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Weather on December 15

Rancho Cucamonga, CA

55 Years of Data

Avg High
67°F
Avg Low
42°F
Warmest
1980
68°F avg
Coldest
1971
43°F avg

About This Date

December 15th 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 15th was in 1980 (68°F average), while the coldest was 1971 (43°F) — a 25°F range across recorded history. Rain or other precipitation has occurred on about 10% of December 15th dates historically, with the wettest December 15th recording 4.32" of rain. The last decade has been 1.6°F warmer on this date compared to 20-30 years ago.

The last decade has been 1.6°F warmer on this date compared to 20-30 years ago.

Planning for December 15th in Rancho Cucamonga, CA? Great weather for outdoor activities.

YearHighLowAvgPrecipSnow
202578°49°63°
202466°45°55°
202379°44°61°
202260°40°50°
202153°36°44°
202069°42°56°
201962°46°54°
201874°46°60°
201781°48°64°
201667°51°59°0.76"
201558°32°45°
201464°46°55°
201381°42°61°
201257°43°50°0.08"
201155°39°47°1.12"
201055°50°53°
200969°41°55°
200851°43°47°4.32"
200768°37°53°
200671°47°59°
200564°43°53°
200477°45°61°
200368°41°55°
200264°50°57°
200157°33°45°
200060°44°52°
199972°43°57°
199879°41°60°
198368°40°54°
198269°35°52°
198174°42°58°
1980warmest83°53°68°
197974°42°58°
197868°42°55°
197765°46°55°
197677°46°62°
197566°31°48°
197470°40°55°
197372°39°55°
197262°31°46°
1971coldest54°33°43°
41 years of data from ONTARIO INTL AP

Rancho Cucamonga, CA Temperature Range by Month

Average monthly highs and lows. The shaded band shows the typical daily temperature range.

30°50°70°90°JFMAMJJASOND
Avg high Avg low

Rancho Cucamonga, CA Monthly Precipitation

Average rainfall per month, in inches.

0"7.4"14.7"JFMAMJJASOND
Rain (in)

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.

151015202531JanFebMarAprMayJunJulAugSepOctNovDec
Cooler
Hotter
20°40°60°80°100°

Best Time to Visit Rancho Cucamonga, CA

Rancho Cucamonga, CA has no months that meet our "pleasant" threshold — every season has tradeoffs.

Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Pleasant (65-82°F, ≤2.5" rain) Mild Less ideal

Browse Weather History

Weather data provided by NOAA Climate Data Online. Not for critical planning.

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