Weather on December 20
Rancho Cucamonga, CA
55 Years of Data
About This Date
December 20th in Rancho Cucamonga, CA typically brings mild winter weather, with average highs around 67°F and lows near 42°F — a 25°F daily swing. Over 41 years of records, the warmest December 20th was in 1999 (66°F average), while the coldest was 1978 (45°F) — a 21°F range across recorded history. Rain or other precipitation has occurred on about 15% of December 20th dates historically, with the wettest December 20th recording 1.75" of rain. The last decade has been 2.9°F warmer on this date compared to 20-30 years ago.
The last decade has been 2.9°F warmer on this date compared to 20-30 years ago.
Planning for December 20th in Rancho Cucamonga, CA? Great weather for outdoor activities.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 67° | 45° | 56° | — | — |
| 2024 | 78° | 51° | 65° | — | — |
| 2023 | 68° | 55° | 62° | 0.91" | — |
| 2022 | 66° | 39° | 53° | — | — |
| 2021 | 69° | 37° | 53° | — | — |
| 2020 | 82° | 39° | 61° | — | — |
| 2019 | 76° | 42° | 59° | — | — |
| 2018 | 79° | 48° | 63° | — | — |
| 2017 | 62° | 43° | 52° | — | — |
| 2016 | 75° | 37° | 56° | — | — |
| 2015 | 59° | 44° | 52° | — | — |
| 2014 | 59° | 46° | 53° | — | — |
| 2013 | 61° | 39° | 50° | — | — |
| 2012 | 65° | 33° | 49° | — | — |
| 2011 | 64° | 40° | 52° | — | — |
| 2010 | 59° | 52° | 55° | 0.74" | — |
| 2009 | 70° | 46° | 58° | — | — |
| 2008 | 59° | 35° | 47° | — | — |
| 2007 | 58° | 48° | 53° | 0.94" | — |
| 2006 | 59° | 36° | 47° | — | — |
| 2005 | 77° | 47° | 62° | — | — |
| 2004 | 71° | 43° | 57° | — | — |
| 2003 | 64° | 47° | 55° | — | — |
| 2002 | 56° | 44° | 50° | 1.75" | — |
| 2001 | 56° | 42° | 49° | 0.36" | — |
| 2000 | 73° | 40° | 56° | — | — |
| 1999warmest | 80° | 51° | 66° | — | — |
| 1998 | 54° | 39° | 46° | 0.03" | — |
| 1983 | 58° | 47° | 52° | — | — |
| 1982 | 75° | 38° | 56° | — | — |
| 1981 | 65° | 40° | 52° | — | — |
| 1980 | 77° | 42° | 60° | — | — |
| 1979 | 64° | 39° | 52° | — | — |
| 1978coldest | 58° | 32° | 45° | — | — |
| 1977 | 67° | 41° | 54° | — | — |
| 1976 | 67° | 40° | 53° | — | — |
| 1975 | 69° | 37° | 53° | — | — |
| 1974 | 71° | 41° | 56° | — | — |
| 1973 | 68° | 37° | 53° | — | — |
| 1972 | 75° | 46° | 61° | — | — |
| 1971 | 60° | 34° | 47° | — | — |
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.