Last Frost Day

Frost history / Alyeska, AK

Alyeska, AK: frost dates by year

Last spring and first fall frost at NOAA station USC00500243, 1967 to 2025, measured from daily minimum temperatures.

Elevation 272 ft, 60.958, -149.111. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 13Sep 27
EarliestApr 18 (2005)Aug 27 (1984)
LatestJun 5 (1983)Oct 29 (2018)
Trend3.9 days earlier per decade4.7 days later per decade
Years with data4542

At 28°F (hard freeze) the median last spring date is Apr 24 and the median first fall date is Oct 4.

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 141970198019902000201020201968: Jun 31970: May 191971: May 281982: May 211983: Jun 51984: May 311985: May 211986: May 191987: May 111988: May 161990: May 231991: May 131992: May 181993: May 21994: May 91995: May 21996: May 41997: Apr 301998: May 161999: May 282000: May 212001: May 182002: May 172003: May 212004: Apr 272005: Apr 182006: May 12007: May 72008: May 182009: Apr 292010: May 92011: May 132013: May 222014: Apr 302015: Apr 252016: Apr 222017: May 262018: May 142019: Apr 292020: May 62021: May 52022: May 152023: May 62024: May 102025: May 10

First fall frost (32°F)

Aug 13Aug 28Sep 12Sep 27Oct 12Oct 27Nov 111970198019902000201020201967: Sep 41970: Sep 71981: Sep 221983: Sep 161984: Aug 271985: Sep 171986: Sep 241987: Sep 141988: Sep 241989: Oct 31990: Oct 21991: Oct 51992: Sep 111993: Sep 181994: Sep 271995: Oct 131996: Sep 221997: Oct 21998: Oct 11999: Sep 262000: Sep 92001: Sep 272002: Sep 202005: Oct 102006: Oct 12007: Oct 42008: Sep 282010: Sep 262011: Oct 42012: Sep 302013: Sep 212014: Oct 12015: Sep 192016: Oct 62017: Oct 102018: Oct 292019: Sep 262020: Oct 162021: Sep 222022: Oct 102023: Sep 262024: Oct 1

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

"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.