Weather on December 21
Rancho Cucamonga, CA
55 Years of Data
About This Date
December 21st in Rancho Cucamonga, CA typically brings mild winter weather, with average highs around 65°F and lows near 44°F. Over 41 years of records, the warmest December 21st was in 2005 (66°F average), while the coldest was 1998 (43°F) — a 23°F range across recorded history. Rain or other precipitation has occurred on about 22% of December 21st dates historically, with the wettest December 21st recording 7.21" of rain. The last decade has been 4.0°F warmer on this date compared to 20-30 years ago.
The last decade has been 4.0°F warmer on this date compared to 20-30 years ago.
Planning for December 21st in Rancho Cucamonga, CA? Great weather for outdoor activities.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 75° | 47° | 61° | — | — |
| 2024 | 72° | 45° | 58° | — | — |
| 2023 | 68° | 55° | 62° | — | — |
| 2022 | 72° | 40° | 56° | — | — |
| 2021 | 67° | 47° | 57° | — | — |
| 2020 | 82° | 46° | 64° | — | — |
| 2019 | 73° | 47° | 60° | — | — |
| 2018 | 71° | 51° | 61° | — | — |
| 2017 | 60° | 44° | 52° | — | — |
| 2016 | 62° | 49° | 55° | 0.66" | — |
| 2015 | 59° | 41° | 50° | 0.05" | — |
| 2014 | 65° | 44° | 54° | — | — |
| 2013 | 59° | 40° | 49° | — | — |
| 2012 | 65° | 33° | 49° | — | — |
| 2011 | 62° | 39° | 51° | — | — |
| 2010 | 55° | 50° | 53° | 7.21" | — |
| 2009 | 63° | 48° | 55° | — | — |
| 2008 | 64° | 37° | 51° | — | — |
| 2007 | 58° | 44° | 51° | 0.08" | — |
| 2006 | 62° | 36° | 49° | — | — |
| 2005warmest | 82° | 50° | 66° | — | — |
| 2004 | 65° | 48° | 56° | — | — |
| 2003 | 64° | 47° | 55° | — | — |
| 2002 | 55° | 46° | 51° | 0.08" | — |
| 2001 | 52° | 44° | 48° | 0.61" | — |
| 2000 | 74° | 42° | 58° | — | — |
| 1999 | 74° | 47° | 60° | — | — |
| 1998coldest | 52° | 34° | 43° | — | — |
| 1983 | 57° | 47° | 52° | — | — |
| 1982 | 66° | 36° | 51° | — | — |
| 1981 | 65° | 50° | 57° | 0.1" | — |
| 1980 | 78° | 42° | 60° | — | — |
| 1979 | 57° | 48° | 53° | 0.38" | — |
| 1978 | 63° | 34° | 48° | — | — |
| 1977 | 63° | 48° | 55° | 0.05" | — |
| 1976 | 68° | 40° | 54° | — | — |
| 1975 | 63° | 39° | 51° | — | — |
| 1974 | 70° | 43° | 56° | — | — |
| 1973 | 63° | 41° | 52° | — | — |
| 1972 | 76° | 47° | 61° | — | — |
| 1971 | 61° | 37° | 49° | — | — |
Rancho Cucamonga, CA Temperature Range by Month
Average monthly highs and lows. The shaded band shows the typical daily temperature range.
Rancho Cucamonga, CA Monthly Precipitation
Average rainfall per month, in inches.
Rancho Cucamonga, 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 Rancho Cucamonga, CA
Rancho Cucamonga, CA has no months that meet our "pleasant" threshold — every season has tradeoffs.