Last Frost Day

Frost history / Denver Centennial Ap, CO

Denver Centennial Ap, CO: frost dates by year

Last spring and first fall frost at NOAA station USW00093067, 1998 to 2024, measured from daily minimum temperatures.

Elevation 5,883 ft, 39.570, -104.849. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 11Oct 7
EarliestApr 20 (2020)Sep 8 (2020)
LatestMay 24 (2002)Oct 31 (2024)
Trend2.2 days earlier per decade5.6 days later per decade
Years with data2627

At 28°F (hard freeze) the median last spring date is Apr 27 and the median first fall date is Oct 20.

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)

Apr 15Apr 30May 15May 302000201020201999: May 172000: May 142001: May 212002: May 242003: May 112004: May 142005: May 122006: May 112007: Apr 262008: May 32009: Apr 272010: May 132011: May 52012: Apr 282013: May 42014: May 142015: May 112016: May 22017: May 202018: May 22019: May 212020: Apr 202021: May 122022: May 212023: May 112024: May 8

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 112000201020201998: Oct 41999: Sep 282000: Sep 222001: Oct 42002: Oct 42003: Sep 142004: Oct 132005: Oct 62006: Sep 172007: Oct 82008: Oct 132009: Oct 22010: Oct 262011: Oct 92012: Oct 52013: Sep 282014: Sep 122015: Oct 282016: Oct 72017: Oct 82018: Oct 92019: Oct 92020: Sep 82021: Oct 132022: Oct 172023: Oct 142024: Oct 31

Dots are single years. The gray line is the median, the green line the fitted trend.

Year by year

YearLast spring 32°FFirst fall 32°FLast spring 28°FFirst fall 28°F
2024May 8Oct 31Apr 9Oct 31
2023May 11Oct 14Apr 23Oct 28
2022May 21Oct 17Apr 18Oct 24
2021May 12Oct 13Apr 22Oct 20
2020Apr 20Sep 8Apr 17Oct 22
2019May 21Oct 9Apr 13Oct 10
2018May 2Oct 9Apr 25Oct 13
2017May 20Oct 8Apr 30Oct 9
2016May 2Oct 7May 2Oct 20
2015May 11Oct 28May 10Nov 6
2014May 14Sep 12Apr 14Nov 4
2013May 4Sep 28May 3Oct 4
2012Apr 28Oct 5Mar 21Oct 7
2011May 5Oct 9Apr 28Oct 19
2010May 13Oct 26Apr 30Oct 27
2009Apr 27Oct 2Apr 10Oct 9
2008May 3Oct 13May 3Oct 23
2007Apr 26Oct 8Apr 14Oct 21
2006May 11Sep 17Apr 26Oct 17
2005May 12Oct 6Apr 29Oct 7
2004May 14Oct 13May 1Oct 30
2003May 11Sep 14Apr 8Oct 25
2002May 24Oct 4May 9Oct 22
2001May 21Oct 4May 21Oct 6
2000May 14Sep 22May 13Sep 25
1999May 17Sep 28May 12Sep 28
1998no dataOct 4no dataOct 6

"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.