Weather on December 31
San Marcos, CA
55 Years of Data
About This Date
December 31st in San Marcos, CA typically brings mild winter weather, with average highs around 66°F and lows near 43°F. Over 55 years of records, the warmest December 31st was in 1997 (65°F average), while the coldest was 2010 (44°F) — a 21°F range across recorded history. Rain or other precipitation has occurred on about 29% of December 31st dates historically, with the wettest December 31st recording 2.62" of rain. The last decade has been 1.0°F warmer on this date compared to 20-30 years ago.
The last decade has been 1.0°F warmer on this date compared to 20-30 years ago.
Planning for December 31st in San Marcos, CA? Great weather for outdoor activities.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 73° | 58° | 65° | 0.71" | — |
| 2024 | 64° | 45° | 54° | 0.03" | — |
| 2023 | 62° | 50° | 56° | 0.03" | — |
| 2022 | 62° | 54° | 58° | 0.05" | — |
| 2021 | 63° | 50° | 56° | 0.08" | — |
| 2020 | 64° | 43° | 53° | — | — |
| 2019 | 70° | 49° | 59° | — | — |
| 2018 | 59° | 52° | 55° | 0.2" | — |
| 2017 | 71° | 45° | 58° | — | — |
| 2016 | 56° | 53° | 54° | 0.74" | — |
| 2015 | 66° | 36° | 51° | — | — |
| 2014 | 50° | 38° | 44° | 1.68" | — |
| 2013 | 73° | 38° | 55° | — | — |
| 2012 | 59° | 33° | 46° | — | — |
| 2011 | 77° | 44° | 61° | — | — |
| 2010coldest | 56° | 33° | 44° | — | — |
| 2009 | 70° | 48° | 59° | 0.03" | — |
| 2008 | 61° | 42° | 51° | 0.03" | — |
| 2007 | 66° | 43° | 54° | — | — |
| 2006 | 71° | 34° | 52° | — | — |
| 2005 | 61° | 48° | 54° | 0.64" | — |
| 2004 | 58° | 44° | 51° | 0.81" | — |
| 2003 | 66° | 33° | 50° | — | — |
| 2002 | 62° | 42° | 52° | — | — |
| 2001 | 61° | 55° | 58° | 0.13" | — |
| 2000 | 77° | 38° | 57° | — | — |
| 1999 | 62° | 47° | 54° | — | — |
| 1998 | 74° | 41° | 57° | — | — |
| 1997warmest | 79° | 52° | 65° | — | — |
| 1996 | 66° | 54° | 60° | — | — |
| 1995 | 70° | 46° | 58° | — | — |
| 1994 | 64° | 40° | 52° | — | — |
| 1993 | 73° | 40° | 56° | — | — |
| 1992 | 62° | 37° | 50° | — | — |
| 1991 | 67° | 44° | 55° | — | — |
| 1990 | 73° | 33° | 53° | — | — |
| 1989 | 77° | 38° | 57° | — | — |
| 1988 | 57° | 34° | 45° | — | — |
| 1987 | 65° | 35° | 50° | — | — |
| 1986 | 69° | 40° | 54° | — | — |
| 1985 | 68° | 48° | 58° | — | — |
| 1984 | 64° | 38° | 51° | — | — |
| 1983 | 73° | 47° | 60° | — | — |
| 1982 | 61° | 29° | 45° | — | — |
| 1981 | 58° | 51° | 54° | 0.23" | — |
| 1980 | 81° | 45° | 63° | — | — |
| 1979 | 71° | 47° | 59° | — | — |
| 1978 | 64° | 34° | 49° | — | — |
| 1977 | 61° | 50° | 55° | 0.05" | — |
| 1976 | 58° | 52° | 55° | 2.62" | — |
| 1975 | 59° | 46° | 53° | — | — |
| 1974 | 61° | 38° | 49° | — | — |
| 1973 | 64° | 39° | 52° | — | — |
| 1972 | 67° | 28° | 47° | — | — |
| 1971 | 65° | 36° | 50° | — | — |
San Marcos, CA Temperature Range by Month
Average monthly highs and lows. The shaded band shows the typical daily temperature range.
San Marcos, CA Monthly Precipitation
Average rainfall per month, in inches.
San Marcos, CA Daily Temperature Calendar
Average daily high temperature for every day of the year. Each cell is the climatological mean for that calendar day across 55 years of NOAA data.
Best Time to Visit San Marcos, CA
Most pleasant months in San Marcos, CA: June.