Hail history for Thornton, Iowa
NOAA hail reports in and within about 5 km (3 miles) of Thornton since 1991, with preliminary reports to November 3, 2026.
Readout · Thornton
- Last hail
- Aug 11, 2023
- 1.00 in, quarter size
- Hail days, last 5 years
- 1
- since Nov 3, 2021 · 1 report
- Largest ever
- 1.75 in
- golf ball · May 10, 2003
13 reports on 10 days since 1991 · #339 of 483 Iowa places
Hail map · Thornton
- Under 1 in
- 1–1.75 in
- 1.75–2.5 in
- 2.5–4 in
- 4 in +
- No size
For homeowners
Roof damage after hail? Get a free inspection
Hail bruises shingles and cracks seals in ways you can't see from the ground, and most insurers set a claim deadline after the storm. The latest hail report in Thornton is from August 11, 2023. A local roofer can check and document it at no cost.
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What the record says about Thornton
The latest hail report in and around Thornton is from August 11, 2023, 1.00 in (quarter size). Since November 3, 2021 there has been one hail day; the biggest stones in that time were 1.00 in on August 11, 2023.
Over the 20 years 2006–2025, Thornton logged 7 reports on 6 hail days, about 0.3 reports a year. That is 22% less than the median Iowa town on this site (0.5 a year) and ranks #339 of 483 Iowa cities and towns on this site for all-time reports. Thornton accounts for 7% of the 184 reports filed in Cerro Gordo County.
0% of reports with a size were 2 inches (hen egg) or larger, against 6% for the median Iowa town on this site. The largest hail on record here is 1.75 in (golf ball) on May 10, 2003 near Thornton.
The busiest year was 2013, with 4 reports on 3 days. Hail here peaks in May (31% of reports); 62% fall between April and June.
Reports a year 2006–2025 average
- Thornton 0.3
- Cerro Gordo County 5.1
- Median Iowa town on this site 0.5
Hail days 2006–2025
- Thornton 6
- Cerro Gordo County 47
- Median Iowa town on this site 7
Share 2 in or larger of sized reports
- Thornton 0%
- Cerro Gordo County 2%
- Median Iowa town on this site 6%
Hail over time
| Year | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Total |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2026 | 0 | ||||||||||||
| 2025 | 0 | ||||||||||||
| 2024 | 0 | ||||||||||||
| 2023 | 1 | 1 | |||||||||||
| 2022 | 0 | ||||||||||||
| 2021 | 0 | ||||||||||||
| 2020 | 0 | ||||||||||||
| 2019 | 0 | ||||||||||||
| 2018 | 0 | ||||||||||||
| 2017 | 1 | 1 |
Hail days since Nov 3, 2021
| Date | Reports | Largest | Storm page |
|---|---|---|---|
| Aug 11, 2023 | 1 | 1.00 in | — |
Largest hail on record
| Date | Size | Location | County | Damage | Time · source |
|---|---|---|---|---|---|
| May 10, 2003 | 1.75 ingolf ball | Thornton | Cerro Gordo | $15K | 14:54 local · NCEI |
| Jun 19, 2002 | 1.50 inping pong ball | Thornton | Cerro Gordo | $15K | 02:15 local · NCEI |
| Jul 22, 2013 | 1.25 inhalf dollar | 1.22 SW Hurley | Cerro Gordo | $5K | 15:59 local · NCEI |
| Aug 11, 2023 | 1.00 inquarter | Thornton | Cerro Gordo | — | 20:21 local · NCEI |
| May 15, 2017 | 1.00 inquarter | 1.22 NE Thornton | Cerro Gordo | — | 16:44 local · NCEI |
Size of every report
- Under 1 in 4 31%
- 1–2 in 9 69%
- 2 in + 0 0%
Most recent reports
| Date | Size | Location | County | Damage | Time · source |
|---|---|---|---|---|---|
| Aug 11, 2023 | 1.00 inquarter | Thornton | Cerro Gordo | — | 20:21 local · NCEI |
| May 15, 2017 | 1.00 inquarter | 1.22 NE Thornton | Cerro Gordo | — | 16:44 local · NCEI |
| Oct 4, 2013 | 1.00 inquarter | 0.86 SW Thornton | Cerro Gordo | $3K | 17:14 local · NCEI |
| Jul 22, 2013 | 0.75 inpenny | 6.9 WNW Chapin | Franklin | — | 17:00 local · NCEI |
| Jul 22, 2013 | 1.25 inhalf dollar | 1.22 SW Hurley | Cerro Gordo | $5K | 15:59 local · NCEI |
| Jun 22, 2013 | 0.88 innickel | 0.86 SW Thornton | Cerro Gordo | — | 20:30 local · NCEI |
| Aug 4, 2008 | 0.88 innickel | 0.86 SW Thornton | Cerro Gordo | $2K | 07:47 local · NCEI |
| May 10, 2003 | 1.00 inquarter | 4 NW Thornton | Cerro Gordo | $5K | 15:11 local · NCEI |
| May 10, 2003 | 1.75 ingolf ball | Thornton | Cerro Gordo | $15K | 14:54 local · NCEI |
| Jun 19, 2002 | 1.00 inquarter | 1 E Thornton | Cerro Gordo | $5K | 02:30 local · NCEI |
| Jun 19, 2002 | 1.50 inping pong ball | Thornton | Cerro Gordo | $15K | 02:15 local · NCEI |
| May 16, 1992 | 1.00 inquarter | — | Cerro Gordo | — | 15:56 local · NCEI |
Hail history near Thornton
- Sheffield 16 km · 12
- Rockwell 17 km · 12
- Alexander 17 km · 10
- Latimer 20 km · 13
- Clear Lake 21 km · 33
- Belmond 21 km · 18
- Garner 25 km · 20
- Mason City 27 km · 71
Questions about hail in Thornton
How often does it hail in Thornton, Iowa?
13 hail reports have been logged in and within about 5 km (3 miles) of Thornton since 1991. Over the 20 years 2006–2025 that averages 0.3 reports a year. That ranks #339 of 483 Iowa places by number of reports.
When is hail season in Thornton?
Most reports come in May, June, July. May alone accounts for 31% of all reports.
What is the largest hail recorded in Thornton?
1.75 in (golf ball size) on May 10, 2003 near Thornton. 0% of reports here were 2 inches or larger.
When did it last hail in Thornton?
The most recent report in this data is from August 11, 2023 (1.00 in). Final NOAA data runs to July 31, 2026; preliminary NWS reports run to November 3, 2026.
How many hail storms has Thornton had in the last five years?
1 separate days with hail reports since November 3, 2021, adding up to 1 reports. The most recent was August 11, 2023.
Where does this hail data come from?
Hail reports come from the NOAA NCEI Storm Events Database, which the National Weather Service compiles from spotter, public, law enforcement and media reports. Recent days use preliminary NWS Local Storm Reports via the Iowa Environmental Mesonet until NOAA publishes final data. Only reported hail is counted, so areas with fewer people tend to have fewer reports.