Last Frost Day

Frost history / Owyhee Dam, OR

Owyhee Dam, OR: frost dates by year

Last spring and first fall frost at NOAA station USC00356405, 1951 to 2024, measured from daily minimum temperatures.

Elevation 2,400 ft, 43.650, -117.247. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianApr 30Oct 13
EarliestMar 29 (2016)Sep 17 (1965)
LatestMay 23 (1966)Nov 6 (1962)
Trendlittle change (less than half a day per decade)0.8 days later per decade
Years with data6970

At 28°F (hard freeze) the median last spring date is Apr 10 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 16Mar 31Apr 15Apr 30May 15May 3019601970198019902000201020201951: Apr 221952: Apr 101953: Apr 151954: May 31955: Apr 271956: Apr 301957: Apr 251958: Apr 61959: May 41960: May 221961: Apr 201962: Apr 301963: Apr 211964: May 61965: May 181966: May 231967: May 11968: May 71969: May 31970: May 141971: Apr 131972: May 21973: May 121974: May 181975: Apr 301976: Apr 291977: Apr 201978: Apr 191979: Apr 201980: Apr 161981: Apr 151982: May 51983: May 131984: Apr 131985: Apr 241986: Apr 301987: May 201988: May 21989: Apr 261990: May 151991: Apr 281992: Apr 251993: Apr 161994: Apr 291995: Apr 171997: May 31998: Apr 182000: May 12002: May 102003: May 202004: Mar 302005: Apr 172006: Apr 202007: May 52009: May 142010: May 222011: May 182012: May 72013: May 22015: Apr 242016: Mar 292017: May 142018: Apr 252019: May 22020: May 62021: Apr 222022: May 112023: Apr 212024: May 1

First fall frost (32°F)

Sep 12Sep 27Oct 12Oct 27Nov 1119601970198019902000201020201951: Oct 171952: Oct 151953: Oct 31955: Oct 61956: Oct 141957: Oct 191958: Sep 241959: Oct 181960: Oct 131961: Oct 211962: Nov 61963: Oct 261964: Oct 41965: Sep 171966: Oct 101967: Oct 151968: Oct 31969: Oct 51970: Sep 251971: Sep 181972: Sep 261973: Oct 41974: Oct 61975: Oct 241976: Oct 181977: Oct 131978: Oct 141979: Oct 301980: Oct 191981: Oct 41982: Oct 191983: Sep 201984: Sep 251985: Sep 291986: Oct 111987: Sep 271988: Oct 311989: Oct 161990: Oct 71991: Oct 61992: Nov 31993: Sep 221994: Oct 221997: Oct 141998: Oct 171999: Sep 282000: Sep 252001: Oct 102002: Oct 122003: Oct 302004: Oct 202005: Oct 62006: Oct 112007: Sep 302008: Oct 92009: Oct 12010: Oct 132011: Oct 262012: Oct 42013: Oct 152014: Oct 282015: Nov 52016: Oct 122017: Sep 242018: Oct 142019: Sep 302020: Oct 232021: Oct 152022: Oct 252023: Oct 27

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 1no dataMar 16no data
2023Apr 21Oct 27Apr 20Oct 27
2022May 11Oct 25May 4Nov 3
2021Apr 22Oct 15Apr 2Nov 8
2020May 6Oct 23Apr 5Oct 23
2019May 2Sep 30May 2Oct 1
2018Apr 25Oct 14Apr 4Oct 15
2017May 14Sep 24Apr 16Oct 14
2016Mar 29Oct 12Mar 29Nov 17
2015Apr 24Nov 5Apr 13Nov 5
2014no dataOct 28no dataNov 11
2013May 2Oct 15May 2Nov 5
2012May 7Oct 4Apr 7Oct 5
2011May 18Oct 26Apr 23Oct 26
2010May 22Oct 13May 8Nov 9
2009May 14Oct 1May 14Oct 6
2008no dataOct 9no dataOct 22
2007May 5Sep 30May 5Oct 27
2006Apr 20Oct 11Mar 28Oct 22
2005Apr 17Oct 6Apr 16Nov 9
2004Mar 30Oct 20Mar 29Oct 25
2003May 20Oct 30May 20Oct 31
2002May 10Oct 12May 9Oct 12
2001no dataOct 10no dataOct 26
2000May 1Sep 25Apr 10Oct 23
1999no dataSep 28no dataOct 17
1998Apr 18Oct 17Mar 21Oct 30
1997May 3Oct 14Apr 11Oct 25
1995Apr 17no dataApr 16no data
1994Apr 29Oct 22Apr 5Oct 29
1993Apr 16Sep 22Mar 13Sep 22
1992Apr 25Nov 3Apr 8Nov 10
1991Apr 28Oct 6Apr 11Oct 30
1990May 15Oct 7Mar 26Oct 17
1989Apr 26Oct 16Mar 5Oct 29
1988May 2Oct 31May 2Nov 7
1987May 20Sep 27May 20Oct 10
1986Apr 30Oct 11Feb 20Oct 11
1985Apr 24Sep 29Mar 26Sep 30
1984Apr 13Sep 25Mar 8Sep 25
1983May 13Sep 20Apr 5Sep 21
1982May 5Oct 19Apr 22Oct 19
1981Apr 15Oct 4Apr 15Oct 5
1980Apr 16Oct 19Apr 11Oct 23
1979Apr 20Oct 30Mar 15Nov 2
1978Apr 19Oct 14Mar 17Oct 23
1977Apr 20Oct 13Apr 2Nov 3
1976Apr 29Oct 18Apr 3Oct 18
1975Apr 30Oct 24Apr 4Oct 24
1974May 18Oct 6Mar 25Oct 7
1973May 12Oct 4Mar 18Oct 4
1972May 2Sep 26May 1Oct 27
1971Apr 13Sep 18Apr 8Oct 15
1970May 14Sep 25Apr 21Oct 15
1969May 3Oct 5Apr 26Oct 13
1968May 7Oct 3Apr 20Oct 9
1967May 1Oct 15Apr 22Oct 20
1966May 23Oct 10Apr 28Oct 14
1965May 18Sep 17Mar 29Sep 18
1964May 6Oct 4Apr 23Oct 17
1963Apr 21Oct 26Apr 21Oct 26
1962Apr 30Nov 6Apr 30Nov 7
1961Apr 20Oct 21Apr 20Nov 2
1960May 22Oct 13Apr 25Oct 13
1959May 4Oct 18Mar 21Nov 5
1958Apr 6Sep 24Mar 28Oct 21
1957Apr 25Oct 19Mar 27Nov 3
1956Apr 30Oct 14Apr 8Oct 27
1955Apr 27Oct 6Apr 6Oct 6
1954May 3no dataApr 11no data
1953Apr 15Oct 3Apr 15Nov 9
1952Apr 10Oct 15Apr 9Oct 16
1951Apr 22Oct 17Mar 28Oct 29

"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.