Hail history for Lake Koshkonong, Wisconsin
NOAA hail reports in and within about 5 km (3 miles) of Lake Koshkonong since 2000, with preliminary reports to November 3, 2026.
Readout · Lake Koshkonong
- Last hail
- Apr 18, 2025
- 1.25 in, half dollar size
- Hail days, last 5 years
- 2
- since Nov 3, 2021 · 7 reports
- Largest ever
- 2.00 in
- hen egg · Apr 18, 2025
15 reports on 9 days since 2000 · #133 of 271 Wisconsin places
Hail map · Lake Koshkonong
- Under 1 in
- 1–1.75 in
- 1.75–2.5 in
- 2.5–4 in
- 4 in +
- No size
For homeowners
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Send a request to Moxisync Labs for review. The latest hail report in Lake Koshkonong is from April 18, 2025. We’re building local roofer coverage. Submitting a request does not guarantee a quote or book an inspection.
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What the record says about Lake Koshkonong
The latest hail report in and around Lake Koshkonong is from April 18, 2025, 1.25 in (half dollar size). Since November 3, 2021 there have been 2 separate hail days; the biggest stones in that time were 2.00 in on April 18, 2025.
Over the 20 years 2006–2025, Lake Koshkonong logged 12 reports on 6 hail days, about 0.6 reports a year. That is 33% more than the median Wisconsin town on this site (0.5 a year) and ranks #133 of 271 Wisconsin cities and towns on this site for all-time reports. Lake Koshkonong accounts for 9% of the 174 reports filed in Rock County.
7% of reports with a size were 2 inches (hen egg) or larger, against 6% for the median Wisconsin town on this site. The largest hail on record here is 2.00 in (hen egg) on April 18, 2025 near 0.86 NE Mallwood.
Reports were up 40% in 2016–2025 (7) compared with 2006–2015 (5). The busiest year was 2025, with 4 reports on 1 day. Hail here peaks in July (33% of reports); 53% fall between April and June.
Reports a year 2006–2025 average
- Lake Koshkonong 0.6
- Rock County 5.0
- Median Wisconsin town on this site 0.5
Hail days 2006–2025
- Lake Koshkonong 6
- Rock County 56
- Median Wisconsin town on this site 7
Share 2 in or larger of sized reports
- Lake Koshkonong 7%
- Rock County 9%
- Median Wisconsin 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 | 4 | 4 | |||||||||||
| 2024 | 0 | ||||||||||||
| 2023 | 0 | ||||||||||||
| 2022 | 3 | 3 | |||||||||||
| 2021 | 0 | ||||||||||||
| 2020 | 0 | ||||||||||||
| 2019 | 0 | ||||||||||||
| 2018 | 0 | ||||||||||||
| 2017 | 0 |
Hail days since Nov 3, 2021
| Date | Reports | Largest | Storm page |
|---|---|---|---|
| Apr 18, 2025 | 4 | 2.00 in | — |
| Jul 23, 2022 | 3 | 1.75 in | — |
Largest hail on record
| Date | Size | Location | County | Time · source |
|---|---|---|---|---|
| Apr 18, 2025 | 2.00 inhen egg | 0.86 NE Mallwood | Rock | 06:14 local · NCEI |
| Apr 18, 2025 | 1.75 ingolf ball | Busseyville | Jefferson | 06:15 local · NCEI |
| Apr 18, 2025 | 1.75 ingolf ball | 1.01 E Mallwood | Rock | 06:11 local · NCEI |
| Jul 23, 2022 | 1.75 ingolf ball | 1.23 NE Mallwood | Rock | 18:51 local · NCEI |
| Jun 21, 2010 | 1.50 inping pong ball | 2 E Albion | Dane | 19:19 local · NCEI |
Size of every report
- Under 1 in 3 20%
- 1–2 in 11 73%
- 2 in + 1 7%
Most recent reports
| Date | Size | Location | County | Time · source |
|---|---|---|---|---|
| Apr 18, 2025 | 1.25 inhalf dollar | 2.94 SSW Ft Atkinson | Jefferson | 06:27 local · NCEI |
| Apr 18, 2025 | 1.75 ingolf ball | Busseyville | Jefferson | 06:15 local · NCEI |
| Apr 18, 2025 | 2.00 inhen egg | 0.86 NE Mallwood | Rock | 06:14 local · NCEI |
| Apr 18, 2025 | 1.75 ingolf ball | 1.01 E Mallwood | Rock | 06:11 local · NCEI |
| Jul 23, 2022 | 1.00 inquarter | 1.01 W Charlie Bluff | Rock | 19:00 local · NCEI |
| Jul 23, 2022 | 1.25 inhalf dollar | Mallwood | Rock | 18:55 local · NCEI |
| Jul 23, 2022 | 1.75 ingolf ball | 1.23 NE Mallwood | Rock | 18:51 local · NCEI |
| Jun 21, 2010 | 1.50 inping pong ball | 2 E Albion | Dane | 19:19 local · NCEI |
| Jun 21, 2010 | 1.50 inping pong ball | 2 E Newville | Rock | 19:15 local · NCEI |
| Jul 9, 2007 | 1.00 inquarter | 5 NE Milton | Rock | 12:00 local · NCEI |
| Mar 21, 2007 | 0.75 inpenny | Busseyville | Jefferson | 17:58 local · NCEI |
| Aug 25, 2006 | 0.75 inpenny | Newville | Rock | 10:42 local · NCEI |
Hail history near Lake Koshkonong
- Fort Atkinson 10 km · 20
- Milton 10 km · 13
- Edgerton 11 km · 27
- Whitewater 17 km · 17
- Jefferson 19 km · 13
- Janesville 20 km · 48
- Lake Mills 24 km · 28
- Stoughton 24 km · 20
Questions about hail in Lake Koshkonong
How often does it hail in Lake Koshkonong, Wisconsin?
15 hail reports have been logged in and within about 5 km (3 miles) of Lake Koshkonong since 2000. Over the 20 years 2006–2025 that averages 0.6 reports a year. That ranks #133 of 271 Wisconsin places by number of reports.
When is hail season in Lake Koshkonong?
Most reports come in July, April, May. July alone accounts for 33% of all reports.
What is the largest hail recorded in Lake Koshkonong?
2.00 in (hen egg size) on April 18, 2025 near 0.86 NE Mallwood. 7% of reports here were 2 inches or larger.
When did it last hail in Lake Koshkonong?
The most recent report in this data is from April 18, 2025 (1.25 in). Final NOAA data runs to July 31, 2026; preliminary NWS reports run to November 3, 2026.
How many hail storms has Lake Koshkonong had in the last five years?
2 separate days with hail reports since November 3, 2021, adding up to 7 reports. The most recent was April 18, 2025.
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.