Frost history / Concord Buchanan Fld, CA
Concord Buchanan Fld, CA: frost dates by year
Last spring and first fall frost at NOAA station USW00023254, 1999 to 2024, measured from daily minimum temperatures.
Elevation 18 ft, 37.992, -122.055. Download the data (JSON), NOAA daily records
Summary at 32°F
| Last spring frost | First fall frost | |
|---|---|---|
| Median | Feb 3 | Dec 6 |
| Earliest | Jan 1 (2016) | Nov 23 (2003) |
| Latest | Feb 27 (2011) | Dec 30 (2014) |
| Trend | 2.4 days earlier per decade | 3.3 days earlier per decade |
| Years with data | 25, 5 with no freeze | 26, 7 with no freeze |
At 28°F (hard freeze) the median last spring date is Jan 16 and the median first fall date is Dec 18.
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 | Jan 7 | none | none | none |
| 2023 | Feb 15 | Nov 27 | none | none |
| 2022 | Feb 24 | Dec 2 | none | none |
| 2021 | none | none | none | none |
| 2020 | none | none | none | none |
| 2019 | Feb 19 | none | none | none |
| 2018 | Feb 23 | none | none | none |
| 2017 | Jan 6 | none | none | none |
| 2016 | Jan 1 | Dec 17 | none | none |
| 2015 | Jan 3 | Nov 29 | none | none |
| 2014 | Jan 21 | Dec 30 | none | none |
| 2013 | Feb 20 | Dec 4 | Jan 19 | Dec 5 |
| 2012 | Jan 18 | Dec 19 | Jan 16 | Dec 20 |
| 2011 | Feb 27 | Dec 6 | none | Dec 24 |
| 2010 | none | Nov 24 | none | none |
| 2009 | Jan 27 | Dec 7 | Jan 4 | Dec 9 |
| 2008 | Feb 5 | Dec 17 | none | none |
| 2007 | Jan 25 | Dec 13 | Jan 16 | none |
| 2006 | Feb 20 | Nov 29 | none | Dec 18 |
| 2005 | none | Dec 4 | none | none |
| 2004 | Jan 23 | Nov 29 | none | none |
| 2003 | Feb 9 | Nov 23 | none | none |
| 2002 | Jan 31 | none | none | none |
| 2001 | Feb 13 | Dec 15 | none | none |
| 2000 | none | Dec 29 | none | none |
| 1999 | no data | Dec 15 | no data | none |
"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.