Last Frost Day

Frost history / Cody 21 Sw, WY

Cody 21 Sw, WY: frost dates by year

Last spring and first fall frost at NOAA station USC00481855, 1964 to 2008, measured from daily minimum temperatures.

Elevation 5,840 ft, 44.337, -109.391. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianJun 9Sep 10
EarliestMay 12 (1964)Aug 15 (1974)
LatestJul 16 (1983)Oct 4 (1998)
Trendlittle change (less than half a day per decade)2.8 days later per decade
Years with data4040

At 28°F (hard freeze) the median last spring date is May 17 and the median first fall date is Sep 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 30May 15May 30Jun 14Jun 29Jul 14Jul 2919701980199020001964: May 121965: May 271971: May 221972: Jul 41973: May 301974: Jun 81975: Jun 111976: Jun 271977: May 301978: Jun 201979: Jun 91980: May 281981: Jun 181982: Jun 91983: Jul 161984: Jun 231985: Jun 121986: Jul 61987: Jun 21988: May 221989: Jun 221990: Jun 31991: Jun 151992: May 131993: Jun 41994: Jun 171995: Jun 91996: May 241997: May 191998: Jun 61999: Jun 102000: Jun 172001: Jun 132002: May 242003: May 212004: Jun 172005: Jun 92006: May 312007: Jun 82008: Jun 11

First fall frost (32°F)

Jul 29Aug 13Aug 28Sep 12Sep 27Oct 1219701980199020001964: Sep 41970: Sep 101971: Sep 141972: Sep 211973: Sep 141974: Aug 151975: Sep 11976: Aug 271977: Aug 281978: Aug 181979: Sep 111980: Sep 41981: Sep 221982: Sep 121983: Sep 61984: Sep 111985: Sep 81986: Aug 251987: Aug 181988: Sep 111989: Aug 261990: Sep 291991: Sep 181992: Aug 261993: Aug 271994: Sep 221995: Sep 191996: Sep 61997: Sep 201998: Oct 41999: Sep 82000: Sep 202001: Sep 82002: Sep 212003: Sep 132004: Sep 212005: Sep 132006: Sep 12007: Sep 102008: Sep 8

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
2008Jun 11Sep 8May 10Oct 9
2007Jun 8Sep 10May 24Oct 20
2006May 31Sep 1May 9Sep 24
2005Jun 9Sep 13May 13Oct 4
2004Jun 17Sep 21May 14Sep 21
2003May 21Sep 13May 20Sep 17
2002May 24Sep 21May 24Sep 22
2001Jun 13Sep 8May 21Sep 22
2000Jun 17Sep 20Jun 1Sep 20
1999Jun 10Sep 8May 17Sep 13
1998Jun 6Oct 4May 9Oct 5
1997May 19Sep 20May 19Oct 6
1996May 24Sep 6May 11Sep 23
1995Jun 9Sep 19May 14Sep 20
1994Jun 17Sep 22Apr 30Sep 22
1993Jun 4Aug 27May 9Sep 14
1992May 13Aug 26May 13Aug 26
1991Jun 15Sep 18May 5Sep 18
1990Jun 3Sep 29May 17Oct 3
1989Jun 22Aug 26May 26Oct 2
1988May 22Sep 11May 20Oct 18
1987Jun 2Aug 18Jun 2Sep 17
1986Jul 6Aug 25May 24Sep 21
1985Jun 12Sep 8May 14Sep 13
1984Jun 23Sep 11May 22Sep 13
1983Jul 16Sep 6May 31Sep 10
1982Jun 9Sep 12Jun 7Sep 14
1981Jun 18Sep 22May 12Sep 23
1980May 28Sep 4May 14Sep 22
1979Jun 9Sep 11Jun 8Sep 14
1978Jun 20Aug 18Apr 24Sep 19
1977May 30Aug 28May 29Sep 9
1976Jun 27Aug 27May 16Sep 8
1975Jun 11Sep 1May 25Sep 19
1974Jun 8Aug 15May 18Sep 3
1973May 30Sep 14May 30Sep 15
1972Jul 4Sep 21May 9Sep 24
1971May 22Sep 14Apr 27Sep 18
1970no dataSep 10no dataSep 12
1965May 27no dataMay 18no data
1964May 12Sep 4May 12Sep 27

"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.