Weather on December 9
San Mateo, CA
55 Years of Data
Avg High
59°F
Avg Low
45°F
Warmest
1992
60°F avg
Coldest
1972
32°F avg
About This Date
December 9th in San Mateo, CA typically brings cool winter weather, with average highs around 59°F and lows near 45°F. Over 55 years of records, the warmest December 9th was in 1992 (60°F average), while the coldest was 1972 (32°F) — a 28°F range across recorded history. Rain or other precipitation has occurred on about 27% of December 9th dates historically, with the wettest December 9th recording 1.93" of rain. Temperatures on this date have remained relatively stable over the past several decades.
Temperatures on this date have remained relatively stable over the past several decades.
Planning for December 9th in San Mateo, CA? Bring layers as temperatures can vary throughout the day.
Warming Trend
0.8°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 54° | 45° | 49° | — | — |
| 2024 | 64° | 46° | 55° | — | — |
| 2023 | 61° | 43° | 52° | — | — |
| 2022 | 53° | 43° | 48° | — | — |
| 2021 | 57° | 46° | 52° | 0.03" | — |
| 2020 | 66° | 46° | 56° | — | — |
| 2019 | 56° | 49° | 52° | — | — |
| 2018 | 55° | 44° | 50° | — | — |
| 2017 | 63° | 43° | 53° | — | — |
| 2016 | 63° | 56° | 59° | 0.1" | — |
| 2015 | 65° | 54° | 59° | — | — |
| 2014 | 63° | 57° | 60° | — | — |
| 2013 | 52° | 36° | 44° | — | — |
| 2012 | 65° | 46° | 55° | — | — |
| 2011 | 58° | 39° | 48° | — | — |
| 2010 | 59° | 54° | 56° | — | — |
| 2009 | 46° | 36° | 41° | — | — |
| 2008 | 57° | 40° | 48° | — | — |
| 2007 | 58° | 40° | 49° | — | — |
| 2006 | 62° | 52° | 57° | 1.57" | — |
| 2005 | 63° | 45° | 54° | — | — |
| 2004 | 64° | 53° | 59° | 0.05" | — |
| 2003 | 56° | 46° | 51° | 1.93" | — |
| 2002 | 58° | 50° | 54° | 1.09" | — |
| 2001 | 56° | 49° | 52° | 0.18" | — |
| 2000 | 56° | 52° | 54° | — | — |
| 1999 | 57° | 47° | 52° | 0.74" | — |
| 1998 | 56° | 39° | 47° | — | — |
| 1997 | 56° | 40° | 48° | — | — |
| 1996 | 60° | 55° | 58° | 1.4" | — |
| 1995 | 59° | 50° | 55° | — | — |
| 1994 | 54° | 40° | 47° | — | — |
| 1993 | 63° | 53° | 58° | 0.38" | — |
| 1992warmest | 62° | 58° | 60° | 1.85" | — |
| 1991 | 66° | 44° | 55° | — | — |
| 1990 | 63° | 43° | 53° | — | — |
| 1989 | 63° | 47° | 55° | — | — |
| 1988 | 64° | 46° | 55° | — | — |
| 1987 | 63° | 55° | 59° | — | — |
| 1986 | 62° | 43° | 52° | — | — |
| 1985 | 57° | 39° | 48° | — | — |
| 1984 | 60° | 52° | 56° | 0.99" | — |
| 1983 | 60° | 53° | 57° | 1.52" | — |
| 1982 | 58° | 43° | 50° | — | — |
| 1981 | 61° | 48° | 54° | 0.38" | — |
| 1980 | 56° | 35° | 45° | — | — |
| 1979 | 57° | 44° | 51° | — | — |
| 1978 | 52° | 30° | 41° | — | — |
| 1977 | 62° | 37° | 50° | — | — |
| 1976 | 60° | 46° | 53° | — | — |
| 1975 | 62° | 39° | 51° | — | — |
| 1974 | 56° | 38° | 47° | — | — |
| 1973 | 58° | 45° | 51° | — | — |
| 1972coldest | 39° | 25° | 32° | — | — |
| 1971 | 52° | 36° | 44° | 0.36" | — |
55 years of data from BURLINGAME