Frost history / Riggins, ID
Riggins, ID: frost dates by year
Last spring and first fall frost at NOAA station USC00107706, 1951 to 2025, measured from daily minimum temperatures.
Elevation 2,056 ft, 45.354, -116.395. Download the data (JSON), NOAA daily records
Summary at 32°F
| Last spring frost | First fall frost | |
|---|---|---|
| Median | Apr 23 | Oct 21 |
| Earliest | Mar 11 (1993) | Sep 15 (1970) |
| Latest | May 31 (1955) | Nov 21 (1992) |
| Trend | 0.5 days later per decade | 1.2 days earlier per decade |
| Years with data | 54 | 52 |
At 28°F (hard freeze) the median last spring date is Mar 31 and the median first fall date is Nov 2.
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 | Oct 21 | Apr 23 | Oct 28 |
| 2024 | May 24 | Oct 19 | May 4 | Oct 29 |
| 2023 | May 10 | Oct 24 | Apr 19 | Oct 28 |
| 2022 | May 22 | Oct 24 | May 11 | Oct 24 |
| 2021 | May 11 | Oct 12 | Apr 21 | Nov 8 |
| 2020 | May 7 | Sep 27 | Apr 17 | Oct 13 |
| 2019 | May 3 | Oct 2 | May 1 | Oct 10 |
| 2018 | Apr 24 | Sep 28 | Apr 18 | Oct 12 |
| 2010 | Apr 11 | no data | Mar 14 | no data |
| 2009 | Apr 25 | Oct 10 | Mar 14 | Oct 10 |
| 2008 | Apr 26 | Oct 9 | Mar 31 | Nov 23 |
| 2007 | Apr 18 | Oct 27 | Apr 4 | Nov 22 |
| 2006 | Mar 27 | Oct 31 | Mar 13 | Oct 31 |
| 1999 | May 9 | Oct 16 | Apr 12 | Oct 17 |
| 1998 | Mar 31 | Oct 17 | Mar 31 | Oct 30 |
| 1997 | Apr 13 | Oct 12 | Apr 12 | Nov 11 |
| 1996 | Apr 21 | Oct 17 | Mar 25 | Oct 21 |
| 1995 | Apr 18 | Oct 30 | Mar 29 | Oct 31 |
| 1994 | Mar 27 | Oct 30 | Mar 26 | Nov 8 |
| 1993 | Mar 11 | Oct 26 | Mar 11 | Nov 7 |
| 1992 | Apr 7 | Nov 21 | Feb 5 | Nov 24 |
| 1991 | no data | Oct 29 | no data | Oct 30 |
| 1990 | Mar 30 | Oct 7 | Feb 19 | Dec 19 |
| 1989 | Apr 9 | no data | Mar 15 | no data |
| 1988 | May 2 | Oct 27 | Mar 31 | Nov 15 |
| 1987 | Apr 22 | Oct 13 | Mar 29 | Nov 15 |
| 1986 | Apr 30 | Oct 11 | Feb 20 | Nov 10 |
| 1985 | May 12 | Oct 8 | Mar 26 | Oct 9 |
| 1981 | Apr 14 | Oct 21 | Feb 11 | Nov 27 |
| 1979 | Apr 11 | no data | Mar 10 | no data |
| 1978 | Mar 16 | Oct 22 | Mar 15 | Oct 31 |
| 1977 | Apr 18 | Nov 3 | Mar 16 | Nov 9 |
| 1976 | Apr 25 | Oct 18 | Apr 24 | Nov 20 |
| 1975 | Apr 28 | no data | Apr 1 | no data |
| 1974 | May 16 | Oct 4 | Mar 23 | Oct 6 |
| 1973 | Apr 18 | Oct 3 | Apr 1 | Nov 3 |
| 1972 | Apr 30 | Oct 26 | Apr 26 | Oct 31 |
| 1971 | Apr 1 | Oct 15 | Apr 1 | Oct 28 |
| 1970 | Apr 18 | Sep 15 | Mar 31 | Oct 27 |
| 1969 | Mar 25 | Oct 6 | Mar 24 | Oct 13 |
| 1968 | Apr 24 | Nov 5 | Apr 23 | Dec 13 |
| 1967 | May 11 | Oct 24 | Mar 30 | Oct 24 |
| 1966 | Apr 19 | Oct 14 | Mar 23 | Nov 9 |
| 1965 | Apr 11 | Sep 17 | Mar 26 | Nov 29 |
| 1964 | May 23 | Nov 13 | Apr 18 | Nov 15 |
| 1963 | Apr 18 | Oct 26 | Apr 16 | Oct 27 |
| 1962 | no data | Nov 17 | no data | Dec 23 |
| 1961 | Apr 20 | Oct 30 | Apr 6 | Nov 2 |
| 1960 | no data | Oct 30 | no data | Nov 28 |
| 1959 | May 3 | Oct 1 | Apr 9 | Nov 5 |
| 1958 | Apr 29 | Oct 21 | Mar 13 | Nov 15 |
| 1957 | Apr 27 | Oct 20 | Apr 18 | Nov 3 |
| 1956 | no data | Oct 21 | no data | Oct 28 |
| 1955 | May 31 | Nov 2 | Mar 27 | Nov 2 |
| 1954 | May 2 | no data | Mar 31 | no data |
| 1953 | Apr 28 | no data | Apr 2 | no data |
| 1952 | Apr 9 | Nov 2 | Apr 8 | Nov 22 |
| 1951 | Apr 21 | Oct 25 | Apr 21 | Oct 31 |
"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.