Frost history / San Luis 1 S, CO
San Luis 1 S, CO: frost dates by year
Last spring and first fall frost at NOAA station USC00057430, 1980 to 2005, measured from daily minimum temperatures.
Elevation 7,943 ft, 37.195, -105.424. Download the data (JSON), NOAA daily records
Summary at 32°F
| Last spring frost | First fall frost | |
|---|---|---|
| Median | Jun 11 | Sep 20 |
| Earliest | May 12 (2003) | Aug 8 (1988) |
| Latest | Jul 11 (1987) | Oct 14 (2003) |
| Trend | 10.4 days earlier per decade | 8.9 days later per decade |
| Years with data | 20 | 23 |
At 28°F (hard freeze) the median last spring date is May 16 and the median first fall date is Sep 23.
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 |
|---|---|---|---|---|
| 2005 | May 13 | Sep 14 | May 12 | Oct 24 |
| 2004 | May 31 | Sep 23 | May 31 | Sep 23 |
| 2003 | May 12 | Oct 14 | May 11 | Oct 14 |
| 2002 | May 25 | Sep 20 | Apr 22 | Sep 20 |
| 2001 | May 22 | Sep 9 | Apr 24 | Sep 9 |
| 2000 | no data | Sep 25 | no data | Sep 25 |
| 1999 | Jun 11 | Sep 20 | Jun 5 | Sep 21 |
| 1998 | Jun 18 | Sep 27 | Jun 18 | Sep 27 |
| 1997 | Jul 2 | Oct 4 | May 3 | Oct 9 |
| 1996 | no data | Sep 19 | no data | Sep 19 |
| 1995 | no data | Sep 22 | no data | Sep 23 |
| 1993 | Jun 11 | no data | Jun 11 | no data |
| 1992 | Jun 18 | Sep 22 | May 11 | Sep 25 |
| 1991 | Jun 3 | Sep 13 | May 13 | Sep 15 |
| 1990 | Jun 20 | Oct 4 | Jun 2 | Oct 9 |
| 1989 | Jun 5 | Sep 9 | May 5 | Sep 14 |
| 1988 | no data | Aug 8 | no data | Sep 19 |
| 1987 | Jul 11 | Sep 9 | Jun 1 | Sep 11 |
| 1986 | May 30 | no data | May 27 | no data |
| 1985 | Jun 27 | Aug 13 | May 15 | Sep 13 |
| 1984 | Jun 10 | Sep 9 | May 9 | Sep 30 |
| 1983 | Jun 14 | Sep 21 | Jun 14 | Sep 21 |
| 1982 | Jun 9 | Sep 29 | May 18 | Sep 29 |
| 1981 | Jun 16 | Sep 14 | May 27 | Oct 6 |
| 1980 | no data | Aug 21 | no data | Sep 22 |
"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.