Last Frost Day

Frost history / Vacaville, CA

Vacaville, CA: frost dates by year

Last spring and first fall frost at NOAA station USC00049200, 1951 to 2008, measured from daily minimum temperatures.

Elevation 110 ft, 38.396, -121.961. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMar 14Nov 24
EarliestJan 12 (2005)Oct 24 (1956)
LatestMay 18 (1974)Dec 28 (2003)
Trend5.3 days earlier per decade4.4 days later per decade
Years with data52, 1 with no freeze49, 3 with no freeze

At 28°F (hard freeze) the median last spring date is Jan 21 and the median first fall date is Dec 8.

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)

Dec 31Jan 15Jan 30Feb 14Mar 1Mar 16Mar 31Apr 15Apr 30May 15May 30196019701980199020001951: Mar 111952: Mar 201953: Apr 81954: Mar 141955: Apr 31956: Mar 71957: Mar 181958: Mar 171959: Feb 131960: Feb 271961: Mar 71962: Mar 131963: Apr 211964: Apr 241965: Feb 121966: Mar 41967: Apr 291968: Jan 281969: Mar 141970: Apr 281971: Mar 81972: Apr 231973: Mar 221974: May 181975: Apr 171976: Apr 21977: Mar 141979: Mar 21981: Mar 31982: Apr 61983: Jan 201984: Feb 231987: Mar 261989: Feb 281991: Mar 271992: Jan 141993: Feb 271994: Mar 231995: Feb 151996: Feb 281997: Jan 141999: Apr 102000: Mar 212001: Apr 82002: Mar 192003: Feb 102004: Jan 232005: Jan 122006: Mar 282007: Feb 192008: Feb 13

First fall frost (32°F)

Oct 12Oct 27Nov 11Nov 26Dec 11Dec 26Jan 10196019701980199020001951: Nov 231952: Nov 21953: Nov 191954: Nov 301955: Oct 311956: Oct 241957: Nov 51958: Nov 171959: Nov 151960: Nov 281961: Nov 171962: Nov 301963: Nov 211964: Nov 141965: Nov 261966: Nov 241967: Nov 261968: Nov 271969: Nov 181970: Dec 121971: Oct 301972: Nov 231973: Nov 31974: Nov 271975: Nov 211976: Nov 291977: Nov 191979: Nov 211981: Nov 301982: Nov 131983: Nov 221984: Dec 161986: Nov 261987: Nov 271990: Nov 11991: Nov 281992: Nov 281993: Nov 141996: Dec 31997: Dec 121999: Dec 152000: Nov 122003: Dec 282004: Nov 302006: Dec 172007: Dec 12

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
2008Feb 13no datanoneno data
2007Feb 19Dec 12Jan 16none
2006Mar 28Dec 17nonenone
2005Jan 12no datanoneno data
2004Jan 23Nov 30Jan 4none
2003Feb 10Dec 28nonenone
2002Mar 19noneJan 31none
2001Apr 8noneFeb 13none
2000Mar 21Nov 12nonenone
1999Apr 10Dec 15Jan 12none
1998noneno datanoneno data
1997Jan 14Dec 12Jan 14none
1996Feb 28Dec 3noneDec 19
1995Feb 15nonenonenone
1994Mar 23no dataJan 27no data
1993Feb 27Nov 14Jan 11Dec 17
1992Jan 14Nov 28Jan 8Dec 5
1991Mar 27Nov 28Jan 2Nov 28
1990no dataNov 1no dataDec 20
1989Feb 28no dataFeb 7no data
1987Mar 26Nov 27Jan 18Dec 31
1986no dataNov 26no datanone
1984Feb 23Dec 16Jan 18Dec 22
1983Jan 20Nov 22nonenone
1982Apr 6Nov 13Jan 27none
1981Mar 3Nov 30nonenone
1979Mar 2Nov 21Feb 4Nov 22
1977Mar 14Nov 19Jan 9Nov 19
1976Apr 2Nov 29Mar 5Nov 29
1975Apr 17Nov 21Jan 31Dec 2
1974May 18Nov 27Jan 10Dec 25
1973Mar 22Nov 3Jan 7none
1972Apr 23Nov 23Jan 24Dec 5
1971Mar 8Oct 30Mar 6Dec 10
1970Apr 28Dec 12Jan 6Dec 25
1969Mar 14Nov 18Jan 31Nov 29
1968Jan 28Nov 27Jan 6Dec 3
1967Apr 29Nov 26Jan 17Dec 12
1966Mar 4Nov 24Mar 3Dec 26
1965Feb 12Nov 26Jan 1Dec 15
1964Apr 24Nov 14Jan 16Nov 19
1963Apr 21Nov 21Jan 25Dec 11
1962Mar 13Nov 30Jan 25Dec 26
1961Mar 7Nov 17Jan 21Nov 17
1960Feb 27Nov 28Jan 17Dec 8
1959Feb 13Nov 15Jan 4Dec 7
1958Mar 17Nov 17Jan 22Nov 17
1957Mar 18Nov 5Feb 5none
1956Mar 7Oct 24Mar 6Dec 7
1955Apr 3Oct 31Mar 1none
1954Mar 14Nov 30Jan 25Nov 30
1953Apr 8Nov 19noneDec 23
1952Mar 20Nov 2Jan 19Nov 25
1951Mar 11Nov 23Feb 1Dec 9

"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.