Last Frost Day

Frost history / Carpenter 3N, WY

Carpenter 3N, WY: frost dates by year

Last spring and first fall frost at NOAA station USC00481547, 1951 to 2005, measured from daily minimum temperatures.

Elevation 5,437 ft, 41.084, -104.379. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 18Sep 22
EarliestApr 26 (1977)Sep 3 (1974)
LatestJun 16 (1981)Oct 27 (1963)
Trend1.2 days earlier per decadelittle change (less than half a day per decade)
Years with data5151

At 28°F (hard freeze) the median last spring date is May 10 and the median first fall date is Oct 1.

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 29196019701980199020001951: Jun 41952: May 131953: May 151954: Jun 31955: May 291956: May 141957: May 231958: May 11959: May 221960: May 201961: May 141962: May 151963: May 221964: Jun 21965: May 101966: May 241967: May 151968: May 191969: Jun 21970: Jun 51971: May 201972: May 41973: May 151974: Jun 71975: May 261976: May 171977: Apr 261978: May 131979: May 121980: May 261981: Jun 161982: Jun 71983: May 181985: Jun 121988: May 91989: May 61990: May 171991: May 61992: May 271993: May 111994: May 41995: May 231996: May 101997: May 121998: May 91999: May 122000: May 182001: May 212002: May 242003: May 212004: May 14

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 11196019701980199020001951: Sep 221952: Sep 221953: Sep 211954: Sep 211955: Sep 251956: Sep 231957: Sep 221958: Sep 251959: Sep 281960: Sep 301961: Sep 151962: Sep 91963: Oct 271964: Sep 241965: Sep 161966: Oct 11967: Sep 271968: Sep 91969: Oct 31970: Sep 121971: Sep 171972: Sep 211973: Oct 41974: Sep 31975: Sep 201976: Sep 281977: Oct 21978: Sep 131979: Oct 41980: Oct 101981: Sep 171982: Oct 31985: Sep 231988: Sep 301989: Sep 121990: Oct 31991: Sep 191992: Sep 181993: Sep 131994: Sep 211995: Sep 201996: Sep 261997: Oct 91998: Oct 61999: Sep 212000: Sep 222001: Sep 92002: Sep 222003: Sep 192004: Oct 102005: Sep 29

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

"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.