Weather on December 22
San Mateo, CA
55 Years of Data
Avg High
56°F
Avg Low
44°F
Warmest
2025
61°F avg
Coldest
1990
32°F avg
About This Date
December 22nd in San Mateo, CA typically brings cool winter weather, with average highs around 56°F and lows near 44°F. Over 55 years of records, the warmest December 22nd was in 2025 (61°F average), while the coldest was 1990 (32°F) — a 29°F range across recorded history. Rain or other precipitation has occurred on about 40% of December 22nd dates historically, with the wettest December 22nd recording 4.11" of rain. The last decade has been 1.5°F warmer on this date compared to 20-30 years ago.
The last decade has been 1.5°F warmer on this date compared to 20-30 years ago.
Planning for December 22nd in San Mateo, CA? Bring layers as temperatures can vary throughout the day. Consider bringing rain gear or an umbrella.
Warming Trend
1.2°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025warmest | 65° | 57° | 61° | 2.11" | — |
| 2024 | 59° | 54° | 56° | 0.46" | — |
| 2023 | 63° | 53° | 58° | — | — |
| 2022 | 56° | 47° | 51° | — | — |
| 2021 | 59° | 47° | 53° | 2.03" | — |
| 2020 | 60° | 48° | 54° | — | — |
| 2019 | 57° | 47° | 52° | 1.63" | — |
| 2018 | 56° | 44° | 50° | — | — |
| 2017 | 53° | 38° | 45° | — | — |
| 2016 | 58° | 42° | 50° | — | — |
| 2015 | 59° | 51° | 55° | 0.33" | — |
| 2014 | 65° | 54° | 59° | — | — |
| 2013 | 65° | 43° | 54° | — | — |
| 2012 | 59° | 50° | 55° | 1.45" | — |
| 2011 | 57° | 39° | 48° | — | — |
| 2010 | 55° | 49° | 52° | 0.41" | — |
| 2009 | 54° | 46° | 50° | — | — |
| 2008 | 53° | 43° | 48° | 0.61" | — |
| 2007 | 51° | 35° | 43° | — | — |
| 2006 | 55° | 45° | 50° | 0.03" | — |
| 2005 | 63° | 57° | 60° | 1.45" | — |
| 2004 | 58° | 47° | 52° | — | — |
| 2003 | 57° | 46° | 52° | — | — |
| 2002 | 57° | 40° | 48° | — | — |
| 2001 | 55° | 49° | 52° | 1.02" | — |
| 2000 | 58° | 49° | 53° | — | — |
| 1999 | 68° | 48° | 58° | — | — |
| 1998 | 46° | 31° | 38° | — | — |
| 1997 | 57° | 43° | 50° | — | — |
| 1996 | 57° | 46° | 52° | 0.18" | — |
| 1995 | 52° | 46° | 49° | 0.56" | — |
| 1994 | 52° | 39° | 45° | — | — |
| 1993 | 47° | 36° | 41° | — | — |
| 1992 | 54° | 39° | 46° | — | — |
| 1991 | 55° | 39° | 47° | — | — |
| 1990coldest | 38° | 27° | 32° | — | — |
| 1989 | 50° | 41° | 46° | — | — |
| 1988 | 57° | 43° | 50° | 2.41" | — |
| 1987 | 55° | 43° | 49° | 0.08" | — |
| 1986 | 54° | 44° | 49° | 0.41" | — |
| 1985 | 51° | 37° | 44° | — | — |
| 1984 | 55° | 35° | 45° | — | — |
| 1983 | 50° | 44° | 47° | 0.69" | — |
| 1982 | 60° | 48° | 54° | 4.11" | — |
| 1981 | 55° | 42° | 49° | — | — |
| 1980 | 59° | 47° | 53° | — | — |
| 1979 | 55° | 39° | 47° | — | — |
| 1978 | 57° | 32° | 45° | — | — |
| 1977 | 62° | 48° | 55° | 2.31" | — |
| 1976 | 57° | 37° | 47° | — | — |
| 1975 | 57° | 36° | 46° | 0.64" | — |
| 1974 | 55° | 42° | 49° | — | — |
| 1973 | 61° | 46° | 53° | 0.81" | — |
| 1972 | 58° | 51° | 54° | — | — |
| 1971 | 58° | 42° | 50° | 1.47" | — |
55 years of data from BURLINGAME