Frost history / Grass Valley #2, CA
Grass Valley #2, CA: frost dates by year
Last spring and first fall frost at NOAA station USC00043573, 1967 to 2025, measured from daily minimum temperatures.
Elevation 2,400 ft, 39.204, -121.068. Download the data (JSON), NOAA daily records
Summary at 32°F
| Last spring frost | First fall frost | |
|---|---|---|
| Median | Apr 18 | Nov 6 |
| Earliest | Mar 4 (2004) | Oct 7 (1967) |
| Latest | May 23 (2010) | Dec 25 (2014) |
| Trend | 2.7 days earlier per decade | 3.5 days later per decade |
| Years with data | 57 | 56 |
At 28°F (hard freeze) the median last spring date is Mar 17 and the median first fall date is Nov 26.
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 4 | Dec 1 | Mar 7 | Dec 1 |
| 2024 | Apr 8 | Nov 16 | Feb 11 | Nov 19 |
| 2023 | Apr 20 | Oct 30 | Apr 5 | Nov 26 |
| 2022 | May 12 | Nov 3 | Apr 13 | Nov 29 |
| 2021 | Mar 25 | Nov 24 | Mar 17 | Dec 10 |
| 2020 | Apr 3 | Nov 9 | Mar 28 | Nov 9 |
| 2019 | Apr 11 | Nov 25 | Mar 15 | Nov 26 |
| 2018 | Apr 19 | Nov 9 | Mar 26 | Dec 3 |
| 2017 | Apr 15 | Nov 18 | Mar 1 | Dec 4 |
| 2016 | Mar 29 | Nov 17 | Feb 3 | Dec 2 |
| 2015 | Apr 8 | Nov 4 | Jan 4 | Nov 26 |
| 2014 | Apr 3 | Dec 25 | Feb 6 | Dec 25 |
| 2013 | Apr 17 | Nov 24 | Feb 24 | Dec 4 |
| 2012 | Apr 7 | Nov 11 | Apr 5 | Nov 11 |
| 2011 | May 15 | Nov 5 | Apr 9 | Nov 5 |
| 2010 | May 23 | Oct 27 | Mar 14 | Nov 24 |
| 2009 | Apr 29 | Oct 28 | Apr 15 | Dec 3 |
| 2008 | Apr 30 | Oct 11 | Apr 20 | Dec 9 |
| 2007 | no data | Nov 21 | no data | Nov 24 |
| 2005 | Apr 15 | no data | Jan 15 | no data |
| 2004 | Mar 4 | Oct 27 | Feb 12 | Nov 21 |
| 2003 | Apr 15 | Nov 1 | Feb 28 | Nov 22 |
| 2002 | Apr 19 | Nov 1 | Mar 19 | Dec 22 |
| 2001 | Apr 12 | Nov 26 | Mar 1 | Nov 27 |
| 2000 | May 11 | no data | Feb 24 | no data |
| 1999 | Apr 10 | Nov 22 | Apr 9 | Nov 22 |
| 1998 | Apr 16 | Nov 9 | Mar 7 | Dec 5 |
| 1997 | Apr 5 | Dec 2 | Mar 4 | Dec 10 |
| 1996 | Mar 29 | Oct 20 | Mar 6 | Nov 29 |
| 1995 | Apr 21 | Dec 16 | Mar 26 | Dec 17 |
| 1994 | Apr 26 | Nov 2 | Mar 23 | Nov 3 |
| 1993 | Apr 12 | Nov 13 | Mar 1 | Nov 24 |
| 1992 | Mar 10 | Nov 9 | Feb 3 | Nov 9 |
| 1991 | Apr 16 | Oct 30 | Mar 6 | Nov 29 |
| 1990 | Mar 14 | Nov 2 | Mar 14 | Nov 27 |
| 1989 | Apr 27 | Nov 8 | Mar 3 | Nov 27 |
| 1988 | May 1 | Nov 17 | May 1 | Nov 18 |
| 1987 | Apr 19 | Nov 15 | Mar 22 | Nov 15 |
| 1986 | May 7 | Nov 7 | Feb 11 | Dec 1 |
| 1985 | Mar 30 | Oct 13 | Mar 29 | Nov 9 |
| 1984 | Apr 28 | Oct 18 | Apr 26 | Nov 25 |
| 1983 | May 9 | Nov 8 | Apr 3 | Nov 21 |
| 1982 | Apr 18 | Oct 27 | Apr 8 | Nov 13 |
| 1981 | Apr 12 | Oct 12 | Feb 6 | Nov 29 |
| 1980 | Apr 15 | Nov 12 | Mar 27 | Nov 14 |
| 1979 | May 9 | Oct 29 | Apr 19 | Nov 20 |
| 1978 | Apr 22 | Nov 1 | Feb 17 | Nov 12 |
| 1977 | May 17 | Nov 6 | Mar 31 | Nov 19 |
| 1976 | Apr 25 | Nov 26 | Apr 16 | Nov 27 |
| 1975 | May 5 | Oct 23 | Apr 7 | Nov 18 |
| 1974 | May 19 | Nov 23 | Mar 5 | Dec 18 |
| 1973 | Apr 18 | Nov 4 | Mar 14 | Nov 4 |
| 1972 | Apr 13 | Oct 29 | Mar 27 | Nov 23 |
| 1971 | Apr 22 | Oct 17 | Mar 31 | Oct 29 |
| 1970 | Apr 29 | Oct 27 | Apr 28 | Dec 14 |
| 1969 | Apr 25 | Oct 14 | Mar 15 | Oct 14 |
| 1968 | Apr 21 | Nov 13 | Apr 21 | Nov 28 |
| 1967 | May 1 | Oct 7 | Apr 29 | Nov 26 |
"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.