Weather on December 20
San Marcos, CA
55 Years of Data
Avg High
69°F
Avg Low
42°F
Warmest
1991
68°F avg
Coldest
1992
44°F avg
About This Date
December 20th in San Marcos, CA typically brings mild winter weather, with average highs around 69°F and lows near 42°F — a 27°F daily swing. Over 55 years of records, the warmest December 20th was in 1991 (68°F average), while the coldest was 1992 (44°F) — a 24°F range across recorded history. Rain or other precipitation has occurred on about 18% of December 20th dates historically, with the wettest December 20th recording 3.15" 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 20th in San Marcos, CA? Great weather for outdoor activities.
Warming Trend
0.9°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 70° | 49° | 59° | — | — |
| 2024 | 79° | 45° | 62° | — | — |
| 2023 | 74° | 55° | 64° | — | — |
| 2022 | 69° | 39° | 54° | — | — |
| 2021 | 70° | 37° | 53° | — | — |
| 2020 | 82° | 41° | 62° | — | — |
| 2019 | 77° | 42° | 60° | — | — |
| 2018 | 78° | 44° | 61° | — | — |
| 2017 | 65° | 40° | 52° | — | — |
| 2016 | 78° | 42° | 60° | — | — |
| 2015 | 61° | 47° | 54° | 0.33" | — |
| 2014 | 65° | 46° | 55° | — | — |
| 2013 | 62° | 39° | 51° | — | — |
| 2012 | 71° | 34° | 52° | — | — |
| 2011 | 64° | 46° | 55° | — | — |
| 2010 | 61° | 57° | 59° | 3.15" | — |
| 2009 | 71° | 51° | 61° | — | — |
| 2008 | 58° | 40° | 49° | — | — |
| 2007 | 60° | 53° | 57° | 0.1" | — |
| 2006 | 61° | 32° | 46° | — | — |
| 2005 | 81° | 45° | 63° | — | — |
| 2004 | 77° | 41° | 59° | — | — |
| 2003 | 68° | 45° | 56° | — | — |
| 2002 | 56° | 43° | 49° | 2.21" | — |
| 2001 | 76° | 36° | 56° | — | — |
| 2000 | 75° | 40° | 57° | — | — |
| 1999 | 81° | 42° | 61° | — | — |
| 1998 | 81° | 44° | 62° | 0.76" | — |
| 1997 | 79° | 58° | 68° | — | — |
| 1996 | 73° | 36° | 54° | — | — |
| 1995 | 63° | 44° | 53° | — | — |
| 1994 | 78° | 39° | 59° | — | — |
| 1993 | 67° | 41° | 54° | — | — |
| 1992coldest | 59° | 29° | 44° | — | — |
| 1991warmest | 70° | 67° | 68° | — | — |
| 1990 | 53° | 44° | 49° | 0.71" | — |
| 1989 | 69° | 39° | 54° | — | — |
| 1988 | 65° | 43° | 54° | — | — |
| 1987 | 67° | 38° | 52° | 1.73" | — |
| 1986 | 65° | 42° | 53° | 0.38" | — |
| 1985 | 78° | 41° | 60° | — | — |
| 1984 | 60° | 31° | 45° | 1.93" | — |
| 1983 | 68° | 47° | 57° | — | — |
| 1982 | 76° | 38° | 57° | — | — |
| 1981 | 69° | 42° | 56° | — | — |
| 1980 | 75° | 40° | 57° | — | — |
| 1979 | 68° | 38° | 53° | — | — |
| 1978 | 60° | 31° | 45° | — | — |
| 1977 | 67° | 49° | 58° | — | — |
| 1976 | 70° | 41° | 55° | — | — |
| 1975 | 58° | 34° | 46° | 0.25" | — |
| 1974 | 75° | 37° | 56° | — | — |
| 1973 | 76° | 37° | 56° | — | — |
| 1972 | 78° | 42° | 60° | — | — |
| 1971 | 62° | 33° | 48° | — | — |
55 years of data from ESCONDIDO #2