Last Frost Day

Frost history / Ouray, CO

Ouray, CO: frost dates by year

Last spring and first fall frost at NOAA station USC00056203, 1951 to 2005, measured from daily minimum temperatures.

Elevation 7,840 ft, 38.021, -107.669. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 28Sep 25
EarliestMay 3 (1958)Sep 3 (1961)
LatestJun 27 (1985)Oct 27 (1963)
Trend0.5 days later per decade1.2 days earlier per decade
Years with data5454

At 28°F (hard freeze) the median last spring date is May 10 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)

Apr 15Apr 30May 15May 30Jun 14Jun 29Jul 14196019701980199020001951: Jun 111952: May 231953: May 301954: Jun 71955: May 291956: May 161957: Jun 171958: May 31959: May 51960: May 251961: May 141962: May 281963: May 121964: May 121965: May 281966: May 131967: May 151968: May 181969: Jun 251970: Jun 121971: May 241972: May 141973: Jun 191974: Jun 91975: Jun 111976: Jun 151978: May 191979: Jun 191980: May 271981: Jun 161982: Jun 61983: Jun 141984: Jun 91985: Jun 271986: May 181987: May 281988: Jun 11989: Jun 221990: Jun 21991: May 161992: May 101993: Jun 71994: May 101995: Jun 181996: May 271997: May 271998: May 151999: Jun 62000: May 182001: Jun 142002: May 242003: May 112004: May 302005: May 12

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 11196019701980199020001951: Sep 121952: Sep 141953: Oct 141954: Oct 111955: Sep 271956: Oct 131957: Sep 221958: Oct 211959: Sep 251960: Oct 121961: Sep 31962: Sep 91963: Oct 271964: Sep 201965: Sep 201966: Oct 31967: Oct 71968: Sep 161969: Oct 31970: Sep 251971: Sep 171972: Sep 301973: Sep 261974: Sep 281975: Sep 201977: Oct 11978: Sep 191979: Oct 211980: Oct 151981: Oct 91982: Sep 141983: Sep 201984: Sep 251985: Sep 121986: Sep 301987: Oct 161988: Sep 151989: Sep 141990: Oct 81991: Sep 161992: Sep 261993: Sep 141994: Oct 81995: Sep 221996: Sep 181997: Oct 81998: Oct 51999: Sep 282000: Sep 242001: Sep 92002: Oct 32003: Sep 142004: Sep 52005: Oct 5

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