Graton, CA: frost dates by year

Last spring and first fall frost at NOAA station USC00043578, 1951 to 2025, measured from daily minimum temperatures.

Elevation 200 ft, 38.431, -122.865. Download the data (JSON), NOAA daily records

Summary at 32°F

	Last spring frost	First fall frost
Median	Apr 5	Nov 8
Earliest	Feb 5 (1992)	Sep 20 (2012)
Latest	May 22 (2010)	Dec 28 (2025)
Trend	1.4 days earlier per decade	1.1 days earlier per decade
Years with data	73	74

At 28°F (hard freeze) the median last spring date is Feb 13 and the median first fall date is Nov 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	Mar 9	Dec 28	Feb 11	none
2024	no data	Nov 8	no data	Nov 30
2023	Apr 4	no data	Feb 23	no data
2022	Mar 12	Nov 3	Feb 25	Nov 20
2021	Apr 8	Dec 10	Jan 26	none
2020	Mar 27	Nov 8	none	Nov 9
2019	Mar 13	Oct 11	Feb 22	Nov 29
2018	Mar 26	Nov 9	Feb 24	Nov 9
2017	Apr 9	Nov 5	Feb 26	Nov 5
2016	Mar 29	Nov 17	Jan 2	Dec 6
2015	Apr 6	Nov 10	Feb 24	Nov 25
2014	Feb 17	Nov 17	Feb 5	Dec 27
2013	Apr 16	Oct 31	Feb 26	Nov 4
2012	Apr 8	Sep 20	Mar 7	Sep 20
2011	Apr 12	Nov 3	Mar 2	Dec 6
2010	May 22	Oct 27	none	Nov 24
2009	Apr 29	Oct 5	Mar 14	Nov 13
2008	Apr 24	Oct 11	Mar 31	Dec 6
2007	Apr 24	Oct 6	Feb 3	Nov 21
2006	Mar 19	Oct 27	Mar 13	Nov 24
2005	Apr 14	Nov 22	Jan 12	Nov 27
2004	Feb 28	Nov 20	Jan 5	Nov 22
2003	Apr 3	Nov 1	Feb 9	Nov 22
2002	Apr 28	Oct 31	Mar 8	none
2001	Apr 16	Nov 27	Apr 3	none
2000	Feb 24	Nov 10	Jan 6	Nov 10
1999	Apr 9	Nov 22	Feb 11	Dec 8
1998	Apr 15	Oct 30	none	Dec 5
1997	Apr 5	Dec 9	Jan 15	Dec 23
1996	Mar 29	Oct 20	Feb 26	Dec 2
1995	Mar 7	Oct 24	Feb 15	none
1994	Mar 23	Oct 30	Feb 13	Nov 3
1993	Feb 28	Nov 7	Jan 11	Nov 16
1992	Feb 5	Nov 10	Jan 13	Nov 11
1991	Apr 16	Oct 24	Jan 30	Dec 5
1990	Mar 13	Nov 1	Feb 20	Nov 15
1989	Mar 3	Oct 30	Feb 15	Nov 28
1988	Mar 15	Nov 18	Feb 7	Dec 26
1987	Mar 20	Nov 15	Feb 26	Nov 27
1986	Mar 14	Nov 6	Feb 8	Nov 25
1985	Mar 26	Oct 10	Mar 3	Nov 12
1984	Apr 9	Nov 1	Jan 15	Dec 16
1983	Apr 13	Nov 8	Jan 21	none
1982	Apr 9	Nov 11	Feb 12	Dec 25
1981	Apr 12	Nov 29	none	none
1980	Mar 16	Nov 12	Jan 31	Nov 13
1979	Apr 19	Nov 14	Feb 4	Nov 21
1978	Feb 11	Oct 30	none	Nov 10
1977	May 7	Nov 18	Mar 14	Nov 19
1976	Apr 2	Oct 28	Apr 2	Nov 28
1975	Apr 26	Oct 23	Feb 22	Nov 29
1974	May 18	Nov 23	Jan 11	Dec 23
1973	Apr 2	Nov 3	Jan 28	Nov 4
1972	Apr 19	Oct 31	Mar 26	Dec 5
1971	Apr 21	Oct 17	Mar 6	Oct 29
1970	Apr 29	Oct 27	Jan 7	Dec 24
1969	Apr 4	Oct 5	Feb 1	Nov 18
1968	no data	Nov 14	no data	Dec 3
1967	Apr 29	Nov 27	Jan 6	Dec 1
1966	Mar 21	Nov 23	Mar 3	Dec 27
1965	Apr 11	Nov 26	Jan 8	Dec 15
1964	Apr 24	Nov 14	Mar 7	Nov 17
1963	Apr 21	Dec 7	Jan 22	Dec 11
1962	Mar 13	Nov 29	Feb 27	Dec 25
1961	Apr 20	Nov 14	Jan 21	Nov 17
1960	Apr 24	Nov 23	Jan 13	Dec 7
1959	Feb 13	Nov 5	Feb 13	Dec 6
1958	Mar 17	Nov 16	none	Nov 16
1957	Mar 23	Nov 4	Feb 5	none
1956	Mar 13	Oct 24	Feb 18	Nov 28
1955	Apr 27	Nov 15	Mar 1	Dec 28
1954	Apr 1	Nov 29	Jan 25	Nov 30
1953	Apr 12	Nov 18	Mar 2	Dec 24
1952	May 5	Nov 3	Mar 13	Nov 24
1951	Apr 1	Nov 16	Mar 10	Dec 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.