Last Frost Day

Frost history / Brighton 3 Se, CO

Brighton 3 Se, CO: frost dates by year

Last spring and first fall frost at NOAA station USC00050950, 1974 to 2025, measured from daily minimum temperatures.

Elevation 5,016 ft, 39.944, -104.836. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 4Oct 7
EarliestApr 9 (1985)Sep 9 (2020)
LatestMay 29 (1975)Oct 28 (2015)
Trendlittle change (less than half a day per decade)3.6 days later per decade
Years with data4548

At 28°F (hard freeze) the median last spring date is Apr 27 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)

Mar 31Apr 15Apr 30May 15May 30Jun 14198019902000201020201974: Apr 301975: May 291976: May 131977: Apr 211978: May 91981: May 101982: May 61983: May 181984: May 81985: Apr 91986: Apr 191987: Apr 211988: May 41989: May 11990: May 101992: Apr 261993: May 21994: Apr 301995: May 41996: Apr 301997: May 31998: Apr 292000: May 132001: May 212002: May 242003: May 102004: May 12007: Apr 202008: May 112010: May 132011: May 52012: Apr 162013: May 52014: May 142015: May 112016: May 82017: May 42018: Apr 252019: May 222020: Apr 292021: May 122022: May 212023: Apr 242024: Apr 212025: Apr 30

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 11198019902000201020201974: Sep 121975: Sep 201976: Sep 281978: Sep 211979: Oct 41980: Oct 101981: Oct 171982: Oct 61983: Sep 201984: Sep 251985: Sep 231986: Sep 271987: Oct 61988: Oct 211989: Oct 61990: Oct 81991: Oct 51992: Oct 81993: Sep 141995: Sep 211996: Sep 261997: Oct 91999: Sep 282001: Oct 62002: Oct 72003: Sep 152004: Oct 162005: Oct 82006: Sep 252007: Oct 82008: Oct 132009: Oct 22010: Oct 282011: Oct 182012: Oct 52013: Oct 42014: Oct 282015: Oct 282016: Oct 72017: Oct 92018: Oct 102019: Oct 72020: Sep 92021: Oct 132022: Oct 172023: Oct 142024: Oct 252025: Oct 19

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
2025Apr 30Oct 19Apr 20Oct 19
2024Apr 21Oct 25Apr 9Oct 31
2023Apr 24Oct 14Apr 23Oct 27
2022May 21Oct 17Apr 16Oct 24
2021May 12Oct 13Apr 22Oct 15
2020Apr 29Sep 9Apr 18Oct 16
2019May 22Oct 7Apr 13Oct 10
2018Apr 25Oct 10Apr 18Oct 14
2017May 4Oct 9Apr 30Oct 10
2016May 8Oct 7May 2Oct 20
2015May 11Oct 28May 10Nov 7
2014May 14Oct 28May 13Oct 29
2013May 5Oct 4May 3Oct 16
2012Apr 16Oct 5Apr 8Oct 7
2011May 5Oct 18May 5Oct 19
2010May 13Oct 28May 7Oct 28
2009no dataOct 2no dataOct 3
2008May 11Oct 13May 3Oct 23
2007Apr 20Oct 8Apr 14Oct 22
2006no dataSep 25no dataOct 18
2005no dataOct 8no dataOct 8
2004May 1Oct 16May 1Oct 25
2003May 10Sep 15Apr 9Oct 26
2002May 24Oct 7May 10Oct 13
2001May 21Oct 6Apr 23Oct 6
2000May 13no dataMay 13no data
1999no dataSep 28no dataSep 29
1998Apr 29no dataApr 29no data
1997May 3Oct 9Apr 15Oct 13
1996Apr 30Sep 26Apr 30Sep 27
1995May 4Sep 21Apr 27Sep 22
1994Apr 30no dataApr 28no data
1993May 2Sep 14Apr 20Oct 9
1992Apr 26Oct 8Apr 1Oct 8
1991no dataOct 5no dataOct 5
1990May 10Oct 8Apr 27Oct 9
1989May 1Oct 6May 1Oct 19
1988May 4Oct 21May 3Oct 23
1987Apr 21Oct 6Apr 21Oct 10
1986Apr 19Sep 27Apr 15Oct 12
1985Apr 9Sep 23Apr 9Sep 28
1984May 8Sep 25Apr 28Oct 15
1983May 18Sep 20May 12Sep 20
1982May 6Oct 6May 6Oct 7
1981May 10Oct 17Apr 5Oct 23
1980no dataOct 10no dataOct 17
1979no dataOct 4no dataOct 10
1978May 9Sep 21May 7Sep 21
1977Apr 21no dataApr 5no data
1976May 13Sep 28Apr 25Oct 7
1975May 29Sep 20May 1Oct 9
1974Apr 30Sep 12Apr 16Oct 31

"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.