Last Frost Day

Frost history / Petersburg 1, AK

Petersburg 1, AK: frost dates by year

Last spring and first fall frost at NOAA station USW00025329, 1951 to 2024, measured from daily minimum temperatures.

Elevation 107 ft, 56.806, -132.937. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 11Oct 6
EarliestApr 9 (2016)Sep 5 (1992)
LatestJun 16 (1967)Nov 11 (2014)
Trend3.2 days earlier per decade1.4 days later per decade
Years with data5958

At 28°F (hard freeze) the median last spring date is Apr 16 and the median first fall date is Oct 23.

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 2919601970198019902000201020201951: May 271952: Jun 71953: Apr 241954: May 151955: May 221956: May 291957: May 101958: Apr 271959: May 121960: May 91961: May 101962: May 151963: Jun 71964: May 241965: May 201966: May 291967: Jun 161968: May 141969: May 161970: May 111971: May 171972: May 241973: May 231974: May 301975: May 251976: Apr 301977: May 111981: Apr 181984: May 31985: May 111987: Apr 251988: May 51989: May 181990: May 201991: Apr 201992: May 191993: Apr 241994: May 151995: Apr 282001: May 62004: Apr 232006: May 132007: May 172008: Apr 292009: May 52010: May 42011: Apr 282012: May 142013: Apr 302014: Apr 252015: May 32016: Apr 92018: Apr 292019: Apr 292020: Apr 192021: May 192022: Apr 292023: May 42024: May 3

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 11Nov 2619601970198019902000201020201951: Sep 251952: Nov 51953: Oct 231954: Oct 21955: Sep 211956: Sep 261957: Oct 21958: Sep 221959: Oct 51960: Nov 21961: Sep 261962: Oct 231963: Oct 51964: Sep 81965: Sep 261966: Oct 121967: Nov 11968: Oct 71969: Oct 131970: Sep 111972: Sep 221973: Sep 131974: Oct 31976: Oct 151977: Sep 241983: Sep 261984: Oct 171985: Sep 271986: Oct 111987: Oct 71988: Sep 271989: Oct 111990: Oct 31991: Oct 161992: Sep 51993: Oct 71994: Sep 291995: Oct 152004: Oct 172005: Oct 32006: Sep 152007: Oct 192008: Oct 92009: Sep 292010: Nov 92011: Oct 22012: Oct 22014: Nov 112015: Oct 262016: Oct 92017: Oct 132018: Oct 22019: Oct 82020: Oct 132021: Oct 42022: Oct 222023: Oct 222024: Oct 20

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
2024May 3Oct 20Apr 1Oct 21
2023May 4Oct 22Apr 4Oct 23
2022Apr 29Oct 22Apr 17Nov 1
2021May 19Oct 4Apr 12Oct 6
2020Apr 19Oct 13Apr 12Oct 22
2019Apr 29Oct 8Mar 8Nov 25
2018Apr 29Oct 2Apr 5Oct 4
2017no dataOct 13no dataNov 2
2016Apr 9Oct 9Mar 3Oct 11
2015May 3Oct 26Apr 22Nov 18
2014Apr 25Nov 11Apr 13Nov 12
2013Apr 30no dataApr 30no data
2012May 14Oct 2Apr 8Oct 19
2011Apr 28Oct 2Apr 20Nov 3
2010May 4Nov 9Apr 14Nov 9
2009May 5Sep 29Apr 23Oct 13
2008Apr 29Oct 9Apr 25Nov 9
2007May 17Oct 19Apr 18Nov 29
2006May 13Sep 15Apr 16Oct 29
2005no dataOct 3no dataOct 15
2004Apr 23Oct 17Apr 16Oct 19
2001May 6no dataMay 6no data
1995Apr 28Oct 15Apr 15Oct 29
1994May 15Sep 29Apr 18Oct 31
1993Apr 24Oct 7Mar 28Nov 4
1992May 19Sep 5Apr 13Sep 13
1991Apr 20Oct 16Apr 3Oct 24
1990May 20Oct 3Apr 10Oct 5
1989May 18Oct 11May 18Oct 16
1988May 5Sep 27Apr 20Nov 24
1987Apr 25Oct 7Apr 6Oct 30
1986no dataOct 11no dataOct 30
1985May 11Sep 27Apr 15Nov 2
1984May 3Oct 17Feb 24Oct 20
1983no dataSep 26no dataOct 15
1981Apr 18no dataApr 12no data
1977May 11Sep 24Mar 24Oct 3
1976Apr 30Oct 15Apr 22Nov 28
1975May 25no dataApr 25no data
1974May 30Oct 3Apr 15Nov 12
1973May 23Sep 13Apr 14Oct 17
1972May 24Sep 22May 8Sep 22
1971May 17no dataApr 25no data
1970May 11Sep 11Mar 11Nov 6
1969May 16Oct 13Apr 13Oct 24
1968May 14Oct 7May 4Oct 11
1967Jun 16Nov 1May 10Nov 3
1966May 29Oct 12May 10Oct 21
1965May 20Sep 26Apr 30Nov 5
1964May 24Sep 8May 13Oct 29
1963Jun 7Oct 5Apr 25Oct 6
1962May 15Oct 23May 4Oct 23
1961May 10Sep 26Apr 13Oct 20
1960May 9Nov 2Apr 14Nov 7
1959May 12Oct 5Apr 29Oct 6
1958Apr 27Sep 22Apr 24Oct 5
1957May 10Oct 2May 6Oct 3
1956May 29Sep 26May 5Sep 26
1955May 22Sep 21Apr 28Oct 22
1954May 15Oct 2May 1Oct 4
1953Apr 24Oct 23Apr 13Oct 23
1952Jun 7Nov 5Apr 6Nov 14
1951May 27Sep 25Apr 23Oct 17

"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.