Weather on December 21
Fullerton, CA
55 Years of Data
Avg High
68°F
Avg Low
46°F
Warmest
2005
69°F avg
Coldest
1988
42°F avg
About This Date
December 21st in Fullerton, CA typically brings mild winter weather, with average highs around 68°F and lows near 46°F. Over 55 years of records, the warmest December 21st was in 2005 (69°F average), while the coldest was 1988 (42°F) — a 27°F range across recorded history. Rain or other precipitation has occurred on about 20% of December 21st dates historically, with the wettest December 21st recording 4.52" of rain. The last decade has been 5.0°F warmer on this date compared to 20-30 years ago.
The last decade has been 5.0°F warmer on this date compared to 20-30 years ago.
Planning for December 21st in Fullerton, CA? Great weather for outdoor activities.
Warming Trend
0.9°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 70° | 50° | 60° | — | — |
| 2024 | 68° | 45° | 56° | — | — |
| 2023 | 70° | 59° | 64° | 1.22" | — |
| 2022 | 77° | 45° | 61° | — | — |
| 2021 | 71° | 54° | 62° | — | — |
| 2020 | 84° | 53° | 69° | — | — |
| 2019 | 78° | 53° | 66° | — | — |
| 2018 | 73° | 53° | 63° | — | — |
| 2017 | 65° | 43° | 54° | — | — |
| 2016 | 77° | 58° | 67° | 0.94" | — |
| 2015 | 64° | 43° | 53° | — | — |
| 2014 | 70° | 50° | 60° | — | — |
| 2013 | 61° | 45° | 53° | — | — |
| 2012 | 69° | 41° | 55° | — | — |
| 2011 | 64° | 41° | 53° | — | — |
| 2010 | 60° | 53° | 57° | 4.52" | — |
| 2009 | 65° | 44° | 54° | — | — |
| 2008 | 68° | 43° | 55° | — | — |
| 2007 | 67° | 43° | 55° | — | — |
| 2006 | 65° | 40° | 52° | — | — |
| 2005warmest | 83° | 55° | 69° | — | — |
| 2004 | 69° | 53° | 61° | — | — |
| 2003 | 66° | 54° | 60° | 0.03" | — |
| 2002 | 59° | 46° | 53° | 0.13" | — |
| 2001 | 58° | 46° | 52° | 1.4" | — |
| 2000 | 73° | 41° | 57° | — | — |
| 1999 | 79° | 46° | 62° | — | — |
| 1998 | 57° | 38° | 47° | — | — |
| 1997 | 65° | 44° | 54° | 0.15" | — |
| 1996 | 70° | 44° | 57° | — | — |
| 1995 | 63° | 46° | 54° | — | — |
| 1994 | 78° | 44° | 61° | — | — |
| 1993 | 69° | 52° | 60° | — | — |
| 1992 | 63° | 41° | 52° | — | — |
| 1991 | 72° | 54° | 63° | — | — |
| 1990 | 50° | 33° | 42° | — | — |
| 1989 | 67° | 44° | 55° | — | — |
| 1988coldest | 60° | 24° | 42° | 2.24" | — |
| 1987 | 69° | 42° | 56° | — | — |
| 1986 | 75° | 45° | 60° | — | — |
| 1985 | 77° | 46° | 62° | — | — |
| 1984 | 62° | 40° | 51° | — | — |
| 1983 | 62° | 45° | 53° | — | — |
| 1982 | 63° | 48° | 55° | — | — |
| 1981 | 70° | 49° | 59° | 0.1" | — |
| 1980 | 77° | 45° | 61° | — | — |
| 1979 | 63° | 48° | 55° | 0.33" | — |
| 1978 | 68° | 38° | 53° | — | — |
| 1977 | 69° | 52° | 60° | 0.13" | — |
| 1976 | 75° | 42° | 59° | — | — |
| 1975 | 67° | 42° | 54° | — | — |
| 1974 | 72° | 44° | 58° | — | — |
| 1973 | 67° | 42° | 54° | — | — |
| 1972 | 82° | 49° | 65° | — | — |
| 1971 | 62° | 37° | 50° | — | — |
55 years of data from ANAHEIM