Beloit, WI: frost dates by year

Last spring and first fall frost at NOAA station USC00470696, 1951 to 2025, measured from daily minimum temperatures.

Elevation 788 ft, 42.504, -89.031. Download the data (JSON), NOAA daily records

Summary at 32°F

	Last spring frost	First fall frost
Median	Apr 23	Oct 12
Earliest	Mar 28 (1999)	Sep 20 (1956)
Latest	May 22 (2002)	Nov 12 (2016)
Trend	little change (less than half a day per decade)	1.5 days later per decade
Years with data	72	66

At 28°F (hard freeze) the median last spring date is Apr 10 and the median first fall date is Oct 25.

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 9	Oct 24	Apr 9	Nov 10
2024	Apr 25	Oct 16	Mar 29	Oct 16
2023	Apr 27	Oct 30	Apr 18	Oct 30
2022	Apr 28	Oct 8	Apr 17	Oct 20
2021	Apr 23	Nov 1	Apr 3	Nov 3
2020	May 11	Oct 20	Apr 17	Oct 28
2019	Apr 29	Oct 25	Apr 29	Oct 30
2018	Apr 30	Oct 13	Apr 30	Oct 13
2017	May 4	Oct 28	Apr 2	Oct 30
2016	Apr 13	Nov 12	Apr 10	Nov 12
2015	Apr 27	Oct 17	Apr 25	Oct 18
2014	Apr 24	Oct 11	Apr 17	Nov 1
2013	Apr 22	Oct 21	Apr 21	Oct 22
2012	Apr 28	Oct 7	Mar 11	Oct 28
2011	May 5	Oct 3	Apr 22	Nov 11
2010	Apr 29	Oct 22	Apr 10	Oct 29
2009	Apr 13	Oct 10	Mar 31	Oct 11
2008	Apr 15	Oct 22	Apr 3	Oct 28
2007	Apr 17	Oct 28	Apr 16	Nov 7
2006	Apr 27	Oct 12	Apr 9	Oct 12
2005	May 6	Oct 23	Mar 29	Oct 28
2004	May 4	Oct 5	Apr 14	Oct 6
2003	Apr 14	Oct 2	Apr 11	Oct 2
2002	May 22	Oct 14	Apr 7	Oct 21
2001	Apr 19	Oct 7	Apr 2	Oct 7
2000	Apr 13	Oct 7	Apr 9	Oct 9
1999	Mar 28	Oct 14	Mar 27	Oct 24
1998	Apr 18	Oct 22	Mar 25	Nov 5
1997	Apr 19	Oct 15	Apr 14	Oct 28
1996	Apr 18	Oct 11	Apr 14	Oct 11
1995	Apr 15	Sep 23	Apr 6	Nov 3
1994	Apr 8	Oct 27	Apr 8	Nov 16
1993	Apr 22	Sep 30	Apr 6	Oct 21
1992	May 5	Oct 17	Apr 13	Oct 17
1991	Apr 3	Sep 26	Apr 2	Oct 20
1990	Apr 19	Oct 10	Apr 19	Oct 19
1989	May 7	no data	Apr 14	no data
1988	Apr 22	Oct 6	Apr 22	Oct 13
1987	Apr 5	Oct 3	Apr 5	Oct 8
1986	Apr 23	no data	Apr 22	no data
1985	Apr 10	Oct 6	Apr 9	Nov 20
1984	Apr 19	Sep 29	Apr 1	Oct 23
1983	Apr 20	Oct 13	Apr 19	Nov 5
1982	Apr 22	Oct 21	Apr 11	Oct 22
1981	May 12	Oct 3	Apr 20	Oct 23
1980	May 7	Oct 4	Apr 13	Oct 5
1979	May 1	Oct 5	Apr 10	Oct 26
1978	May 2	Oct 8	May 1	Nov 7
1977	no data	Oct 13	no data	Nov 11
1975	Apr 22	no data	Apr 7	no data
1974	no data	Sep 22	no data	Oct 2
1973	Apr 13	no data	Apr 13	no data
1972	Apr 26	Oct 15	Apr 9	Oct 18
1971	May 3	Nov 1	Apr 6	Nov 4
1970	May 7	no data	Apr 4	no data
1969	Apr 29	Sep 26	Apr 3	Oct 23
1968	Apr 15	Oct 4	Apr 6	Nov 4
1967	Apr 25	Oct 12	Apr 23	Oct 28
1966	May 11	Oct 6	May 10	Oct 25
1965	Apr 27	Oct 28	Apr 3	Nov 14
1964	Apr 15	Oct 7	Apr 9	Oct 10
1963	May 1	Nov 2	Apr 10	Nov 2
1962	Apr 20	Oct 24	Apr 20	Oct 25
1961	May 1	Oct 2	Apr 16	Nov 6
1960	Apr 18	Oct 20	Apr 10	Oct 20
1959	Apr 22	no data	Apr 11	no data
1958	Apr 29	no data	Apr 29	no data
1957	Apr 15	Oct 19	Apr 15	Oct 25
1956	Apr 30	Sep 20	Apr 24	Nov 8
1955	Apr 7	Oct 22	Mar 29	Nov 3
1954	May 7	no data	Apr 4	no data
1953	Apr 21	Oct 7	Apr 20	Nov 5
1952	Apr 16	Oct 3	Apr 11	Oct 3
1951	Apr 23	Oct 8	Apr 16	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.