Weather on December 18
Santa Rosa, CA
55 Years of Data
Avg High
58°F
Avg Low
38°F
Warmest
1997
55°F avg
Coldest
1984
40°F avg
About This Date
December 18th in Santa Rosa, CA typically brings cool winter weather, with average highs around 58°F and lows near 38°F. Over 55 years of records, the warmest December 18th was in 1997 (55°F average), while the coldest was 1984 (40°F) — a 15°F range across recorded history. Rain or other precipitation has occurred on about 33% of December 18th dates historically, with the wettest December 18th recording 5.72" of rain. The last decade has been 2.9°F cooler on this date compared to 20-30 years ago.
The last decade has been 2.9°F cooler on this date compared to 20-30 years ago.
Planning for December 18th in Santa Rosa, CA? Bring layers as temperatures can vary throughout the day. Consider bringing rain gear or an umbrella.
Warming Trend
0.4°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 59° | 47° | 53° | 0.08" | — |
| 2024 | 60° | 38° | 49° | — | — |
| 2023 | 60° | 50° | 55° | 2.9" | — |
| 2022 | 55° | 27° | 41° | — | — |
| 2021 | 51° | 31° | 41° | — | — |
| 2020 | 60° | 33° | 47° | — | — |
| 2019 | 57° | 36° | 46° | 1.12" | — |
| 2018 | 56° | 43° | 49° | 0.15" | — |
| 2017 | 61° | 34° | 47° | — | — |
| 2016 | 53° | 33° | 43° | — | — |
| 2015 | 53° | 47° | 50° | — | — |
| 2014 | 55° | 48° | 52° | — | — |
| 2013 | 57° | 44° | 51° | — | — |
| 2012 | 49° | 37° | 43° | — | — |
| 2011 | 58° | 33° | 45° | — | — |
| 2010 | 57° | 46° | 52° | 1.57" | — |
| 2009 | 66° | 43° | 54° | 0.05" | — |
| 2008 | 53° | 28° | 41° | 0.15" | — |
| 2007 | 58° | 47° | 52° | 3.23" | — |
| 2006 | 59° | 27° | 43° | — | — |
| 2005 | 59° | 44° | 52° | 5.72" | — |
| 2004 | 65° | 35° | 50° | — | — |
| 2003 | 63° | 32° | 47° | — | — |
| 2002 | 55° | 34° | 44° | 0.05" | — |
| 2001 | 53° | 38° | 45° | 0.03" | — |
| 2000 | 64° | 34° | 49° | — | — |
| 1999 | 64° | 40° | 52° | — | — |
| 1998 | 65° | 39° | 52° | — | — |
| 1997warmest | 63° | 47° | 55° | — | — |
| 1996 | 69° | 39° | 54° | — | — |
| 1995 | 56° | 44° | 50° | 0.74" | — |
| 1994 | 50° | 43° | 46° | 0.2" | — |
| 1993 | 55° | 32° | 44° | — | — |
| 1992 | 53° | 31° | 42° | 0.05" | — |
| 1991 | 58° | 47° | 52° | 1.14" | — |
| 1990 | 60° | 34° | 47° | — | — |
| 1989 | 56° | 38° | 47° | — | — |
| 1988 | 55° | 36° | 45° | — | — |
| 1987 | 61° | 31° | 46° | — | — |
| 1986 | 56° | 43° | 49° | 1.02" | — |
| 1985 | 56° | 28° | 42° | — | — |
| 1984coldest | 47° | 34° | 40° | — | — |
| 1983 | 54° | 47° | 50° | — | — |
| 1982 | 60° | 35° | 48° | — | — |
| 1981 | 60° | 47° | 53° | 0.23" | — |
| 1980 | 56° | 39° | 47° | — | — |
| 1979 | 60° | 31° | 45° | — | — |
| 1978 | 53° | 36° | 44° | — | — |
| 1977 | 58° | 37° | 47° | — | — |
| 1976 | 67° | 29° | 48° | — | — |
| 1975 | 63° | 29° | 46° | — | — |
| 1974 | 58° | 32° | 45° | — | — |
| 1973 | 63° | 34° | 48° | — | — |
| 1972 | 52° | 44° | 48° | 0.99" | — |
| 1971 | 56° | 28° | 42° | — | — |
55 years of data from SANTA ROSA