Hamilton County, Iowa severe weather history spans 438 recorded events between 1963 and 2025. The dominant hazard is hail, accounting for 34.0% of all recorded events. It ranks #1,106 nationally and #45 in Iowa.
438
Recorded events
2
Direct deaths
17
Direct injuries
$46.3M
Property damage
The record
What the Hamilton County, Iowa severe weather history record shows
Across the archive, Hamilton County, Iowa severe weather history averages 7.1 recorded events a year. The busiest stretch on record is the 2000s, with 160 events logged in that decade alone. Roughly 44 events fall before 1990 and 394 from 1990 onward — a gap that reflects the expansion of NOAA reporting practice as much as the weather itself.
The deadliest hazard in the Hamilton County, Iowa record is tornado, responsible for 1 direct deaths. The costliest is tornado, with $41.5M 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 Hamilton County
| Hazard | Events | Deaths | Damage | Max | Span |
|---|---|---|---|---|---|
| Hail | 149 | 0 | $792K | 2.75 | 1974–2024 |
| Thunderstorm Wind | 134 | 0 | $1.6M | 78 | 1969–2025 |
| Tornado | 56 | 1 | $41.5M | F4 | 1963–2024 |
| Heavy Rain | 34 | 0 | $0 | 0 | 2007–2024 |
| Flash Flood | 21 | 1 | $1.1M | 0 | 1996–2018 |
| Flood | 21 | 0 | $1.3M | 0 | 1998–2019 |
| Funnel Cloud | 19 | 0 | $0 | 0 | 1996–2021 |
| Lightning | 4 | 0 | $71K | 0 | 1997–2025 |
Decade by decade
Hamilton County, Iowa severe weather history by decade
Reporting practice changed over time — early decades are undercounted, not calmer.
Tornado tracks
Paths crossing this county
56 mapped tornado paths intersect this county: 46 touched down inside it and 10 crossed in from a neighbouring county. This comes from path geometry, not county-tagged reports.
| Date | Scale | Deaths | Injuries | Path length | Origin |
|---|---|---|---|---|---|
| 1989-05-24 | EF4 | 0 | 0 | 66.0 mi | Touched down here |
| 2005-11-12 | EF3 | 1 | 3 | 17.6 mi | Crossed in |
| 1953-05-20 | EF3 | 1 | 0 | 116.1 mi | Crossed in |
| 2021-12-15 | EF2 | 0 | 0 | 16.3 mi | Crossed in |
| 2021-12-15 | EF2 | 0 | 0 | 12.1 mi | Crossed in |
| 1991-05-17 | EF2 | 0 | 0 | 9.0 mi | Touched down here |
| 1990-03-13 | EF2 | 0 | 0 | 22.0 mi | Crossed in |
| 1979-06-28 | EF2 | 0 | 10 | 7.2 mi | Touched down here |
| 1979-06-28 | EF2 | 0 | 0 | 1.0 mi | Touched down here |
| 1974-06-22 | EF2 | 0 | 0 | 0.1 mi | Touched down here |
Significant events
Deadliest events on record in Hamilton County
| Date | Type | Location | Deaths | Injuries | Damage |
|---|---|---|---|---|---|
| Nov 12, 2005 | Tornado | STRATFORD | 1 | 3 | $11.7M |
| Jun 8, 2008 | Flash Flood | KAMRAR | 1 | 0 | $50K |
| Jun 29, 1979 | Tornado | 0 | 10 | $250K | |
| Apr 8, 1999 | Thunderstorm Wind | ELLSWORTH | 0 | 4 | $20K |
From the record
What the reports say
Written by National Weather Service staff at the time of the event · public domain
Local law enforcement reports trees and power lines down at several locations around Hamilton County with the bulk of the damage in the Webster City and Kamrar areas. Widespread power outages after the storm had only been partly restored by morning.
This tornado entered Hamilton County from Webster County just south of Stratford and passed just south and east of town. This produced tree damage and completely destroyed an outbuilding northeast of town. The tornado continued to produce damage northeast of Stratford to outbuildings and trees before entering the Boone River valley and dissipating south several miles south of Webster City.
This tornado entered Hamilton County from Webster County. The tornado produced damage to multiple large utility poles along several county roads to the south and east of Stratford. The tornado finally lifted northwest of Stanhope as it approached the Boone River valley.
Context
Risk, population and federal disasters
Relatively Low
FEMA NRI risk rating
14,886
Population (ACS)
$156K
Median home value
21
Federal declarations
| Declared | Incident | Title | Type |
|---|---|---|---|
| May 24, 2024 | Severe Storm | SEVERE STORMS, TORNADOES, AND FLOODING | DR |
| Feb 23, 2022 | Severe Storm | SEVERE STORMS, STRAIGHT-LINE WINDS, AND TORNADOES | DR |
| 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 20, 2018 | Severe Storm | SEVERE STORMS, TORNADOES, STRAIGHT-LINE WINDS, AND FLOODING | DR |
Quick answers
Frequently asked
How many severe weather events have been recorded in Hamilton County, Iowa?
438 events are on record between 1963 and 2025, causing 2 direct deaths and $46.3M in property damage.
What is the most common severe weather hazard in Hamilton County?
Hail, with 149 recorded events — 34.0% of everything in the archive for this county.
How many tornadoes have crossed Hamilton County?
56 mapped tornado paths intersect the county boundary; 46 of them touched down inside it. This is derived from path geometry, not county-tagged reports.
How many federal disaster declarations cover Hamilton County?
21 federal disaster declarations from FEMA include Hamilton County, each tied to a specific incident period.
How risky is Hamilton County compared with the rest of the country?
FEMA's National Risk Index rates Hamilton County as relatively low risk, placing it in the 43 percentile of its state for expected annual loss.
Where does the Hamilton 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
- Guthrie County 515
- Hancock County 318
- Grundy County 350
- Hardin County 469
- Greene County 335
- Harrison County 496
Cite this page
“Hamilton County, Iowa.” Severe Weather History. severeweatherhistory.com/county/iowa/hamilton-county/ · Data: NOAA/NCEI, FEMA, U.S. Census — public domain.