Last Frost Day

Frost history / Sedro-Woolley, WA

Sedro-Woolley, WA: frost dates by year

Last spring and first fall frost at NOAA station USC00457507, 1951 to 2025, measured from daily minimum temperatures.

Elevation 60 ft, 48.496, -122.236. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianApr 10Oct 30
EarliestFeb 19 (1981)Sep 27 (1972)
LatestMay 19 (2011)Dec 25 (2001)
Trend4.0 days earlier per decade2.7 days later per decade
Years with data6667

At 28°F (hard freeze) the median last spring date is Mar 6 and the median first fall date is Nov 20.

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)

Feb 14Mar 1Mar 16Mar 31Apr 15Apr 30May 15May 3019601970198019902000201020201951: May 11952: May 51953: Apr 101954: May 11955: May 61956: Apr 301957: Apr 91958: May 131959: Apr 71960: Apr 221961: Apr 201962: May 71963: Apr 21964: May 151965: May 71966: Apr 121967: Apr 111968: Apr 221969: Apr 151970: Apr 151971: Apr 171972: Apr 221973: Apr 301974: Mar 231975: Apr 141977: Mar 301978: Mar 121979: Mar 201980: Mar 61981: Feb 191983: Apr 121984: Mar 61985: Apr 211986: Apr 101987: Feb 251988: Mar 141989: Mar 231990: Mar 271991: Mar 271992: Apr 71993: Mar 271994: Mar 251996: Mar 281997: Apr 41999: May 102000: Mar 82001: Apr 112002: May 72003: Mar 12004: Apr 12005: Feb 282006: Mar 192007: Mar 232008: Apr 212010: Apr 102011: May 192014: Apr 22017: Mar 192018: Mar 262019: Mar 192020: Apr 252021: Mar 172022: Mar 102023: Apr 172024: Apr 172025: Mar 7

First fall frost (32°F)

Sep 12Sep 27Oct 12Oct 27Nov 11Nov 26Dec 11Dec 26Jan 1019601970198019902000201020201951: Oct 261952: Oct 141953: Oct 221954: Oct 241955: Nov 11956: Oct 281957: Oct 151958: Oct 271959: Oct 291960: Oct 91961: Oct 181962: Oct 141963: Nov 191965: Nov 231966: Oct 151967: Nov 31968: Nov 41969: Oct 131970: Oct 261971: Oct 161972: Sep 271973: Nov 11974: Oct 241975: Oct 251976: Oct 191977: Nov 171978: Nov 91979: Nov 81980: Nov 161981: Oct 211982: Nov 31983: Nov 291984: Oct 161985: Oct 81986: Nov 91987: Oct 191988: Oct 281989: Nov 11990: Nov 201991: Oct 281992: Nov 231993: Nov 81994: Nov 31996: Oct 261997: Nov 121998: Oct 191999: Oct 22000: Nov 112001: Dec 252002: Oct 302003: Oct 302004: Nov 202005: Nov 242006: Oct 252007: Nov 22008: Oct 102009: Dec 22010: Nov 212016: Dec 62017: Nov 32018: Nov 112019: Oct 92020: Oct 242022: Nov 32023: Oct 262024: Nov 162025: Nov 30

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
2025Mar 7Nov 30Feb 14Nov 30
2024Apr 17Nov 16Mar 8Dec 3
2023Apr 17Oct 26Apr 15Oct 27
2022Mar 10Nov 3Feb 25Nov 9
2021Mar 17no dataMar 16no data
2020Apr 25Oct 24Mar 16Dec 25
2019Mar 19Oct 9Mar 10Oct 29
2018Mar 26Nov 11Feb 24Dec 5
2017Mar 19Nov 3Feb 9Dec 6
2016no dataDec 6no dataDec 6
2014Apr 2no dataMar 12no data
2011May 19no dataMar 7no data
2010Apr 10Nov 21Mar 9Nov 22
2009no dataDec 2no dataDec 3
2008Apr 21Oct 10Mar 5Dec 14
2007Mar 23Nov 2Mar 2Nov 22
2006Mar 19Oct 25Mar 11Oct 25
2005Feb 28Nov 24Feb 18Dec 11
2004Apr 1Nov 20Jan 7Nov 28
2003Mar 1Oct 30Feb 27Nov 1
2002May 7Oct 30Mar 21Nov 2
2001Apr 11Dec 25Feb 14Dec 25
2000Mar 8Nov 11Mar 6Nov 11
1999May 10Oct 2Apr 5Dec 22
1998no dataOct 19no dataNov 8
1997Apr 4Nov 12Feb 26Dec 6
1996Mar 28Oct 26Mar 25Nov 19
1994Mar 25Nov 3Feb 9Nov 18
1993Mar 27Nov 8Feb 28Nov 11
1992Apr 7Nov 23Feb 6Dec 4
1991Mar 27Oct 28Mar 5Oct 29
1990Mar 27Nov 20Feb 19Dec 16
1989Mar 23Nov 1Mar 4Dec 12
1988Mar 14Oct 28Feb 2Dec 16
1987Feb 25Oct 19Jan 17Dec 13
1986Apr 10Nov 9Feb 20Dec 7
1985Apr 21Oct 8Mar 11Nov 11
1984Mar 6Oct 16Jan 28Nov 1
1983Apr 12Nov 29Feb 5Dec 1
1982no dataNov 3no dataNov 11
1981Feb 19Oct 21Feb 12none
1980Mar 6Nov 16Feb 14Dec 5
1979Mar 20Nov 8Feb 17Nov 12
1978Mar 12Nov 9Mar 3Nov 11
1977Mar 30Nov 17Mar 16Nov 18
1976no dataOct 19no dataNov 26
1975Apr 14Oct 25Mar 6Nov 18
1974Mar 23Oct 24Mar 8none
1973Apr 30Nov 1Feb 20Nov 30
1972Apr 22Sep 27Feb 5Nov 17
1971Apr 17Oct 16Mar 21Oct 27
1970Apr 15Oct 26Mar 6Oct 30
1969Apr 15Oct 13Mar 13Nov 27
1968Apr 22Nov 4Mar 11Dec 19
1967Apr 11Nov 3Mar 13Nov 21
1966Apr 12Oct 15Mar 2Nov 8
1965May 7Nov 23Mar 24Dec 13
1964May 15no dataMar 24no data
1963Apr 2Nov 19Mar 10Nov 20
1962May 7Oct 14Mar 12Dec 12
1961Apr 20Oct 18Mar 4Nov 4
1960Apr 22Oct 9Mar 19Dec 5
1959Apr 7Oct 29Feb 12Nov 4
1958May 13Oct 27Mar 11Nov 15
1957Apr 9Oct 15Feb 28Oct 20
1956Apr 30Oct 28Mar 17Oct 28
1955May 6Nov 1Mar 26Nov 11
1954May 1Oct 24Apr 30Oct 24
1953Apr 10Oct 22Apr 1none
1952May 5Oct 14Apr 8Nov 8
1951May 1Oct 26Apr 21Oct 30

"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.