As of 05:19 PDT

Rancho Cucamonga, CA weather in December

81°

Rancho Cucamonga, Sunday, 9 August, 05:19

Mostly clear. Feels like 80°. High 100°, low 73°.

Pressure29.88 inHg

Wind3.1 mph W

Humidity25%

Visibility6.2 mi

Dew point46°

See detailed hourly forecast

In December, Rancho Cucamonga, CA averages a high of 61.7° and a low of 42.3°. About 2.9 inches of precipitation fall over the month (6 wet days). The record high is 82.4° (2021) and the record low 25.9° (1990). Normals are computed over the last 60 years.

Day	High	Low	Chance of precip.	Record high	Record low
1	64.8°	44.1°	13%	82.4° (2021)	31.1° (2004)
2	64.6°	43.7°	13%	78.4° (1977)	32.7° (2004)
3	64.9°	44.4°	17%	76.8° (1979)	34° (2004)
4	64.4°	43.7°	20%	81.5° (1979)	32° (2004)
5	64.4°	44.1°	20%	80.4° (1977)	32.7° (1972)
6	64.4°	44.8°	18%	80.6° (1979)	30.7° (1978)
7	63.1°	44.8°	27%	77.5° (1979)	27.9° (1978)
8	63.3°	43.5°	22%	81° (2015)	27.1° (1978)
9	63.5°	43°	15%	80.1° (2025)	27° (1972)
10	63.3°	43.2°	10%	82.2° (2025)	32° (1985)
11	62.2°	43.5°	22%	81° (2025)	29.7° (1972)
12	61.5°	42.6°	13%	80.1° (2017)	26.6° (1972)
13	61.5°	41.9°	17%	79.3° (2017)	29.5° (1985)
14	61.5°	41.4°	17%	75.6° (2017)	27.9° (1967)
15	61.5°	41.2°	12%	76.3° (2017)	30° (1987)
16	62.2°	42.1°	23%	79.7° (2013)	31.8° (2015)
17	61.7°	42.4°	25%	80.2° (2013)	31.5° (1965)
18	60.8°	42.1°	22%	79.3° (2024)	30.4° (1965)
19	60.4°	41.7°	22%	77.2° (2024)	30° (2012)
20	60.6°	41.5°	22%	76.5° (2020)	27.7° (1967)
21	60.4°	41.4°	22%	78.8° (2005)	26.4° (1968)
22	59.7°	42.1°	20%	73.4° (2025)	27.9° (1998)
23	60.6°	41.5°	22%	76.8° (2005)	25.9° (1990)
24	61°	41.4°	17%	78.3° (2005)	28.8° (1990)
25	60.8°	41.2°	23%	77.4° (2022)	27.7° (1990)
26	60.1°	40.8°	22%	79.3° (1980)	27.9° (1987)
27	59.5°	40.3°	15%	78.1° (2013)	29.3° (1988)
28	58.6°	40.8°	25%	80.8° (2017)	28.8° (1987)
29	59.2°	41.4°	28%	80.6° (2017)	27.9° (1971)
30	59.5°	40.6°	22%	77.7° (1980)	28.6° (1982)
31	59.4°	40.8°	20%	77.7° (2011)	30.2° (1987)