Weather on December 21
Mission Viejo, CA
55 Years of Data
Avg High
66°F
Avg Low
48°F
Warmest
2005
71°F avg
Coldest
1990
43°F avg
About This Date
December 21st in Mission Viejo, CA typically brings mild winter weather, with average highs around 66°F and lows near 48°F. Over 55 years of records, the warmest December 21st was in 2005 (71°F average), while the coldest was 1990 (43°F) — a 28°F range across recorded history. Rain or other precipitation has occurred on about 9% of December 21st dates historically, with the wettest December 21st recording 1.83" of rain. The last decade has been 5.6°F warmer on this date compared to 20-30 years ago.
The last decade has been 5.6°F warmer on this date compared to 20-30 years ago.
Planning for December 21st in Mission Viejo, CA? Great weather for outdoor activities.
Warming Trend
1.1°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 74° | 52° | 63° | — | — |
| 2024 | 71° | 51° | 61° | — | — |
| 2023 | 68° | 56° | 62° | — | — |
| 2022 | 73° | 50° | 62° | — | — |
| 2021 | 71° | 53° | 62° | — | — |
| 2020 | 82° | 56° | 69° | — | — |
| 2019 | 74° | 57° | 65° | — | — |
| 2018 | 68° | 53° | 61° | — | — |
| 2017 | 66° | 48° | 57° | — | — |
| 2016 | 68° | 57° | 63° | — | — |
| 2015 | 62° | 45° | 53° | — | — |
| 2014 | 68° | 51° | 60° | — | — |
| 2013 | 61° | 45° | 53° | — | — |
| 2012 | 64° | 46° | 55° | — | — |
| 2011 | 64° | 45° | 54° | — | — |
| 2010 | 59° | 52° | 55° | — | — |
| 2009 | 68° | 50° | 59° | — | — |
| 2008 | 67° | 46° | 56° | — | — |
| 2007 | 64° | 45° | 54° | — | — |
| 2006 | 64° | 41° | 53° | — | — |
| 2005warmest | 85° | 58° | 71° | — | — |
| 2004 | 67° | 48° | 57° | — | — |
| 2003 | 66° | 49° | 57° | — | — |
| 2002 | 65° | 46° | 55° | — | — |
| 2001 | 52° | 44° | 48° | — | — |
| 2000 | 72° | 47° | 59° | — | — |
| 1999 | 77° | 58° | 67° | — | — |
| 1998 | 56° | 46° | 51° | — | — |
| 1997 | 57° | 45° | 51° | 0.25" | — |
| 1996 | 59° | 46° | 53° | — | — |
| 1995 | 62° | 45° | 53° | — | — |
| 1994 | 73° | 49° | 61° | — | — |
| 1993 | 69° | 47° | 58° | — | — |
| 1992 | 61° | 41° | 51° | — | — |
| 1991 | 70° | 51° | 60° | — | — |
| 1990coldest | 48° | 37° | 43° | — | — |
| 1989 | 64° | 46° | 55° | — | — |
| 1988 | 60° | 40° | 50° | 1.83" | — |
| 1987 | 63° | 43° | 53° | — | — |
| 1986 | 69° | 43° | 56° | — | — |
| 1985 | 76° | 54° | 65° | — | — |
| 1984 | 59° | 39° | 49° | — | — |
| 1983 | 61° | 46° | 53° | — | — |
| 1982 | 60° | 47° | 53° | — | — |
| 1981 | 71° | 48° | 60° | 0.05" | — |
| 1980 | 71° | 49° | 60° | — | — |
| 1979 | 61° | 54° | 57° | 0.08" | — |
| 1978 | 62° | 43° | 52° | — | — |
| 1977 | 68° | 56° | 62° | 0.05" | — |
| 1976 | 72° | 46° | 59° | — | — |
| 1975 | 64° | 43° | 53° | — | — |
| 1974 | 66° | 44° | 55° | — | — |
| 1973 | 66° | 43° | 54° | — | — |
| 1972 | 76° | 56° | 66° | — | — |
| 1971 | 62° | 42° | 52° | — | — |
55 years of data from EL TORO MCAS