Frost history / Monument 3S, CO
Monument 3S, CO: frost dates by year
Last spring and first fall frost at NOAA station USC00055733, 2009 to 2021, measured from daily minimum temperatures.
Elevation 6,821 ft, 39.056, -104.868. Download the data (JSON), NOAA daily records
Summary at 32°F
| Last spring frost | First fall frost | |
|---|---|---|
| Median | May 19 | Oct 3 |
| Earliest | May 4 (2018) | Sep 8 (2020) |
| Latest | May 25 (2020) | Oct 24 (2015) |
| Trend | 1.3 days earlier per decade | 6.1 days earlier per decade |
| Years with data | 10 | 12 |
At 28°F (hard freeze) the median last spring date is May 11 and the median first fall date is Oct 8.
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 |
|---|---|---|---|---|
| 2021 | May 12 | Sep 22 | Apr 23 | Oct 14 |
| 2020 | May 25 | Sep 8 | May 10 | Sep 9 |
| 2019 | May 24 | Oct 4 | May 22 | Oct 7 |
| 2018 | May 4 | Oct 10 | Apr 27 | Oct 10 |
| 2017 | May 24 | Oct 9 | May 20 | Oct 9 |
| 2016 | May 12 | Sep 26 | May 12 | Oct 5 |
| 2015 | no data | Oct 24 | no data | Oct 28 |
| 2014 | May 14 | no data | May 13 | no data |
| 2013 | no data | Sep 28 | no data | Sep 28 |
| 2012 | May 20 | Oct 4 | Apr 30 | Oct 4 |
| 2011 | May 20 | Oct 9 | May 6 | Oct 11 |
| 2010 | May 18 | Oct 3 | May 13 | Oct 20 |
| 2009 | no data | Sep 22 | no data | Oct 2 |
"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.