Frost history / Hinsdale 4 Sw, MT
Hinsdale 4 Sw, MT: frost dates by year
Last spring and first fall frost at NOAA station USC00244180, 1971 to 2025, measured from daily minimum temperatures.
Elevation 2,805 ft, 48.348, -107.153. Download the data (JSON), NOAA daily records
Summary at 32°F
| Last spring frost | First fall frost | |
|---|---|---|
| Median | May 8 | Sep 21 |
| Earliest | Apr 20 (1978) | Sep 6 (1992) |
| Latest | Jun 2 (1998) | Oct 24 (2024) |
| Trend | 2.5 days later per decade | 2.7 days later per decade |
| Years with data | 33 | 30 |
At 28°F (hard freeze) the median last spring date is Apr 28 and the median first fall date is Oct 7.
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 | Apr 24 | no data | Apr 24 | no data |
| 2024 | no data | Oct 24 | no data | Oct 29 |
| 2023 | no data | Oct 4 | no data | Oct 4 |
| 2022 | May 23 | no data | Apr 28 | no data |
| 2021 | May 23 | Oct 11 | Apr 25 | Oct 22 |
| 2020 | May 11 | Sep 8 | May 11 | Oct 17 |
| 2019 | May 20 | no data | May 4 | no data |
| 2002 | May 23 | no data | May 23 | no data |
| 2000 | May 14 | Sep 21 | May 14 | Sep 22 |
| 1999 | May 12 | no data | Apr 16 | no data |
| 1998 | Jun 2 | no data | Apr 19 | no data |
| 1995 | May 24 | Sep 20 | May 13 | Sep 21 |
| 1994 | Apr 30 | Oct 3 | Apr 30 | Oct 23 |
| 1993 | Apr 25 | Sep 13 | Apr 20 | Oct 8 |
| 1992 | Apr 22 | Sep 6 | Apr 22 | Oct 14 |
| 1991 | May 5 | Sep 17 | May 5 | Sep 18 |
| 1990 | May 9 | Sep 29 | Apr 30 | Oct 7 |
| 1989 | May 5 | Sep 10 | Apr 30 | Sep 11 |
| 1988 | Apr 27 | Oct 3 | Apr 26 | Oct 4 |
| 1987 | May 20 | Oct 9 | Apr 11 | Oct 9 |
| 1986 | May 16 | Oct 11 | Apr 16 | Oct 12 |
| 1985 | Apr 22 | Sep 20 | Apr 21 | Sep 24 |
| 1984 | May 8 | Sep 23 | May 8 | Sep 23 |
| 1983 | May 13 | Sep 18 | May 12 | Sep 20 |
| 1982 | May 31 | Sep 13 | Apr 20 | Oct 19 |
| 1981 | May 9 | Sep 27 | Apr 14 | Oct 14 |
| 1980 | May 8 | Sep 16 | May 7 | Oct 24 |
| 1979 | May 11 | Oct 9 | May 2 | Oct 21 |
| 1978 | Apr 20 | Sep 20 | Apr 20 | Oct 6 |
| 1977 | Apr 21 | Oct 4 | Apr 21 | Oct 5 |
| 1976 | May 6 | Sep 27 | May 3 | Oct 5 |
| 1975 | May 1 | Sep 12 | Apr 19 | Oct 9 |
| 1974 | May 3 | Sep 13 | May 3 | Sep 29 |
| 1973 | May 1 | Sep 16 | Apr 22 | Oct 10 |
| 1972 | May 6 | Sep 21 | May 6 | Sep 21 |
| 1971 | no data | Sep 17 | no data | Oct 8 |
"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.