What is the highest temperature ever recorded in Rancho Cucamonga, CA?

The record high temperature in Rancho Cucamonga, CA is 121°F, recorded on September 6, 2020.

What is the lowest temperature ever recorded in Rancho Cucamonga, CA?

The record low temperature in Rancho Cucamonga, CA is 19°F, recorded on March 12, 1986.

Historical Weather in Rancho Cucamonga, CA

Name: Rancho Cucamonga, CA Temperature Records
Creator: NOAA

See 55+ years of weather history for any date in Rancho Cucamonga going back to 1970.

Part of California weather history · California temperature records

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Today in Rancho Cucamonga Weather HistorySee records, averages, and 55+ years of data for today's date

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Monthly Climate Averages

Historical temperature and precipitation averages for Rancho Cucamonga, CA, based on 55+ years of weather data.

Warmest MonthAugustAvg High: 93°F / Low: 63°F

Coldest MonthJanuaryAvg High: 66°F / Low: 43°F

Jan

66°/ 43°

💧 12.9"

Feb

68°/ 44°

💧 14.7"

Mar

70°/ 47°

💧 10.7"

Apr

74°/ 49°

💧 5.6"

May

79°/ 53°

💧 4.6"

Jun

87°/ 58°

💧 1.5"

Jul

93°/ 63°

💧 2.4"

Aug

93°/ 63°

💧 8.4"

Sep

90°/ 62°

💧 6.3"

Oct

81°/ 55°

💧 5.8"

Nov

73°/ 47°

💧 8.1"

Dec

67°/ 43°

💧 10.9"

Temperatures in Fahrenheit. Precipitation and snowfall in inches.

Rancho Cucamonga, CA Temperature Range by Month

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

Avg high Avg low

Rancho Cucamonga, CA Monthly Precipitation

Average rainfall per month, in inches.

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.

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Best Time to Visit Rancho Cucamonga, CA

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

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Feb

Mar

Apr

May

Jun

Jul

Aug

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Oct

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Dec

Pleasant (65-82°F, ≤2.5" rain) Mild Less ideal

Rancho Cucamonga Temperature Records

Record High: The hottest temperature ever recorded in Rancho Cucamonga, CA is 121°F, set on September 6, 2020.
Record Low: The coldest temperature ever recorded in Rancho Cucamonga, CA is 19°F, set on March 12, 1986.
Data Coverage: Based on 29 years of data from NOAA weather station: ONTARIO INTL AP.

All-Time Record High

121°F

September 6, 2020

All-Time Record Low

19°F

March 12, 1986

Monthly Temperature Records in Rancho Cucamonga

Month	Record High	Record Low
January	93°F(2021)	20°F(2007)
February	95°F(2016)	23°F(1990)
March	97°F(2007)	19°F(1986)
April	106°F(2004)	28°F(1999)
May	106°F(2003)	32°F(1988)
June	115°F(2016)	36°F(1988)
July	120°F(2018)	42°F(2010)
August	115°F(2017)	45°F(2010)
September	121°F(2020)	41°F(2007)
October	111°F(2020)	33°F(2009)
November	100°F(2010)	27°F(2000)
December	92°F(2021)	20°F(1987)