Frost history / Klamath Falls Intl Ap, OR
Klamath Falls Intl Ap, OR: frost dates by year
Last spring and first fall frost at NOAA station USW00094236, 1960 to 2024, measured from daily minimum temperatures.
Elevation 4,084 ft, 42.147, -121.724. Download the data (JSON), NOAA daily records
Summary at 32°F
| Last spring frost | First fall frost | |
|---|---|---|
| Median | Jun 9 | Sep 20 |
| Earliest | May 14 (1970) | Aug 25 (1960) |
| Latest | Jul 3 (1966) | Oct 11 (2022) |
| Trend | 0.9 days later per decade | little change (less than half a day per decade) |
| Years with data | 38 | 37 |
At 28°F (hard freeze) the median last spring date is May 18 and the median first fall date is Oct 4.
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)
First fall frost (32°F)
Dots are single years. The gray line is the median, the green line the fitted trend.
Year by year
| Year | Last spring 32°F | First fall 32°F | Last spring 28°F | First fall 28°F |
|---|---|---|---|---|
| 2024 | Jun 18 | Oct 6 | May 23 | Oct 17 |
| 2023 | Jun 21 | Sep 20 | Apr 25 | Sep 21 |
| 2022 | Jun 20 | Oct 11 | Jun 14 | Oct 22 |
| 2021 | Jun 7 | Sep 3 | May 26 | Oct 8 |
| 2020 | Jul 2 | Sep 20 | Jun 17 | Oct 22 |
| 2019 | Jun 21 | Sep 29 | Jun 8 | Oct 1 |
| 2018 | Jun 10 | Sep 11 | Jun 10 | Sep 24 |
| 2017 | Jun 14 | Sep 21 | May 18 | Sep 22 |
| 2016 | Jun 11 | Sep 5 | Apr 26 | Sep 23 |
| 2015 | May 16 | Sep 5 | May 13 | Oct 23 |
| 2014 | Jun 18 | Oct 1 | May 29 | Oct 12 |
| 2013 | Jun 21 | Sep 18 | May 22 | Sep 27 |
| 2012 | Jun 24 | Oct 4 | May 18 | Oct 8 |
| 2011 | Jun 8 | Oct 6 | May 24 | Oct 25 |
| 2010 | Jun 11 | Aug 31 | May 23 | Sep 10 |
| 2009 | May 15 | Sep 7 | May 8 | Sep 30 |
| 2008 | Jun 12 | Sep 1 | May 12 | Oct 10 |
| 2007 | Jun 7 | Sep 23 | May 13 | Sep 29 |
| 2006 | May 29 | Sep 20 | May 3 | Oct 17 |
| 2005 | Jun 7 | Sep 11 | Apr 25 | Sep 24 |
| 2004 | Jun 11 | Sep 20 | May 12 | Sep 21 |
| 2003 | May 20 | Sep 17 | May 18 | Sep 17 |
| 2002 | Jun 9 | Sep 8 | Jun 8 | Sep 30 |
| 2001 | Jun 18 | Sep 6 | Jun 13 | Sep 6 |
| 2000 | May 31 | Sep 23 | May 31 | Sep 23 |
| 1999 | Jun 9 | Aug 31 | Jun 8 | Oct 7 |
| 1998 | May 26 | Oct 3 | May 21 | Oct 4 |
| 1970 | May 14 | no data | May 12 | no data |
| 1969 | May 15 | Sep 14 | Apr 30 | Oct 4 |
| 1968 | Jun 8 | Sep 20 | May 7 | Sep 21 |
| 1967 | May 31 | Oct 3 | May 12 | Oct 6 |
| 1966 | Jul 3 | Sep 12 | Jun 4 | Oct 13 |
| 1965 | Jun 27 | Sep 17 | May 8 | Sep 19 |
| 1964 | May 22 | Sep 2 | May 8 | Oct 16 |
| 1963 | Jun 29 | Oct 7 | May 12 | Oct 7 |
| 1962 | Jun 5 | Oct 5 | Jun 4 | Oct 5 |
| 1961 | Jun 30 | Sep 21 | May 13 | Sep 23 |
| 1960 | May 24 | Aug 25 | May 22 | Oct 13 |
"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.