Last Frost Day

Frost history / Tensleep 4NE, WY

Tensleep 4NE, WY: frost dates by year

Last spring and first fall frost at NOAA station USC00488852, 1964 to 2025, measured from daily minimum temperatures.

Elevation 4,748 ft, 44.065, -107.382. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 12Oct 1
EarliestApr 13 (1987)Aug 31 (2019)
LatestJun 13 (1970)Oct 25 (2023)
Trend2.5 days earlier per decade1.6 days later per decade
Years with data5658

At 28°F (hard freeze) the median last spring date is Apr 30 and the median first fall date is Oct 9.

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 14Jun 291970198019902000201020201965: May 271966: May 231967: May 121968: May 181969: May 211970: Jun 131971: May 191972: May 21973: May 281974: May 221975: May 251976: May 21977: May 191978: May 191979: May 301980: May 131981: May 121982: May 311983: May 171984: May 171985: May 141986: May 231987: Apr 131988: May 81989: May 251990: May 161991: May 41992: Apr 251993: Apr 241994: Apr 301995: May 141996: May 111997: May 31998: Apr 261999: May 112000: Apr 162001: May 212002: May 92004: May 142005: May 122007: Apr 202009: May 22012: May 72013: May 52014: May 132015: May 112016: May 112017: May 32018: May 202019: May 242020: Apr 182021: May 222022: May 222023: Apr 282024: May 82025: May 7

First fall frost (32°F)

Aug 13Aug 28Sep 12Sep 27Oct 12Oct 27Nov 111970198019902000201020201964: Sep 271965: Sep 161966: Sep 301967: Oct 161968: Oct 81969: Oct 51970: Sep 131971: Sep 171972: Sep 241973: Oct 41974: Sep 21975: Sep 191976: Oct 71977: Oct 21978: Sep 201979: Oct 31980: Sep 161981: Oct 111982: Sep 141983: Sep 191984: Sep 81985: Sep 241986: Sep 221987: Oct 91988: Oct 31989: Sep 111990: Oct 31991: Sep 181993: Sep 141994: Oct 41995: Sep 211996: Sep 261997: Oct 81998: Oct 121999: Sep 272000: Sep 232001: Oct 52003: Sep 182004: Oct 112005: Oct 62006: Oct 42007: Sep 102008: Oct 102009: Oct 12011: Oct 72012: Oct 42013: Sep 272014: Sep 112015: Oct 242016: Oct 52017: Oct 32018: Sep 252019: Aug 312020: Sep 82022: Oct 162023: Oct 252024: Oct 192025: Oct 7

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

"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.