Frost history / Adel, MT
Adel, MT: frost dates by year
Last spring and first fall frost at NOAA station USC00240056, 2013 to 2025, measured from daily minimum temperatures.
Elevation 5,017 ft, 47.009, -111.674. Download the data (JSON), NOAA daily records
Summary at 32°F
| Last spring frost | First fall frost | |
|---|---|---|
| Median | Jun 13 | Sep 5 |
| Earliest | May 24 (2020) | Aug 23 (2015) |
| Latest | Jul 20 (2019) | Sep 28 (2019) |
| Trend | 12.7 days earlier per decade | 2.6 days later per decade |
| Years with data | 11 | 13 |
At 28°F (hard freeze) the median last spring date is May 12 and the median first fall date is Sep 28.
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 | Jun 4 | Sep 4 | Jun 3 | Oct 4 |
| 2024 | no data | Sep 20 | no data | Oct 2 |
| 2023 | Jun 21 | Sep 18 | Apr 22 | Oct 5 |
| 2022 | Jun 6 | Sep 8 | May 20 | Sep 9 |
| 2021 | May 29 | Aug 24 | May 28 | Sep 16 |
| 2020 | May 24 | Aug 30 | May 10 | Oct 14 |
| 2019 | Jul 20 | Sep 28 | May 5 | Sep 28 |
| 2018 | Jul 5 | Aug 28 | May 3 | Sep 30 |
| 2017 | Jun 23 | Sep 15 | May 19 | Sep 23 |
| 2016 | Jun 20 | Aug 25 | May 12 | Sep 13 |
| 2015 | Jun 13 | Aug 23 | May 11 | Sep 28 |
| 2014 | Jun 12 | Sep 5 | May 14 | Sep 11 |
| 2013 | no data | Sep 26 | no data | Sep 27 |
"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.