Chelan, WA: frost dates by year

Last spring and first fall frost at NOAA station USC00451350, 1958 to 2025, measured from daily minimum temperatures.

Elevation 1,194 ft, 47.834, -120.001. Download the data (JSON), NOAA daily records

Summary at 32°F

	Last spring frost	First fall frost
Median	Apr 12	Oct 26
Earliest	Mar 6 (2004)	Sep 20 (1983)
Latest	May 15 (2017)	Nov 19 (2010)
Trend	little change (less than half a day per decade)	0.7 days later per decade
Years with data	62	63

At 28°F (hard freeze) the median last spring date is Mar 19 and the median first fall date is Nov 9.

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 13	Oct 15	Mar 19	Nov 30
2024	May 2	Oct 23	Apr 19	Nov 18
2023	Apr 20	Oct 23	Apr 20	Oct 28
2022	Apr 28	Oct 23	Apr 6	Nov 3
2021	Apr 14	Oct 8	Apr 12	Oct 12
2020	May 4	Oct 22	Apr 13	Oct 22
2019	Apr 30	Oct 9	Mar 27	Oct 10
2018	Apr 23	Oct 30	Mar 25	Nov 9
2017	May 15	Oct 11	Mar 21	Oct 14
2016	Mar 19	Oct 12	Mar 18	Nov 29
2015	Apr 26	Nov 4	Apr 5	Nov 4
2014	Mar 21	Nov 11	Mar 4	Nov 12
2013	Mar 28	no data	Mar 26	no data
2012	no data	Nov 11	no data	Nov 11
2011	Apr 13	Oct 27	Mar 9	Nov 6
2010	no data	Nov 19	no data	Nov 20
2007	Apr 11	Oct 26	Mar 3	Nov 21
2006	Mar 19	Oct 30	Mar 13	Oct 31
2005	Apr 13	Nov 8	Feb 25	Nov 27
2004	Mar 6	Nov 4	Mar 4	Nov 23
2003	Apr 4	Oct 31	Mar 10	Nov 3
2002	Apr 24	Oct 25	Mar 22	Oct 30
2001	Apr 12	Nov 8	Mar 3	Nov 30
2000	Mar 24	Nov 11	Feb 26	Nov 11
1999	Apr 11	Nov 1	Mar 11	Dec 29
1998	Mar 29	Oct 30	Mar 7	Dec 4
1997	Apr 12	Nov 12	Mar 17	Nov 13
1996	Apr 3	no data	Mar 28	no data
1995	Mar 26	Oct 28	Mar 7	Oct 30
1994	Mar 25	Nov 3	Mar 22	Nov 3
1993	Mar 30	Nov 5	Mar 20	Nov 8
1992	Apr 8	Oct 15	Mar 29	Nov 11
1991	Mar 27	Oct 28	Mar 15	Oct 28
1990	Mar 26	Oct 20	Mar 25	Nov 6
1989	Apr 10	Oct 16	Mar 8	Dec 10
1988	Apr 9	Oct 29	Mar 28	Nov 27
1987	Mar 30	Nov 17	Mar 1	Nov 17
1986	Apr 13	Nov 8	Feb 24	Nov 9
1984	Apr 7	Oct 14	Mar 8	Oct 14
1983	Apr 14	Sep 20	Feb 21	Sep 20
1982	May 4	Oct 19	Apr 20	Oct 19
1981	May 5	Oct 13	Apr 14	Oct 21
1980	Apr 11	Oct 22	Mar 27	Oct 23
1979	Apr 20	Oct 22	Mar 13	Nov 1
1978	Apr 13	Oct 22	Mar 15	Oct 31
1977	Apr 20	Oct 10	Mar 14	Nov 8
1976	Apr 2	Oct 15	Mar 12	Nov 13
1975	Apr 21	Oct 22	Apr 3	Nov 9
1974	Apr 14	Oct 5	Mar 23	Nov 28
1973	Apr 8	Nov 3	Mar 14	Nov 3
1972	Apr 29	Oct 27	Apr 3	Oct 30
1971	Apr 16	Oct 17	Mar 20	Oct 28
1970	Apr 17	Oct 15	Mar 19	Oct 30
1969	Mar 26	Oct 13	Mar 15	Nov 17
1968	Apr 22	Oct 27	Apr 17	Nov 15
1967	Apr 25	Nov 3	Mar 14	Nov 5
1966	Apr 19	Oct 13	Mar 17	Dec 8
1965	Apr 7	Oct 16	Mar 30	Nov 26
1964	Apr 18	Oct 26	Mar 25	Nov 14
1963	Apr 2	Oct 31	Mar 13	Nov 20
1962	May 4	Nov 7	Mar 29	Nov 29
1961	Apr 20	Oct 20	Mar 7	Nov 2
1960	Apr 12	Oct 29	Mar 12	Nov 9
1959	Apr 9	Oct 30	Mar 20	Nov 5
1958	no data	Oct 24	no data	Nov 15

"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.