Detroit Dam, OR: frost dates by year

Last spring and first fall frost at NOAA station USC00352292, 1955 to 2025, measured from daily minimum temperatures.

Elevation 1,220 ft, 44.724, -122.255. Download the data (JSON), NOAA daily records

Summary at 32°F

	Last spring frost	First fall frost
Median	Mar 27	Nov 24
Earliest	Jan 21 (1992)	Oct 11 (2008)
Latest	May 27 (2014)	Dec 29 (2020)
Trend	0.8 days earlier per decade	little change (less than half a day per decade)
Years with data	69	68, 1 with no freeze

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

"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.