Frost history / Friday Harbor Ap, WA
Friday Harbor Ap, WA: frost dates by year
Last spring and first fall frost at NOAA station USW00094276, 1998 to 2024, measured from daily minimum temperatures.
Elevation 109 ft, 48.522, -123.023. Download the data (JSON), NOAA daily records
Summary at 32°F
| Last spring frost | First fall frost | |
|---|---|---|
| Median | Apr 9 | Nov 5 |
| Earliest | Feb 23 (2016) | Oct 9 (2019) |
| Latest | May 14 (1999) | Dec 4 (2016) |
| Trend | 14.9 days earlier per decade | 1.4 days later per decade |
| Years with data | 27 | 27, 1 with no freeze |
At 28°F (hard freeze) the median last spring date is Feb 25 and the median first fall date is Nov 28.
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 | Mar 5 | none | Jan 16 | none |
| 2023 | Apr 5 | Oct 28 | Feb 25 | none |
| 2022 | Mar 10 | Nov 7 | Mar 10 | Nov 28 |
| 2021 | Apr 12 | Nov 17 | Feb 13 | Dec 25 |
| 2020 | Apr 13 | Oct 25 | Jan 17 | Dec 24 |
| 2019 | Mar 10 | Oct 9 | Mar 5 | Nov 28 |
| 2018 | Mar 25 | Dec 3 | Feb 26 | Dec 5 |
| 2017 | Mar 6 | Nov 2 | Feb 8 | Nov 3 |
| 2016 | Feb 23 | Dec 4 | Jan 2 | Dec 7 |
| 2015 | Mar 4 | Nov 16 | Jan 1 | Nov 29 |
| 2014 | Mar 22 | Nov 12 | Feb 8 | Nov 12 |
| 2013 | May 1 | Nov 3 | Jan 13 | Nov 20 |
| 2012 | Apr 7 | Nov 10 | Feb 27 | none |
| 2011 | Apr 20 | Nov 6 | Feb 26 | Nov 19 |
| 2010 | Apr 9 | Nov 18 | none | Nov 21 |
| 2009 | Apr 15 | Oct 11 | Mar 12 | Dec 7 |
| 2008 | May 9 | Oct 15 | Apr 1 | Dec 13 |
| 2007 | Apr 20 | Oct 25 | Mar 1 | Dec 8 |
| 2006 | Mar 20 | Oct 30 | Feb 24 | Oct 30 |
| 2005 | Apr 9 | Nov 14 | Feb 21 | Dec 8 |
| 2004 | Apr 1 | Nov 4 | Feb 9 | none |
| 2003 | Mar 24 | Oct 31 | Feb 27 | Oct 31 |
| 2002 | May 7 | Oct 30 | Mar 20 | Oct 30 |
| 2001 | Apr 14 | Nov 17 | Mar 4 | Dec 4 |
| 2000 | Apr 24 | Nov 10 | Feb 19 | Nov 10 |
| 1999 | May 14 | Oct 26 | Mar 7 | none |
| 1998 | Apr 9 | Nov 11 | Mar 6 | Dec 19 |
"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.