Last Frost Day

Frost history / Riddle, OR

Riddle, OR: frost dates by year

Last spring and first fall frost at NOAA station USC00357169, 1951 to 2025, measured from daily minimum temperatures.

Elevation 680 ft, 42.951, -123.357. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianApr 17Nov 1
EarliestJan 11 (2016)Sep 14 (1970)
LatestMay 25 (1975)Dec 22 (1953)
Trend3.3 days earlier per decade1.8 days later per decade
Years with data7471

At 28°F (hard freeze) the median last spring date is Mar 6 and the median first fall date is Nov 22.

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 3019601970198019902000201020201951: Apr 211952: May 51953: Apr 121954: May 221955: Apr 151956: Apr 301957: Apr 151958: May 131959: May 41960: Apr 241961: Apr 271962: Apr 111963: Apr 201964: May 21965: May 171966: Apr 291967: Apr 221968: May 71969: Apr 301970: Apr 171971: Apr 211972: Apr 301973: Apr 71974: Apr 251975: May 251976: Apr 91977: Apr 201978: Apr 71980: Apr 31981: Apr 61982: May 131983: Apr 151984: May 61985: May 81986: Apr 241987: Mar 301988: Mar 311989: Mar 261990: Mar 151991: Mar 301992: Apr 221993: Feb 281994: Apr 41995: Mar 281996: Mar 281997: Apr 61998: Mar 301999: May 92000: Mar 312001: Apr 52002: May 82003: Feb 282004: Apr 22005: Apr 132006: Mar 202007: Mar 292008: Apr 232009: Apr 252010: May 62011: May 12012: Mar 192013: May 12014: Apr 132015: Apr 32016: Jan 112017: Apr 102018: Apr 32019: May 22020: Apr 172021: Apr 272022: Apr 152023: Apr 182024: Apr 222025: Apr 15

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 11Nov 26Dec 11Dec 26Jan 1019601970198019902000201020201951: Nov 161952: Nov 31953: Dec 221954: Oct 241955: Nov 121956: Nov 141957: Nov 11958: Nov 151959: Oct 11960: Nov 41961: Oct 201963: Dec 21964: Oct 211965: Sep 171966: Oct 191967: Nov 201968: Oct 91969: Oct 131970: Sep 141971: Oct 171972: Sep 271973: Oct 31974: Oct 51975: Nov 181976: Oct 181977: Nov 81978: Nov 11979: Nov 211980: Nov 131982: Nov 111983: Dec 211984: Oct 301985: Oct 81986: Dec 111987: Oct 161988: Nov 301989: Oct 151990: Oct 71991: Oct 211992: Oct 141993: Nov 11994: Nov 131995: Nov 21996: Dec 181997: Dec 121998: Oct 301999: Oct 162000: Nov 72002: Oct 122003: Nov 12004: Nov 202005: Dec 62006: Oct 102008: Oct 122009: Oct 72010: Nov 202011: Oct 252012: Dec 152013: Nov 222014: Nov 172015: Nov 262016: Dec 72017: Oct 92018: Oct 152019: Oct 102020: Oct 232021: Nov 222022: Nov 152023: Oct 292024: Nov 292025: Dec 14

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
2025Apr 15Dec 14Feb 12none
2024Apr 22Nov 29nonenone
2023Apr 18Oct 29Feb 26Nov 26
2022Apr 15Nov 15Mar 11Nov 20
2021Apr 27Nov 22Apr 11Dec 27
2020Apr 17Oct 23Mar 13Oct 26
2019May 2Oct 10Feb 22Oct 28
2018Apr 3Oct 15Mar 6Oct 15
2017Apr 10Oct 9Apr 10none
2016Jan 11Dec 7Jan 3Dec 17
2015Apr 3Nov 26Feb 25Nov 28
2014Apr 13Nov 17Mar 23Dec 30
2013May 1Nov 22Jan 22Nov 22
2012Mar 19Dec 15Feb 5none
2011May 1Oct 25Feb 26Oct 27
2010May 6Nov 20Mar 18none
2009Apr 25Oct 7Mar 12Dec 7
2008Apr 23Oct 12Apr 3Oct 12
2007Mar 29no dataFeb 3no data
2006Mar 20Oct 10Feb 23Oct 31
2005Apr 13Dec 6Mar 15Dec 16
2004Apr 2Nov 20nonenone
2003Feb 28Nov 1Feb 26Nov 1
2002May 8Oct 12Mar 2Oct 12
2001Apr 5no dataFeb 15no data
2000Mar 31Nov 7Jan 30none
1999May 9Oct 16Mar 11Oct 16
1998Mar 30Oct 30Mar 7Dec 19
1997Apr 6Dec 12Apr 1none
1996Mar 28Dec 18Mar 25none
1995Mar 28Nov 2noneNov 2
1994Apr 4Nov 13Feb 5Dec 4
1993Feb 28Nov 1Feb 28Nov 14
1992Apr 22Oct 14Jan 20Oct 14
1991Mar 30Oct 21Jan 31Nov 29
1990Mar 15Oct 7Feb 19Dec 19
1989Mar 26Oct 15Mar 4none
1988Mar 31Nov 30Mar 16Dec 14
1987Mar 30Oct 16Mar 28Dec 13
1986Apr 24Dec 11Feb 10none
1985May 8Oct 8Mar 6Oct 8
1984May 6Oct 30Jan 19none
1983Apr 15Dec 21Feb 4Dec 21
1982May 13Nov 11Mar 26Nov 15
1981Apr 6no datanoneno data
1980Apr 3Nov 13Jan 31Dec 8
1979no dataNov 21no dataDec 11
1978Apr 7Nov 1Feb 11Nov 10
1977Apr 20Nov 8Feb 4Nov 19
1976Apr 9Oct 18Mar 12Nov 27
1975May 25Nov 18Mar 28Nov 19
1974Apr 25Oct 5Mar 8Dec 24
1973Apr 7Oct 3Jan 28none
1972Apr 30Sep 27Apr 20Dec 5
1971Apr 21Oct 17Mar 18Oct 28
1970Apr 17Sep 14Apr 3Dec 18
1969Apr 30Oct 13Mar 25Oct 13
1968May 7Oct 9Apr 18Dec 20
1967Apr 22Nov 20Mar 6Dec 12
1966Apr 29Oct 19Apr 19none
1965May 17Sep 17Mar 20Dec 15
1964May 2Oct 21Feb 28Nov 16
1963Apr 20Dec 2Mar 13Dec 11
1962Apr 11no dataFeb 27no data
1961Apr 27Oct 20Jan 22Nov 15
1960Apr 24Nov 4Mar 1Nov 5
1959May 4Oct 1Jan 4Nov 8
1958May 13Nov 15Mar 7Nov 16
1957Apr 15Nov 1Feb 6Nov 3
1956Apr 30Nov 14Mar 12Nov 20
1955Apr 15Nov 12Mar 21Nov 14
1954May 22Oct 24May 1Nov 30
1953Apr 12Dec 22Apr 9Dec 23
1952May 5Nov 3Apr 8Nov 22
1951Apr 21Nov 16Apr 21Dec 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.