Frost history / W Thompson Lake, CT
W Thompson Lake, CT: frost dates by year
Last spring and first fall frost at NOAA station USC00069388, 1966 to 2025, measured from daily minimum temperatures.
Elevation 360 ft, 41.944, -71.903. Download the data (JSON), NOAA daily records
Summary at 32°F
| Last spring frost | First fall frost | |
|---|---|---|
| Median | May 9 | Oct 7 |
| Earliest | Apr 18 (2025) | Sep 15 (1975) |
| Latest | Jun 12 (1980) | Nov 2 (2023) |
| Trend | 3.2 days earlier per decade | 3.1 days later per decade |
| Years with data | 43 | 44 |
At 28°F (hard freeze) the median last spring date is Apr 25 and the median first fall date is Oct 19.
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 18 | Oct 10 | Apr 11 | Oct 27 |
| 2024 | Apr 28 | Oct 11 | Apr 26 | Oct 17 |
| 2023 | May 19 | Nov 2 | May 18 | Nov 2 |
| 2022 | no data | Oct 19 | no data | Nov 9 |
| 2021 | Apr 27 | Oct 29 | Apr 22 | Nov 3 |
| 2020 | May 14 | Oct 18 | Apr 20 | Oct 27 |
| 2019 | Apr 30 | Oct 5 | Apr 12 | Nov 5 |
| 2018 | Apr 25 | Oct 19 | Apr 23 | Oct 19 |
| 2017 | May 4 | Oct 17 | Apr 10 | Nov 9 |
| 2016 | May 10 | Oct 11 | Apr 15 | Oct 26 |
| 2015 | Apr 25 | Oct 18 | Apr 25 | Oct 18 |
| 2014 | May 7 | Oct 6 | Apr 18 | Oct 20 |
| 2013 | May 15 | Oct 21 | Apr 15 | Oct 25 |
| 2012 | Apr 29 | Oct 13 | Apr 29 | Oct 13 |
| 2011 | Apr 22 | Sep 17 | Apr 22 | Oct 31 |
| 2008 | May 2 | Oct 7 | May 1 | Oct 21 |
| 2007 | May 7 | Oct 13 | Apr 12 | Oct 29 |
| 2006 | no data | Oct 14 | no data | Oct 16 |
| 2005 | May 13 | Oct 22 | Apr 22 | Nov 12 |
| 2004 | May 5 | no data | Apr 12 | no data |
| 2003 | no data | Oct 3 | no data | Oct 20 |
| 1990 | May 12 | no data | Apr 14 | no data |
| 1989 | Apr 28 | Sep 28 | Apr 26 | Oct 10 |
| 1988 | May 9 | Oct 7 | Apr 26 | Oct 9 |
| 1987 | May 14 | Oct 5 | Apr 26 | Oct 14 |
| 1986 | May 10 | Oct 7 | May 4 | Oct 7 |
| 1985 | May 9 | Oct 12 | May 9 | Oct 21 |
| 1984 | May 19 | Oct 6 | Apr 22 | Oct 6 |
| 1983 | May 18 | Oct 21 | Apr 18 | Oct 21 |
| 1982 | Jun 9 | Oct 11 | May 1 | Oct 11 |
| 1981 | May 19 | Sep 30 | May 9 | Oct 11 |
| 1980 | Jun 12 | Sep 28 | Apr 22 | Oct 10 |
| 1979 | Apr 22 | Sep 20 | Apr 21 | Oct 27 |
| 1978 | May 4 | Sep 27 | May 2 | Oct 9 |
| 1977 | May 15 | Oct 8 | Apr 16 | Oct 24 |
| 1976 | May 13 | Oct 11 | May 5 | Oct 11 |
| 1975 | Apr 30 | Sep 15 | Apr 30 | Oct 8 |
| 1974 | May 8 | Sep 24 | May 8 | Oct 4 |
| 1973 | Apr 30 | Sep 22 | Apr 15 | Oct 22 |
| 1972 | May 27 | Oct 2 | Apr 28 | Oct 10 |
| 1971 | May 24 | Oct 8 | Apr 28 | Nov 6 |
| 1970 | May 7 | Oct 5 | Apr 20 | Oct 18 |
| 1969 | May 27 | Oct 16 | May 7 | Oct 16 |
| 1968 | May 27 | Sep 30 | May 8 | Oct 6 |
| 1967 | May 29 | Sep 26 | May 13 | Oct 21 |
| 1966 | May 14 | Sep 26 | May 3 | Oct 13 |
"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.