Last Frost Day

Frost history / Montrose #2, CO

Montrose #2, CO: frost dates by year

Last spring and first fall frost at NOAA station USC00055722, 1951 to 2025, measured from daily minimum temperatures.

Elevation 5,789 ft, 38.486, -107.879. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 8Oct 9
EarliestApr 14 (2019)Sep 10 (1962)
LatestJun 2 (1990)Oct 31 (2005)
Trend2.0 days earlier per decade0.8 days later per decade
Years with data7173

At 28°F (hard freeze) the median last spring date is Apr 24 and the median first fall date is Oct 19.

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 1419601970198019902000201020201951: May 31952: Apr 161953: May 131954: May 31955: May 281956: May 151957: May 221958: Apr 261959: Apr 231960: May 201961: May 51962: May 161963: May 131964: May 91965: May 281966: Apr 291967: May 151968: May 251969: Apr 291970: May 151971: May 191972: May 121973: May 271974: May 211975: May 71976: May 11977: May 191978: May 91979: May 131980: May 131981: May 131982: May 61983: May 181984: May 71985: May 141986: May 101987: Apr 221988: May 71989: Apr 301990: Jun 21991: May 51992: Apr 211993: May 61994: Apr 281995: May 51996: Apr 301997: May 41998: May 161999: May 172000: May 132001: May 42002: May 222003: May 122004: Apr 262005: Apr 302006: May 102007: Apr 242008: May 132010: May 122011: May 112012: Apr 172013: May 32014: May 142015: Apr 192016: Apr 192018: Apr 262019: Apr 142020: Apr 172021: Apr 212023: Apr 222024: May 8

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 1119601970198019902000201020201951: Oct 71952: Oct 71953: Oct 221954: Oct 141955: Oct 61956: Oct 131957: Oct 231958: Oct 211959: Sep 251960: Oct 131961: Sep 251962: Sep 101963: Oct 281964: Oct 121965: Sep 211966: Oct 141967: Oct 71968: Sep 161969: Oct 41970: Sep 251971: Sep 181972: Oct 241973: Oct 101974: Oct 301975: Oct 91976: Oct 71977: Oct 11978: Sep 201979: Oct 221980: Oct 181981: Oct 171982: Oct 61983: Sep 211984: Sep 291985: Sep 291986: Sep 301987: Oct 171988: Sep 191989: Oct 171990: Oct 91991: Oct 51992: Sep 261993: Oct 191994: Oct 31995: Sep 221996: Sep 191997: Oct 91998: Oct 62001: Oct 102002: Oct 132003: Oct 142004: Oct 142005: Oct 312006: Sep 172007: Sep 302008: Oct 122009: Sep 222010: Oct 262011: Oct 72012: Oct 72013: Sep 282014: Oct 132015: Oct 282016: Oct 42017: Oct 32018: Oct 152019: Oct 62020: Oct 152021: Oct 132022: Oct 232023: Oct 282024: Oct 182025: Oct 17

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
2025no dataOct 17no dataOct 28
2024May 8Oct 18Apr 9Oct 30
2023Apr 22Oct 28Apr 21Oct 29
2022no dataOct 23no dataOct 24
2021Apr 21Oct 13Apr 20Oct 15
2020Apr 17Oct 15Apr 16Oct 25
2019Apr 14Oct 6Apr 14Oct 10
2018Apr 26Oct 15Apr 19Oct 15
2017no dataOct 3no dataOct 10
2016Apr 19Oct 4Apr 6Nov 18
2015Apr 19Oct 28Apr 17Nov 7
2014May 14Oct 13May 1Nov 4
2013May 3Sep 28May 2Oct 19
2012Apr 17Oct 7Apr 13Oct 26
2011May 11Oct 7May 2Oct 7
2010May 12Oct 26May 7Oct 26
2009no dataSep 22no dataOct 2
2008May 13Oct 12May 4Oct 13
2007Apr 24Sep 30Apr 12Oct 18
2006May 10Sep 17Apr 20Oct 19
2005Apr 30Oct 31Apr 21Nov 1
2004Apr 26Oct 14Mar 30Oct 23
2003May 12Oct 14May 11Oct 26
2002May 22Oct 13Apr 21Oct 30
2001May 4Oct 10Apr 14Oct 11
2000May 13no dataApr 30no data
1999May 17no dataMay 7no data
1998May 16Oct 6Apr 19Nov 4
1997May 4Oct 9May 2Oct 14
1996Apr 30Sep 19Apr 30Oct 17
1995May 5Sep 22Apr 21Oct 6
1994Apr 28Oct 3Apr 13Oct 31
1993May 6Oct 19Apr 20Oct 27
1992Apr 21Sep 26Mar 25Oct 8
1991May 5Oct 5Apr 30Oct 29
1990Jun 2Oct 9May 9Oct 9
1989Apr 30Oct 17Apr 29Oct 19
1988May 7Sep 19May 7Nov 6
1987Apr 22Oct 17Apr 22Nov 9
1986May 10Sep 30Apr 27Oct 12
1985May 14Sep 29Apr 23Oct 15
1984May 7Sep 29Apr 27Oct 16
1983May 18Sep 21Apr 17Nov 8
1982May 6Oct 6May 6Oct 10
1981May 13Oct 17Apr 6Oct 25
1980May 13Oct 18Apr 14Oct 18
1979May 13Oct 22Apr 13Oct 22
1978May 9Sep 20Apr 22Sep 20
1977May 19Oct 1Apr 5Oct 12
1976May 1Oct 7Apr 28Oct 7
1975May 7Oct 9Apr 30Oct 9
1974May 21Oct 30Apr 17Oct 30
1973May 27Oct 10Apr 20Oct 25
1972May 12Oct 24May 1Oct 30
1971May 19Sep 18Apr 28Sep 19
1970May 15Sep 25May 3Sep 26
1969Apr 29Oct 4Apr 27Oct 5
1968May 25Sep 16May 8Oct 9
1967May 15Oct 7May 3Oct 15
1966Apr 29Oct 14Apr 28Oct 14
1965May 28Sep 21Apr 15Sep 21
1964May 9Oct 12Apr 27Oct 25
1963May 13Oct 28Apr 24Nov 1
1962May 16Sep 10May 1Nov 7
1961May 5Sep 25Apr 26Sep 30
1960May 20Oct 13May 20Oct 29
1959Apr 23Sep 25Apr 22Oct 8
1958Apr 26Oct 21Apr 26Oct 21
1957May 22Oct 23Apr 26Oct 26
1956May 15Oct 13Apr 10Oct 21
1955May 28Oct 6Apr 28Oct 6
1954May 3Oct 14Apr 2Oct 14
1953May 13Oct 22May 11Oct 22
1952Apr 16Oct 7Apr 4Oct 15
1951May 3Oct 7May 2Oct 23

"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.