Last Frost Day

Frost history / Shoshone 1 Wnw, ID

Shoshone 1 Wnw, ID: frost dates by year

Last spring and first fall frost at NOAA station USC00108380, 1951 to 2025, measured from daily minimum temperatures.

Elevation 3,950 ft, 42.938, -114.417. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 18Sep 30
EarliestMar 18 (2019)Aug 23 (1960)
LatestJun 29 (1970)Oct 28 (2025)
Trend3.0 days earlier per decade2.7 days later per decade
Years with data6066

At 28°F (hard freeze) the median last spring date is May 2 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 1Mar 16Mar 31Apr 15Apr 30May 15May 30Jun 14Jun 29Jul 1419601970198019902000201020201951: May 141952: Apr 161953: May 251954: Jun 61955: May 281956: May 141959: May 191960: May 251961: May 191962: Apr 301963: Apr 241964: May 221965: May 181966: May 231967: May 131968: Jun 11970: Jun 291971: May 201973: May 261975: May 251976: Jun 141977: May 181978: May 261980: Apr 161981: May 91982: Jun 61983: May 131984: May 231986: May 231987: May 31988: May 71990: Jun 131991: May 191992: Apr 241993: Jun 31994: Apr 291995: Jun 71996: May 101998: May 271999: May 172000: May 122002: Jun 92003: May 192004: Apr 302006: May 102008: May 22010: May 252011: Jun 32012: May 112013: May 22014: May 22017: Apr 282018: Apr 182019: Mar 182020: May 62021: Apr 202022: May 192023: Apr 202024: May 22025: Apr 19

First fall frost (32°F)

Aug 13Aug 28Sep 12Sep 27Oct 12Oct 27Nov 1119601970198019902000201020201951: Oct 61952: Oct 141953: Oct 31954: Sep 291956: Sep 221958: Sep 241959: Sep 281960: Aug 231961: Sep 211962: Sep 301963: Oct 131964: Sep 191965: Sep 161966: Oct 41967: Sep 131968: Sep 211969: Oct 31970: Sep 91971: Sep 151973: Sep 261974: Oct 51975: Oct 81976: Sep 71977: Sep 231978: Sep 171979: Oct 211980: Sep 221981: Sep 261982: Sep 111983: Sep 111984: Sep 221985: Sep 191986: Sep 161987: Sep 171988: Sep 181989: Oct 161990: Oct 71991: Oct 61992: Oct 61993: Sep 211994: Oct 151995: Sep 301998: Oct 51999: Sep 272000: Sep 242001: Oct 92002: Sep 302003: Sep 182004: Sep 212006: Sep 172009: Oct 12010: Oct 122011: Oct 252012: Oct 42013: Oct 42014: Sep 12016: Oct 112017: Oct 92018: Oct 122019: Oct 42020: Oct 222021: Oct 122022: Oct 232023: Oct 272024: Oct 182025: Oct 28

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
2025Apr 19Oct 28Apr 2Oct 28
2024May 2Oct 18Apr 30Oct 18
2023Apr 20Oct 27Apr 20Oct 28
2022May 19Oct 23Apr 5Oct 24
2021Apr 20Oct 12Apr 12Nov 16
2020May 6Oct 22Apr 14Oct 25
2019Mar 18Oct 4Mar 16Oct 9
2018Apr 18Oct 12Apr 3Oct 14
2017Apr 28Oct 9Apr 20Oct 31
2016no dataOct 11no dataNov 16
2014May 2Sep 1Apr 29Sep 4
2013May 2Oct 4May 2Oct 5
2012May 11Oct 4May 6Oct 18
2011Jun 3Oct 25May 2Oct 25
2010May 25Oct 12May 7Oct 27
2009no dataOct 1no dataOct 1
2008May 2no dataMay 2no data
2006May 10Sep 17Apr 19Oct 18
2004Apr 30Sep 21Mar 29Oct 31
2003May 19Sep 18Apr 6Oct 11
2002Jun 9Sep 30May 9Oct 3
2001no dataOct 9no dataOct 10
2000May 12Sep 24May 12Sep 24
1999May 17Sep 27May 10Sep 27
1998May 27Oct 5May 18Oct 5
1996May 10no dataApr 21no data
1995Jun 7Sep 30Apr 20Oct 1
1994Apr 29Oct 15Apr 15Oct 17
1993Jun 3Sep 21Apr 27Oct 26
1992Apr 24Oct 6Apr 24Oct 6
1991May 19Oct 6Apr 30Oct 6
1990Jun 13Oct 7May 9Oct 7
1989no dataOct 16no dataOct 16
1988May 7Sep 18May 2Oct 27
1987May 3Sep 17Apr 20Sep 27
1986May 23Sep 16Apr 30Sep 28
1985no dataSep 19no dataSep 29
1984May 23Sep 22May 7Sep 24
1983May 13Sep 11Apr 25Sep 20
1982Jun 6Sep 11Jun 6Oct 9
1981May 9Sep 26May 7Oct 4
1980Apr 16Sep 22Apr 11Oct 18
1979no dataOct 21no dataOct 29
1978May 26Sep 17May 5Oct 22
1977May 18Sep 23Apr 20Sep 23
1976Jun 14Sep 7Apr 21Oct 5
1975May 25Oct 8May 25Oct 22
1974no dataOct 5no dataOct 6
1973May 26Sep 26May 26Oct 3
1971May 20Sep 15May 18Sep 27
1970Jun 29Sep 9May 14Sep 14
1969no dataOct 3no dataOct 4
1968Jun 1Sep 21May 8Oct 8
1967May 13Sep 13May 13Oct 15
1966May 23Oct 4May 23Oct 9
1965May 18Sep 16May 7Sep 17
1964May 22Sep 19May 11Oct 17
1963Apr 24Oct 13Apr 24Oct 24
1962Apr 30Sep 30Apr 30Oct 6
1961May 19Sep 21May 13Sep 21
1960May 25Aug 23May 19Oct 9
1959May 19Sep 28May 16Oct 8
1958no dataSep 24no dataOct 21
1956May 14Sep 22May 14Sep 22
1955May 28no dataMay 27no data
1954Jun 6Sep 29May 28Sep 29
1953May 25Oct 3May 11Oct 25
1952Apr 16Oct 14Apr 12Oct 16
1951May 14Oct 6Apr 22Oct 16

"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.