Last Frost Day

Frost history / Mazama, WA

Mazama, WA: frost dates by year

Last spring and first fall frost at NOAA station USC00455133, 1969 to 2025, measured from daily minimum temperatures.

Elevation 2,141 ft, 48.601, -120.427. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 18Sep 23
EarliestApr 17 (2016)Aug 23 (1992)
LatestJul 8 (1981)Oct 17 (2022)
Trend5.7 days earlier per decade2.9 days later per decade
Years with data5453

At 28°F (hard freeze) the median last spring date is May 1 and the median first fall date is Oct 5.

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 31Apr 15Apr 30May 15May 30Jun 14Jun 29Jul 141970198019902000201020201969: May 181970: May 181972: May 261973: Jun 11974: May 311975: Jun 301976: Jun 51977: May 301978: Jun 151979: Jul 21980: May 31981: Jul 81982: May 41983: May 141984: May 251985: May 121986: Jun 191987: May 211988: May 51989: May 201990: May 211991: May 31992: May 221993: May 31994: Jun 71995: May 41996: May 211997: May 211998: May 161999: Jun 72000: May 132001: May 202002: May 152003: May 192004: May 62005: May 232006: May 142009: May 222010: May 262011: May 192012: Jun 82013: May 252014: May 122015: May 42016: Apr 172017: May 152018: Apr 242019: May 12020: May 82021: Apr 272022: May 132023: Apr 222024: May 32025: Apr 24

First fall frost (32°F)

Aug 13Aug 28Sep 12Sep 27Oct 12Oct 271970198019902000201020201969: Sep 151970: Sep 91972: Sep 201974: Sep 131975: Sep 191976: Sep 71977: Sep 171978: Oct 21979: Sep 291980: Sep 251981: Sep 231982: Sep 151983: Sep 201984: Sep 141985: Sep 221986: Sep 121987: Sep 281988: Sep 181989: Oct 31990: Oct 61991: Sep 221992: Aug 231993: Sep 131994: Oct 41995: Sep 211996: Sep 211997: Oct 61998: Oct 41999: Sep 282000: Sep 222001: Sep 292002: Sep 222003: Oct 92004: Sep 202005: Sep 232006: Oct 72009: Sep 292010: Oct 82011: Sep 302012: Oct 42013: Oct 12014: Sep 112015: Sep 232016: Sep 202017: Oct 42018: Sep 182019: Oct 12020: Sep 262021: Oct 22022: Oct 172023: Sep 292024: Oct 12025: Oct 6

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 24Oct 6Apr 23Oct 15
2024May 3Oct 1Apr 23Oct 3
2023Apr 22Sep 29Apr 20Oct 23
2022May 13Oct 17Apr 28Oct 29
2021Apr 27Oct 2Apr 20Oct 8
2020May 8Sep 26May 4Oct 22
2019May 1Oct 1May 1Oct 10
2018Apr 24Sep 18Apr 24Oct 5
2017May 15Oct 4May 15Oct 5
2016Apr 17Sep 20Mar 26Oct 11
2015May 4Sep 23Apr 26Oct 24
2014May 12Sep 11Apr 23Sep 11
2013May 25Oct 1May 1Oct 4
2012Jun 8Oct 4May 12Oct 4
2011May 19Sep 30Apr 28Oct 16
2010May 26Oct 8May 22Oct 16
2009May 22Sep 29May 2Oct 4
2006May 14Oct 7May 13Oct 9
2005May 23Sep 23Apr 13Oct 27
2004May 6Sep 20Apr 19Oct 23
2003May 19Oct 9May 19Oct 30
2002May 15Sep 22May 9Oct 12
2001May 20Sep 29May 6Oct 5
2000May 13Sep 22May 13Sep 23
1999Jun 7Sep 28May 11Sep 28
1998May 16Oct 4Apr 20Oct 4
1997May 21Oct 6May 2Oct 8
1996May 21Sep 21May 9Sep 23
1995May 4Sep 21Apr 20Oct 5
1994Jun 7Oct 4Apr 7Oct 4
1993May 3Sep 13Apr 20Oct 10
1992May 22Aug 23Apr 24Oct 14
1991May 3Sep 22Apr 17Oct 4
1990May 21Oct 6Apr 30Oct 6
1989May 20Oct 3May 12Oct 3
1988May 5Sep 18Apr 24Oct 17
1987May 21Sep 28May 2Oct 10
1986Jun 19Sep 12May 23Oct 11
1985May 12Sep 22May 12Sep 28
1984May 25Sep 14May 25Sep 27
1983May 14Sep 20Apr 29Sep 20
1982May 4Sep 15May 3Oct 1
1981Jul 8Sep 23Jul 8Sep 23
1980May 3Sep 25Apr 16Oct 9
1979Jul 2Sep 29Apr 24Oct 3
1978Jun 15Oct 2Apr 22Oct 13
1977May 30Sep 17May 12Oct 2
1976Jun 5Sep 7Jun 3Sep 8
1975Jun 30Sep 19Apr 30Oct 7
1974May 31Sep 13May 17Sep 27
1973Jun 1no dataMay 27no data
1972May 26Sep 20May 19Sep 20
1970May 18Sep 9May 11Sep 9
1969May 18Sep 15Apr 27Oct 4

"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.