and 382 from 1990 onward — a gap that reflects the expansion of NOAA reporting practice as much as the weather itself.
The deadliest hazard in the Mahaska County, Iowa record is tornado, responsible for 1 direct deaths. The costliest is tornado, with $27.2M in reported property damage. In total, 8 distinct hazard types appear in this county archive, each listed with its own dated record below.
By hazard type
Every hazard type recorded in Mahaska County
| Hazard | Events | Deaths | Damage | Max | Span |
|---|---|---|---|---|---|
| Thunderstorm Wind | 151 | 0 | $2.4M | 87 | 1957–2025 |
| Hail | 91 | 0 | $978K | 4.75 | 1960–2024 |
| Flood | 78 | 0 | $5.3M | 0 | 1996–2019 |
| Heavy Rain | 39 | 0 | $0 | 0 | 2008–2022 |
| Flash Flood | 29 | 0 | $3.2M | 0 | 1996–2024 |
| Tornado | 27 | 1 | $27.2M | F4 | 1953–2018 |
| Lightning | 8 | 0 | $357K | 0 | 1996–2015 |
| Funnel Cloud | 5 | 0 | $0 | 0 | 1997–2019 |
Decade by decade
Mahaska County, Iowa severe weather history by decade
Reporting practice changed over time — early decades are undercounted, not calmer.
Tornado tracks
Paths crossing this county
31 mapped tornado paths intersect this county: 24 touched down inside it and 7 crossed in from a neighbouring county. This comes from path geometry, not county-tagged reports.
| Date | Scale | Deaths | Injuries | Path length | Origin |
|---|---|---|---|---|---|
| 1984-06-07 | EF4 | 3 | 64 | 134.0 mi | Crossed in |
| 2018-07-19 | EF3 | 0 | 13 | 9.2 mi | Crossed in |
| 2015-11-11 | EF2 | 0 | 0 | 6.6 mi | Touched down here |
| 2008-05-30 | EF2 | 0 | 10 | 19.2 mi | Crossed in |
| 2007-09-30 | EF2 | 0 | 0 | 21.9 mi | Crossed in |
| 1965-05-25 | EF2 | 0 | 0 | 2.0 mi | Touched down here |
| 1964-06-22 | EF2 | 0 | 0 | 6.4 mi | Crossed in |
| 1956-08-18 | EF2 | 0 | 0 | 11.5 mi | Touched down here |
| 1953-06-27 | EF2 | 0 | 1 | 7.8 mi | Touched down here |
| 2015-11-11 | EF1 | 0 | 0 | 24.6 mi | Touched down here |
Significant events
Deadliest events on record in Mahaska County
| Date | Type | Location | Deaths | Injuries | Damage |
|---|---|---|---|---|---|
| Jun 8, 1984 | Tornado | 1 | 30 | $25.0M | |
| May 11, 1985 | Tornado | 0 | 4 | $25K | |
| Aug 5, 1996 | Lightning | OSKALOOSA | 0 | 1 | $0 |
| Sep 17, 1978 | Tornado | 0 | 1 | $250K | |
| Jun 28, 1953 | Tornado | 0 | 1 | $3K |
From the record
What the reports say
Written by National Weather Service staff at the time of the event · public domain
Shingles were removed from the roof of a house. An outbuilding was damaged and the top of an outbuilding was crushed. Damage was done to structures on the west side of Oskaloosa from the storm after the tornado had lifted. Intermittent track with rain wrapped tornado and considerable RFD wind damage.
This tornado continued into Mahaska county from Marion county. The tornado path was initially east in Mahaska county but a satellite tornado moved south on the backside of the parent rotation and the interaction turned the main circulation back to the southeast remaining in that heading for the remainder of the path. The tornado did encounter one farmstead producing EF2 damage to the structures onsite before remaining in agricultural fields for the rest of its path.
Tornado started in rural Mahaska county south of Barnes City. Tornado damaged or destroyed several structures along its path. Also damaged several trees with branches and trunks snapped. In Barnes City, multiple outbuildings were slid off their foundation. The back end of one car was shifted by 2 ft. Tornado then moved into Poweshiek county before dissipating.
Context
Risk, population and federal disasters
Very Low
FEMA NRI risk rating
22,021
Population (ACS)
$158K
Median home value
20
Federal declarations
| Declared | Incident | Title | Type |
|---|---|---|---|
| Mar 23, 2020 | Biological | COVID-19 PANDEMIC | DR |
| Mar 13, 2020 | Biological | COVID-19 | EM |
| Mar 23, 2019 | Flood | SEVERE STORMS AND FLOODING | DR |
| Aug 5, 2014 | Severe Storm | SEVERE STORMS, TORNADOES, STRAIGHT-LINE WINDS, AND FLOODING | DR |
| Jul 2, 2013 | Severe Storm | SEVERE STORMS, TORNADOES, AND FLOODING | DR |
| Jul 29, 2010 | Severe Storm | SEVERE STORMS, FLOODING, AND TORNADOES | DR |
Within the county
Most affected places
- Oskaloosa 157
Quick answers
Frequently asked
How many severe weather events have been recorded in Mahaska County, Iowa?
428 events are on record between 1953 and 2025, causing 1 direct deaths and $39.5M in property damage.
What is the most common severe weather hazard in Mahaska County?
Thunderstorm Wind, with 151 recorded events — 35.3% of everything in the archive for this county.
How many tornadoes have crossed Mahaska County?
31 mapped tornado paths intersect the county boundary; 24 of them touched down inside it. This is derived from path geometry, not county-tagged reports.
How many federal disaster declarations cover Mahaska County?
20 federal disaster declarations from FEMA include Mahaska County, each tied to a specific incident period.
How risky is Mahaska County compared with the rest of the country?
FEMA's National Risk Index rates Mahaska County as very low risk, placing it in the 30 percentile of its state for expected annual loss.
Where does the Mahaska County, Iowa severe weather history data come from?
Every figure is drawn from United States federal public-domain records: NOAA/NCEI Storm Events for the event archive, NOAA SPC SVRGIS for mapped tornado paths, FEMA for disaster declarations and risk ratings, and the U.S. Census for population context. Dates are shown in UTC and recent entries may still be revised by NOAA.
Nearby
Neighbouring counties
- Madison County 402
- Marion County 710
- Lyon County 436
- Marshall County 528
- Lucas County 296
- Mills County 329
Cite this page
“Mahaska County, Iowa.” Severe Weather History. severeweatherhistory.com/county/iowa/mahaska-county/ · Data: NOAA/NCEI, FEMA, U.S. Census — public domain.