Frost history / Hillsboro 2SW, WI
Hillsboro 2SW, WI: frost dates by year
Last spring and first fall frost at NOAA station USC00473650, 2014 to 2025, measured from daily minimum temperatures.
Elevation 1,043 ft, 43.634, -90.379. Download the data (JSON), NOAA daily records
Summary at 32°F
| Last spring frost | First fall frost | |
|---|---|---|
| Median | May 18 | Oct 5 |
| Earliest | Apr 30 (2018) | Sep 13 (2014) |
| Latest | Jun 12 (2023) | Oct 17 (2021) |
| Trend | 9.2 days later per decade | 4.3 days later per decade |
| Years with data | 12 | 12 |
At 28°F (hard freeze) the median last spring date is May 6 and the median first fall date is Oct 12.
The trend is a straight-line fit through the years with a freeze. A positive spring trend means the last frost now comes later. Short or patchy records give noisy trends.
Chart
Last spring frost (32°F)
First fall frost (32°F)
Dots are single years. The gray line is the median, the green line the fitted trend.
Year by year
| Year | Last spring 32°F | First fall 32°F | Last spring 28°F | First fall 28°F |
|---|---|---|---|---|
| 2025 | May 24 | Oct 8 | May 9 | Oct 9 |
| 2024 | May 5 | Oct 7 | Apr 25 | Oct 7 |
| 2023 | Jun 12 | Sep 14 | May 26 | Oct 11 |
| 2022 | May 24 | Sep 28 | May 23 | Sep 29 |
| 2021 | May 30 | Oct 17 | May 29 | Oct 22 |
| 2020 | May 13 | Oct 2 | May 13 | Oct 2 |
| 2019 | May 13 | Oct 12 | Apr 29 | Oct 25 |
| 2018 | Apr 30 | Sep 29 | Apr 30 | Oct 13 |
| 2017 | May 8 | Oct 16 | May 3 | Oct 26 |
| 2016 | May 19 | Oct 8 | May 15 | Oct 21 |
| 2015 | May 22 | Sep 30 | Apr 30 | Oct 14 |
| 2014 | May 17 | Sep 13 | Apr 23 | Oct 10 |
"none" means the station recorded no freeze at that threshold in that half of the year. "no data" means more than 10% of the season's daily readings were missing. Years with no usable data are left out. See the methodology for the rules, and the ZIP lookup for 1991 to 2020 frost probabilities.