Last Frost Day

Frost history / Ellensburg, WA

Ellensburg, WA: frost dates by year

Last spring and first fall frost at NOAA station USC00452505, 1954 to 2025, measured from daily minimum temperatures.

Elevation 1,480 ft, 46.969, -120.540. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 7Sep 29
EarliestApr 6 (2016)Aug 22 (1960)
LatestJun 18 (1954)Oct 25 (2011)
Trend1.0 days earlier per decade2.5 days later per decade
Years with data6762

At 28°F (hard freeze) the median last spring date is Apr 21 and the median first fall date is Oct 11.

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 2919601970198019902000201020201954: Jun 181955: May 141956: Apr 301957: Apr 201958: May 141959: May 121960: Apr 251961: May 61962: May 51963: May 161964: May 231965: May 171966: Apr 191967: Apr 281968: May 21969: Apr 291970: May 141971: Apr 251972: May 11974: May 161975: May 41976: Apr 231977: May 61978: May 231979: Apr 251980: Jun 41982: May 301983: May 131984: Jun 21985: May 151986: May 151987: May 211988: May 171989: May 241990: Apr 301991: May 11992: May 121993: Apr 271994: May 31995: Apr 191996: May 111997: May 71998: Apr 201999: May 142000: May 102001: May 62002: May 82003: May 192004: Apr 252005: Apr 182006: May 102007: Apr 212009: May 12010: May 92011: May 172012: May 142015: May 72016: Apr 62017: May 152018: Apr 242019: May 12020: May 42021: Apr 262022: May 132023: Apr 252024: May 302025: May 5

First fall frost (32°F)

Aug 13Aug 28Sep 12Sep 27Oct 12Oct 27Nov 1119601970198019902000201020201954: Sep 291955: Sep 221956: Sep 221957: Sep 191958: Sep 241959: Oct 11960: Aug 221961: Sep 221962: Sep 121963: Oct 191964: Sep 271965: Sep 171966: Oct 91967: Sep 241968: Sep 191969: Sep 151970: Sep 91971: Sep 151974: Sep 291975: Sep 181976: Oct 151977: Oct 21978: Oct 21979: Oct 31981: Sep 211982: Sep 151983: Sep 191984: Sep 141985: Sep 281986: Sep 251987: Oct 91989: Oct 31990: Oct 61991: Oct 51992: Sep 71993: Sep 221994: Oct 51995: Sep 221996: Sep 221997: Oct 61998: Oct 101999: Sep 272000: Sep 232001: Oct 42002: Oct 12006: Oct 92007: Sep 292008: Sep 232009: Oct 62010: Oct 62011: Oct 252012: Oct 32013: Oct 32015: Sep 272016: Oct 122019: Sep 282020: Oct 222021: Oct 62022: Oct 192023: Sep 302024: Sep 302025: Oct 6

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 5Oct 6Apr 17Oct 14
2024May 30Sep 30Apr 23Oct 23
2023Apr 25Sep 30Apr 21Oct 28
2022May 13Oct 19Apr 20Oct 23
2021Apr 26Oct 6Apr 21Oct 8
2020May 4Oct 22Apr 17Oct 22
2019May 1Sep 28May 1Oct 6
2018Apr 24no dataApr 23no data
2017May 15no dataApr 16no data
2016Apr 6Oct 12Mar 19Oct 12
2015May 7Sep 27Apr 26Nov 4
2013no dataOct 3no dataOct 15
2012May 14Oct 3Apr 13Oct 5
2011May 17Oct 25May 1Oct 26
2010May 9Oct 6Apr 11Oct 17
2009May 1Oct 6Apr 24Oct 11
2008no dataSep 23no dataOct 11
2007Apr 21Sep 29Apr 20Oct 26
2006May 10Oct 9Apr 18Oct 22
2005Apr 18no dataApr 14no data
2004Apr 25no dataApr 19no data
2003May 19no dataApr 25no data
2002May 8Oct 1May 8Oct 11
2001May 6Oct 4Apr 14Oct 5
2000May 10Sep 23Apr 8Sep 23
1999May 14Sep 27May 10Sep 28
1998Apr 20Oct 10Apr 12Oct 19
1997May 7Oct 6May 1Oct 20
1996May 11Sep 22May 8Oct 16
1995Apr 19Sep 22Apr 19Oct 19
1994May 3Oct 5Mar 29Oct 24
1993Apr 27Sep 22Apr 20Oct 25
1992May 12Sep 7Apr 23Oct 15
1991May 1Oct 5Apr 26Oct 28
1990Apr 30Oct 6Mar 28Oct 7
1989May 24Oct 3Apr 9Oct 3
1988May 17no dataApr 10no data
1987May 21Oct 9Apr 20Oct 10
1986May 15Sep 25Apr 30Oct 11
1985May 15Sep 28May 12Sep 29
1984Jun 2Sep 14Apr 11Sep 28
1983May 13Sep 19Apr 16Sep 20
1982May 30Sep 15Apr 26Oct 18
1981no dataSep 21no dataOct 4
1980Jun 4no dataApr 11no data
1979Apr 25Oct 3Apr 21Oct 21
1978May 23Oct 2Apr 23Oct 6
1977May 6Oct 2Apr 17Oct 4
1976Apr 23Oct 15Apr 23Oct 17
1975May 4Sep 18Apr 11Oct 23
1974May 16Sep 29Apr 14Oct 5
1972May 1no dataMay 1no data
1971Apr 25Sep 15Apr 22Sep 29
1970May 14Sep 9May 11Sep 25
1969Apr 29Sep 15Apr 26Oct 4
1968May 2Sep 19Apr 22Oct 2
1967Apr 28Sep 24Apr 26Oct 18
1966Apr 19Oct 9Apr 19Oct 14
1965May 17Sep 17Apr 7Oct 16
1964May 23Sep 27May 23Oct 4
1963May 16Oct 19May 4Oct 19
1962May 5Sep 12May 4Oct 6
1961May 6Sep 22Apr 20Oct 8
1960Apr 25Aug 22Apr 24Oct 9
1959May 12Oct 1May 11Oct 10
1958May 14Sep 24Apr 18Sep 24
1957Apr 20Sep 19Apr 8Oct 15
1956Apr 30Sep 22Apr 6Oct 19
1955May 14Sep 22May 1Oct 6
1954Jun 18Sep 29May 1Oct 1

"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.