Slinger Wwtp, WI: frost dates by year

Last spring and first fall frost at NOAA station USC00477796, 2010 to 2025, measured from daily minimum temperatures.

Elevation 1,029 ft, 43.334, -88.298. Download the data (JSON), NOAA daily records

Summary at 32°F

	Last spring frost	First fall frost
Median	May 9	Oct 8
Earliest	Apr 26 (2014)	Sep 15 (2011)
Latest	May 30 (2021)	Oct 25 (2017)
Trend	1.0 days earlier per decade	9.1 days later per decade
Years with data	15	16

At 28°F (hard freeze) the median last spring date is Apr 29 and the median first fall date is Oct 15.

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	May 9	Oct 20	Apr 17	Oct 24
2024	Apr 26	Oct 7	Apr 26	Oct 16
2023	May 3	Oct 9	Apr 24	Oct 9
2022	May 5	Sep 29	Apr 28	Oct 8
2021	May 30	Oct 17	May 12	Oct 22
2020	May 12	Oct 2	May 12	Oct 5
2019	May 15	Oct 12	Apr 29	Oct 14
2018	Apr 30	Sep 29	Apr 30	Oct 13
2017	May 9	Oct 25	May 8	Nov 1
2016	May 18	Oct 13	May 15	Oct 25
2015	May 20	Oct 14	Apr 28	Oct 17
2014	Apr 26	Oct 5	Apr 23	Oct 9
2013	May 24	Oct 14	May 13	Oct 22
2012	Apr 29	Sep 19	Apr 27	Oct 12
2011	May 4	Sep 15	May 4	Oct 18
2010	no data	Oct 3	no data	Oct 4

"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.