Parker, CO: frost dates by year

Last spring and first fall frost at NOAA station USC00056323, 1997 to 2013, measured from daily minimum temperatures.

Elevation 5,904 ft, 39.514, -104.750. Download the data (JSON), NOAA daily records

Summary at 32°F

	Last spring frost	First fall frost
Median	May 15	Oct 5
Earliest	Apr 27 (2009)	Sep 15 (2003)
Latest	Jun 8 (2007)	Oct 14 (2004)
Trend	2.5 days earlier per decade	0.6 days earlier per decade
Years with data	13	13

At 28°F (hard freeze) the median last spring date is May 3 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
2013	May 4	no data	May 3	no data
2012	May 15	no data	Apr 7	no data
2011	no data	Oct 9	no data	Oct 9
2010	May 16	Oct 9	May 7	Oct 27
2009	Apr 27	Sep 22	Apr 21	Oct 2
2008	May 11	Oct 7	May 4	Oct 7
2007	Jun 8	Sep 27	Apr 14	Oct 8
2006	May 11	Sep 17	May 11	Sep 17
2005	May 16	Oct 5	Apr 29	Oct 7
2004	May 2	Oct 14	May 1	Oct 14
2003	May 21	Sep 15	May 11	Oct 14
2002	May 25	Oct 7	May 13	Oct 13
2001	May 22	Oct 5	May 21	Oct 6
2000	no data	Sep 23	no data	Sep 24
1998	Apr 30	no data	Apr 29	no data
1997	no data	Oct 12	no data	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.