Weather on December 17
San Mateo, CA
55 Years of Data
About This Date
December 17th in San Mateo, CA typically brings cool winter weather, with average highs around 58°F and lows near 43°F. Over 55 years of records, the warmest December 17th was in 2025 (57°F average), while the coldest was 1984 (42°F) — a 15°F range across recorded history. Rain or other precipitation has occurred on about 38% of December 17th dates historically, with the wettest December 17th recording 3.51" 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 17th in San Mateo, CA? Bring layers as temperatures can vary throughout the day. Consider bringing rain gear or an umbrella.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025warmest | 63° | 51° | 57° | 0.28" | — |
| 2024 | 56° | 49° | 52° | — | — |
| 2023 | 59° | 51° | 55° | 0.18" | — |
| 2022 | 56° | 40° | 48° | — | — |
| 2021 | 55° | 43° | 49° | — | — |
| 2020 | 58° | 48° | 53° | 1.12" | — |
| 2019 | 56° | 42° | 49° | 0.03" | — |
| 2018 | 60° | 50° | 55° | 0.05" | — |
| 2017 | 63° | 48° | 55° | — | — |
| 2016 | 52° | 38° | 45° | — | — |
| 2015 | 55° | 50° | 53° | — | — |
| 2014 | 60° | 50° | 55° | 0.53" | — |
| 2013 | 59° | 46° | 53° | — | — |
| 2012 | 59° | 50° | 55° | 0.38" | — |
| 2011 | 55° | 39° | 47° | — | — |
| 2010 | 57° | 48° | 53° | 1.75" | — |
| 2009 | 59° | 50° | 55° | — | — |
| 2008 | 51° | 34° | 42° | — | — |
| 2007 | 56° | 49° | 52° | 0.69" | — |
| 2006 | 52° | 39° | 45° | — | — |
| 2005 | 50° | 45° | 47° | 3.2" | — |
| 2004 | 59° | 44° | 52° | — | — |
| 2003 | 58° | 43° | 50° | — | — |
| 2002 | 55° | 45° | 50° | 0.84" | — |
| 2001 | 58° | 47° | 52° | 0.99" | — |
| 2000 | 63° | 44° | 53° | — | — |
| 1999 | 61° | 41° | 51° | — | — |
| 1998 | 60° | 47° | 53° | — | — |
| 1997 | 55° | 49° | 52° | 0.46" | — |
| 1996 | 63° | 44° | 53° | — | — |
| 1995 | 57° | 41° | 49° | — | — |
| 1994 | 52° | 41° | 46° | 0.03" | — |
| 1993 | 51° | 42° | 47° | — | — |
| 1992 | 53° | 42° | 48° | 0.66" | — |
| 1991 | 58° | 43° | 50° | 0.38" | — |
| 1990 | 59° | 40° | 49° | — | — |
| 1989 | 55° | 37° | 46° | — | — |
| 1988 | 56° | 44° | 50° | — | — |
| 1987 | 56° | 42° | 49° | — | — |
| 1986 | 58° | 41° | 49° | — | — |
| 1985 | 62° | 39° | 51° | — | — |
| 1984coldest | 51° | 34° | 42° | — | — |
| 1983 | 59° | 49° | 54° | 0.03" | — |
| 1982 | 59° | 44° | 52° | 0.23" | — |
| 1981 | 56° | 42° | 49° | — | — |
| 1980 | 62° | 42° | 52° | — | — |
| 1979 | 61° | 37° | 49° | — | — |
| 1978 | 63° | 34° | 48° | 0.58" | — |
| 1977 | 60° | 49° | 54° | 3.51" | — |
| 1976 | 64° | 35° | 50° | — | — |
| 1975 | 61° | 31° | 46° | — | — |
| 1974 | 62° | 44° | 53° | — | — |
| 1973 | 55° | 41° | 48° | — | — |
| 1972 | 55° | 42° | 49° | 1.73" | — |
| 1971 | 55° | 32° | 44° | — | — |