Frost history / Highmore 23 N, SD
Highmore 23 N, SD: frost dates by year
Last spring and first fall frost at NOAA station USC00393838, 1963 to 2009, measured from daily minimum temperatures.
Elevation 1,870 ft, 44.844, -99.489. Download the data (JSON), NOAA daily records
Summary at 32°F
| Last spring frost | First fall frost | |
|---|---|---|
| Median | May 17 | Sep 20 |
| Earliest | Apr 17 (2007) | Aug 12 (1964) |
| Latest | Jul 30 (1971) | Oct 23 (1994) |
| Trend | 6.5 days earlier per decade | 3.5 days later per decade |
| Years with data | 35 | 41 |
At 28°F (hard freeze) the median last spring date is May 10 and the median first fall date is Sep 27.
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 |
|---|---|---|---|---|
| 2009 | no data | Sep 28 | no data | Oct 8 |
| 2008 | May 11 | Oct 13 | May 10 | Oct 15 |
| 2007 | Apr 17 | no data | Apr 16 | no data |
| 2006 | May 12 | Sep 17 | May 11 | Oct 8 |
| 2005 | May 14 | Oct 5 | May 14 | Oct 6 |
| 2004 | no data | Oct 2 | no data | Oct 2 |
| 2003 | May 21 | Sep 25 | Apr 10 | Sep 30 |
| 2000 | Apr 21 | no data | Apr 17 | no data |
| 1998 | no data | Oct 1 | no data | Oct 1 |
| 1997 | May 20 | no data | Apr 16 | no data |
| 1996 | no data | Oct 3 | no data | Oct 21 |
| 1995 | no data | Sep 21 | no data | Sep 22 |
| 1994 | no data | Oct 23 | no data | Oct 24 |
| 1993 | May 20 | Sep 14 | Apr 21 | Oct 9 |
| 1992 | May 27 | Sep 8 | May 27 | Sep 28 |
| 1991 | May 7 | Sep 19 | May 7 | Sep 19 |
| 1990 | May 11 | Sep 16 | May 10 | Sep 23 |
| 1989 | May 6 | Sep 11 | May 6 | Sep 22 |
| 1988 | May 16 | Sep 23 | May 13 | Oct 4 |
| 1987 | Apr 22 | Oct 2 | Apr 22 | Oct 2 |
| 1986 | May 18 | Sep 7 | Apr 21 | Oct 12 |
| 1985 | Jun 3 | Sep 19 | May 7 | Sep 23 |
| 1984 | May 26 | Sep 15 | May 26 | Sep 26 |
| 1983 | Jun 1 | Sep 20 | May 14 | Sep 21 |
| 1982 | May 8 | Sep 20 | Apr 22 | Sep 21 |
| 1981 | May 19 | Sep 16 | May 13 | Sep 17 |
| 1980 | May 14 | Sep 26 | May 8 | Oct 3 |
| 1979 | May 24 | Sep 14 | May 11 | Sep 21 |
| 1978 | Apr 25 | Sep 21 | Apr 25 | Sep 21 |
| 1977 | Apr 25 | Oct 2 | Apr 24 | Oct 2 |
| 1976 | May 17 | Sep 23 | May 17 | Sep 23 |
| 1975 | May 12 | Sep 12 | May 3 | Sep 24 |
| 1974 | Jun 16 | Sep 3 | May 24 | Sep 3 |
| 1973 | May 17 | Sep 16 | May 17 | Sep 16 |
| 1972 | May 7 | Sep 26 | May 7 | Sep 26 |
| 1971 | Jul 30 | Sep 16 | May 20 | Sep 18 |
| 1970 | May 26 | Sep 13 | May 4 | Sep 26 |
| 1969 | Jun 20 | Oct 8 | May 17 | Oct 8 |
| 1968 | May 25 | Oct 3 | May 24 | Oct 3 |
| 1967 | May 20 | Sep 27 | May 20 | Sep 27 |
| 1966 | no data | Sep 14 | no data | Oct 1 |
| 1965 | no data | Sep 5 | no data | Sep 24 |
| 1964 | Jun 2 | Aug 12 | Jun 2 | Sep 12 |
| 1963 | no data | Sep 29 | no data | Oct 27 |
"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.