Aurora, IL: frost dates by year

Last spring and first fall frost at NOAA station USC00110338, 1951 to 2025, measured from daily minimum temperatures.

Elevation 660 ft, 41.780, -88.309. Download the data (JSON) · NOAA daily records

Summary at 32°F

	Last spring frost	First fall frost
Median	Apr 26	Oct 14
Earliest	Apr 5 (1995)	Sep 20 (1956)
Latest	Jun 7 (1996)	Nov 21 (2024)
Trend	1.5 days earlier per decade	2.7 days later per decade
Years with data	71	70

At 28°F (hard freeze) the median last spring date is Apr 10 and the median first fall date is Oct 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	Apr 9	Oct 24	Apr 9	Nov 10
2024	Apr 22	Nov 21	Mar 28	Nov 21
2023	Apr 28	Oct 30	Apr 7	Oct 31
2022	Apr 18	Oct 15	Apr 18	Oct 20
2021	Apr 22	Nov 1	Apr 3	Nov 3
2020	May 10	Oct 24	Apr 17	Oct 29
2019	Apr 29	Oct 30	Apr 16	Nov 1
2018	Apr 30	Oct 13	Apr 21	Oct 21
2017	Apr 12	Nov 6	Apr 12	Nov 8
2016	Apr 13	Nov 12	Apr 10	Nov 20
2015	Apr 25	Oct 17	Apr 4	Nov 14
2014	Apr 17	Oct 19	Apr 16	Nov 2
2013	Apr 21	Oct 22	Apr 4	Oct 22
2012	Apr 12	Oct 6	Mar 11	Nov 5
2011	Apr 21	Oct 30	Mar 31	Nov 11
2010	Apr 9	Oct 29	Mar 26	Oct 29
2009	Apr 13	Oct 10	Mar 20	Oct 11
2008	Apr 29	Oct 27	Apr 2	Oct 28
2007	Apr 15	Oct 28	Apr 7	Nov 7
2006	Apr 9	Oct 12	Mar 22	Oct 26
2005	May 3	Oct 22	Mar 24	Nov 16
2004	Apr 14	Oct 17	Mar 22	Nov 13
2003	Apr 10	Oct 1	Apr 10	Oct 2
2002	May 21	no data	Apr 5	no data
2001	Apr 18	Oct 6	Apr 18	Nov 20
2000	Apr 22	Oct 6	Apr 12	Oct 6
1999	Apr 25	Oct 14	Apr 18	Oct 18
1998	Apr 18	Oct 14	Apr 5	Oct 22
1997	May 18	Oct 15	Apr 21	Oct 17
1996	Jun 7	Oct 10	Apr 26	Oct 19
1995	Apr 5	no data	Apr 5	no data
1994	May 18	Oct 26	Apr 7	Nov 16
1992	May 28	Sep 29	Apr 17	Oct 17
1991	Apr 22	Oct 14	Apr 11	Nov 2
1990	no data	Oct 10	no data	Oct 11
1989	May 10	Sep 24	May 7	Oct 4
1988	Apr 29	Oct 6	Apr 21	Oct 12
1987	no data	Oct 3	no data	Oct 8
1986	May 3	no data	Apr 23	no data
1985	Apr 10	Oct 2	Apr 9	Nov 17
1984	Apr 7	Sep 30	Apr 7	Nov 2
1983	May 9	Oct 14	Apr 20	Nov 5
1982	Apr 27	Oct 21	Apr 11	Oct 22
1981	May 12	Oct 3	Apr 6	Oct 19
1980	May 9	no data	Apr 16	no data
1979	May 1	Oct 10	Apr 10	Oct 14
1978	May 1	Oct 8	Apr 22	Nov 16
1977	May 8	Oct 13	Apr 9	Oct 17
1976	May 7	Oct 14	Apr 27	Oct 14
1975	no data	Oct 26	no data	Nov 14
1974	Apr 24	Sep 22	Apr 9	Oct 2
1973	May 4	Oct 17	Apr 13	Nov 5
1972	Apr 26	Oct 15	Apr 9	Oct 19
1971	May 12	Oct 7	Apr 7	Nov 3
1970	Apr 10	Oct 16	Apr 4	Nov 15
1969	Apr 29	Oct 14	Apr 3	Oct 23
1968	May 6	Oct 4	Apr 8	Nov 9
1967	May 3	Oct 11	May 3	Oct 21
1966	May 11	Oct 6	May 10	Oct 20
1965	May 29	Oct 5	Mar 31	Oct 28
1964	Apr 9	Oct 6	Apr 9	Oct 6
1963	May 23	Oct 30	Apr 14	Nov 2
1962	Apr 20	Oct 24	Apr 20	Oct 24
1961	May 27	Oct 2	Apr 16	Oct 27
1960	Apr 18	Oct 20	Apr 10	Oct 20
1959	Apr 22	Oct 12	Apr 22	Oct 12
1958	Apr 30	Oct 1	Apr 29	Oct 30
1957	Apr 15	Oct 11	Apr 15	Oct 20
1956	Apr 30	Sep 20	Apr 24	Nov 8
1955	Apr 8	Oct 19	Apr 8	Oct 25
1954	May 7	Oct 17	May 6	Oct 28
1953	Apr 21	Oct 7	Apr 21	Oct 29
1952	May 11	Oct 3	Apr 11	Oct 3
1951	Apr 23	Sep 28	Apr 23	Oct 29

"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 1991–2020 frost probabilities.