Last Frost Day

Frost history / Tensleep 16SSE, WY

Tensleep 16SSE, WY: frost dates by year

Last spring and first fall frost at NOAA station USC00488858, 1959 to 2025, measured from daily minimum temperatures.

Elevation 4,680 ft, 43.811, -107.365. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 26Sep 14
EarliestMay 4 (1992)Aug 5 (1980)
LatestJul 4 (1972)Oct 8 (1963)
Trendlittle change (less than half a day per decade)little change (less than half a day per decade)
Years with data6364

At 28°F (hard freeze) the median last spring date is May 8 and the median first fall date is Sep 22.

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 1419601970198019902000201020201960: Jun 211961: May 71962: May 151963: May 201966: Jun 131967: May 131968: May 201969: Jun 141970: May 151971: May 191972: Jul 41973: Jun 181974: Jun 11975: May 261976: May 171977: May 291978: May 201979: Jun 91980: May 141981: Jun 181982: Jun 91983: Jun 11984: Jun 31985: May 311986: May 251987: Jun 31988: May 221989: May 281990: Jun 21991: May 61992: May 41993: May 101994: May 221995: May 251996: May 211997: May 201998: Jun 41999: May 182000: Jun 12001: May 212002: Jun 112003: Jun 82004: May 272005: Jun 102006: May 302007: May 272008: Jun 132009: May 162010: May 232011: May 302012: May 282013: May 62014: Jun 192015: May 212016: May 242017: May 202018: May 52019: Jun 222020: May 222021: May 242022: Jun 152023: May 102025: Jun 18

First fall frost (32°F)

Jul 29Aug 13Aug 28Sep 12Sep 27Oct 12Oct 2719601970198019902000201020201959: Sep 221960: Sep 91961: Sep 41962: Sep 41963: Oct 81966: Aug 221967: Oct 71968: Sep 171969: Sep 231970: Sep 101971: Sep 151972: Sep 141973: Sep 151974: Sep 21975: Sep 121976: Sep 91977: Sep 91978: Sep 191979: Sep 141980: Aug 51981: Sep 171982: Sep 141983: Sep 61984: Sep 71985: Sep 131986: Sep 221987: Sep 121988: Sep 291989: Sep 111990: Sep 231991: Sep 171992: Aug 271993: Aug 311994: Sep 221995: Sep 201996: Sep 231997: Sep 281998: Oct 51999: Sep 132000: Sep 72001: Sep 92002: Sep 222003: Sep 182004: Sep 152005: Aug 312006: Sep 242007: Sep 102008: Sep 142009: Sep 222010: Sep 32011: Sep 182012: Sep 132013: Sep 272014: Sep 122015: Aug 232016: Sep 102017: Sep 172018: Sep 212019: Sep 182020: Sep 12021: Sep 172022: Sep 112023: Sep 242024: Sep 13

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

"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.