Chelsea, MI: frost dates by year

Last spring and first fall frost at NOAA station USC00201502, 2002 to 2025, measured from daily minimum temperatures.

Elevation 900 ft, 42.326, -84.013. Download the data (JSON), NOAA daily records

Summary at 32°F

	Last spring frost	First fall frost
Median	May 3	Oct 14
Earliest	Apr 16 (2019)	Sep 19 (2020)
Latest	May 28 (2008)	Oct 28 (2007)
Trend	3.7 days earlier per decade	2.1 days later per decade
Years with data	22	24

At 28°F (hard freeze) the median last spring date is Apr 24 and the median first fall date is Oct 21.

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 17	Oct 10	Apr 17	Nov 2
2024	Apr 26	Oct 17	Apr 25	Oct 27
2023	May 18	Oct 23	Apr 26	Oct 31
2022	Apr 28	Oct 8	Apr 28	Oct 21
2021	May 10	Oct 24	May 1	Nov 3
2020	May 13	Sep 19	May 13	Oct 16
2019	Apr 16	Oct 15	Apr 1	Nov 6
2018	Apr 30	Oct 14	Apr 21	Oct 16
2017	May 9	Oct 26	Apr 8	Oct 26
2016	Apr 25	Oct 14	Apr 14	Nov 12
2015	Apr 28	Oct 17	Apr 28	Oct 17
2014	May 6	Oct 11	Apr 16	Oct 12
2013	May 13	Oct 22	May 13	Oct 27
2012	Apr 29	Oct 8	Apr 29	Oct 8
2011	Apr 19	Oct 22	Apr 6	Oct 22
2010	May 10	Oct 19	Apr 10	Oct 22
2009	May 18	Oct 1	Apr 12	Oct 18
2008	May 28	Oct 4	Apr 30	Oct 19
2007	May 12	Oct 28	Apr 13	Oct 29
2006	Apr 27	Oct 6	Apr 25	Oct 14
2005	May 6	Oct 16	May 4	Oct 26
2004	no data	Oct 3	no data	Oct 5
2003	Apr 27	Oct 2	Apr 24	Oct 2
2002	no data	Oct 14	no data	Oct 14

"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.