Crook, CO: frost dates by year

Last spring and first fall frost at NOAA station USC00051996, 2000 to 2021, measured from daily minimum temperatures.

Elevation 3,709 ft, 40.860, -102.803. Download the data (JSON), NOAA daily records

Summary at 32°F

	Last spring frost	First fall frost
Median	May 15	Oct 6
Earliest	Apr 15 (2009)	Sep 9 (2020)
Latest	May 26 (2001)	Oct 16 (2015)
Trend	1.7 days earlier per decade	little change (less than half a day per decade)
Years with data	21	21

At 28°F (hard freeze) the median last spring date is May 2 and the median first fall date is Oct 13.

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	no data	Apr 24	no data
2020	May 11	Sep 9	Apr 22	Oct 12
2019	May 23	Oct 3	May 10	Oct 3
2018	Apr 28	Oct 5	Apr 26	Oct 11
2017	May 24	Oct 9	May 4	Oct 10
2016	May 18	Oct 7	May 2	Oct 21
2015	May 12	Oct 16	Apr 21	Oct 24
2014	May 16	Oct 4	May 3	Oct 28
2013	May 6	Oct 6	May 6	Oct 16
2012	May 13	Oct 2	Apr 9	Oct 7
2011	May 15	Oct 13	May 4	Oct 18
2010	May 13	Oct 14	May 8	Oct 28
2009	Apr 15	Oct 2	Apr 9	Oct 3
2008	May 15	Oct 7	May 14	Oct 14
2007	Apr 27	Oct 8	Apr 16	Oct 16
2006	May 16	Sep 18	Apr 27	Sep 28
2005	May 4	Sep 29	May 3	Oct 6
2004	May 15	Oct 14	May 3	Oct 26
2003	May 21	Sep 15	Apr 10	Oct 1
2002	May 25	Oct 13	May 10	Oct 13
2001	May 26	Oct 6	Apr 24	Oct 16
2000	no data	Sep 25	no data	Oct 7

"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.