Last Frost Day

Frost history / Prosser, WA

Prosser, WA: frost dates by year

Last spring and first fall frost at NOAA station USC00456768, 1951 to 2023, measured from daily minimum temperatures.

Elevation 830 ft, 46.201, -119.758. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianApr 28Oct 15
EarliestFeb 26 (2004)Sep 15 (1970)
LatestMay 31 (1955)Nov 17 (2016)
Trend5.7 days earlier per decade2.4 days later per decade
Years with data5362

At 28°F (hard freeze) the median last spring date is Apr 9 and the median first fall date is Oct 31.

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 30Jun 1419601970198019902000201020201951: May 291952: May 41953: May 121954: May 21955: May 311956: Apr 81957: Apr 251958: Apr 231959: May 111960: May 221961: May 61962: May 41963: Apr 161965: May 51966: Apr 191967: Apr 281968: May 51969: Apr 261970: May 111971: May 171972: May 11973: Apr 291974: May 161975: May 191976: Apr 251977: May 61978: May 41979: Apr 201980: Apr 111981: May 61982: May 51983: Apr 251985: May 121988: Apr 301990: Mar 291991: May 91997: Apr 121999: May 92000: Apr 292001: Apr 162002: Apr 42003: Apr 42004: Feb 262005: Apr 152006: Mar 162007: Apr 42008: Apr 222016: Mar 282017: Apr 122018: Apr 52019: Mar 212020: Apr 52023: Apr 21

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 11Nov 2619601970198019902000201020201951: Oct 151952: Oct 151953: Oct 241954: Oct 11955: Oct 61956: Oct 221957: Nov 41958: Oct 201959: Oct 71960: Oct 91961: Oct 181962: Nov 71963: Oct 191964: Oct 31965: Sep 171966: Oct 131967: Oct 201968: Oct 21969: Oct 131970: Sep 151971: Sep 181972: Sep 251973: Oct 21974: Sep 271975: Oct 221976: Oct 151977: Oct 41978: Oct 131979: Nov 11980: Oct 171981: Oct 31982: Oct 181983: Sep 201984: Sep 281985: Sep 291986: Nov 21987: Oct 151988: Oct 271991: Oct 171992: Oct 71993: Oct 201997: Oct 131999: Sep 282000: Sep 232001: Sep 292002: Oct 252003: Oct 312004: Oct 262005: Oct 282006: Oct 312007: Oct 272009: Oct 102010: Nov 92011: Oct 262012: Oct 152013: Oct 282016: Nov 172018: Nov 82019: Oct 22020: Oct 232021: Nov 22022: Nov 3

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
2023Apr 21no dataMar 28no data
2022no dataNov 3no dataNov 10
2021no dataNov 2no dataNov 17
2020Apr 5Oct 23Apr 4Oct 25
2019Mar 21Oct 2Mar 20Oct 10
2018Apr 5Nov 8Mar 10Nov 8
2017Apr 12no dataMar 1no data
2016Mar 28Nov 17Mar 18Nov 18
2013no dataOct 28no dataNov 15
2012no dataOct 15no dataNov 10
2011no dataOct 26no dataNov 2
2010no dataNov 9no dataNov 20
2009no dataOct 10no dataOct 10
2008Apr 22no dataApr 2no data
2007Apr 4Oct 27Mar 2Oct 27
2006Mar 16Oct 31Mar 14Oct 31
2005Apr 15Oct 28Feb 26Nov 8
2004Feb 26Oct 26Feb 22Nov 4
2003Apr 4Oct 31Feb 27Oct 31
2002Apr 4Oct 25Apr 3Oct 26
2001Apr 16Sep 29Apr 14Oct 6
2000Apr 29Sep 23Apr 29Sep 23
1999May 9Sep 28May 8Oct 10
1997Apr 12Oct 13Apr 4Nov 12
1993no dataOct 20no dataNov 1
1992no dataOct 7no dataOct 15
1991May 9Oct 17Apr 26Oct 29
1990Mar 29no dataMar 27no data
1988Apr 30Oct 27Apr 9Oct 28
1987no dataOct 15no dataNov 17
1986no dataNov 2no dataNov 8
1985May 12Sep 29Apr 25Oct 8
1984no dataSep 28no dataOct 18
1983Apr 25Sep 20Apr 12Nov 28
1982May 5Oct 18Apr 20Oct 18
1981May 6Oct 3Apr 13Oct 14
1980Apr 11Oct 17Apr 11Oct 22
1979Apr 20Nov 1Apr 10Nov 1
1978May 4Oct 13Mar 15Oct 22
1977May 6Oct 4Apr 17Nov 3
1976Apr 25Oct 15Apr 25Oct 18
1975May 19Oct 22Apr 8Oct 23
1974May 16Sep 27Mar 21Oct 6
1973Apr 29Oct 2Apr 8Nov 1
1972May 1Sep 25Apr 30Oct 27
1971May 17Sep 18Apr 24Oct 17
1970May 11Sep 15Apr 27Oct 16
1969Apr 26Oct 13Apr 26Oct 13
1968May 5Oct 2Apr 17Oct 31
1967Apr 28Oct 20Apr 14Nov 3
1966Apr 19Oct 13Apr 19Nov 11
1965May 5Sep 17Mar 25Nov 25
1964no dataOct 3no dataOct 26
1963Apr 16Oct 19Apr 2Oct 26
1962May 4Nov 7Mar 29Nov 23
1961May 6Oct 18Apr 19Oct 20
1960May 22Oct 9Apr 22Nov 4
1959May 11Oct 7Apr 14Oct 30
1958Apr 23Oct 20Mar 12Oct 21
1957Apr 25Nov 4Mar 26Nov 4
1956Apr 8Oct 22Apr 6Oct 24
1955May 31Oct 6Apr 27Oct 31
1954May 2Oct 1May 1Oct 1
1953May 12Oct 24Apr 2Nov 2
1952May 4Oct 15Apr 29Nov 1
1951May 29Oct 15Apr 21Oct 31

"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.