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21°
Partly Cloudy
Feels Like: 20°
Min: 17°
Max: 29°
The next few hours will be overcast, with today reaching 29°C and dropping to 16°C. The coming days will be clear starting in the afternoon.
Compare today's weather with yesterday's data and track temperature trends over time.
Hourly Forecast
Daylight Hours
06:38
Sunrise
18:50
Sunset
Moon
Waxing Crescent
11:14
Moonrise
20:44
Moonset
Daily Forecast
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Wednesday
Thursday
Friday
Saturday
Sunday
Monday
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Thursday
Air Quality Data Available
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Humidity
Weather in Rancho Cucamonga today, September 15, 2026
Rancho Cucamonga is set for a fine, sunny day on September 15, 2026, with only limited interruptions to the clear sky. The early hours look particularly favourable for being outside. The morning looks comparatively open, with cloud near 49% around 09:00. Early outdoor plans have a better chance of staying dry and bright.
The day peaks near 29°C and cools toward 17°C. The air stays humid, with relative humidity between 36% and 88% and the peak around 23:00. Expect gentle winds, highest near 16:00 at 5.7 km/h.
The afternoon keeps an overcast feel, as cloud reaches about 71% around 23:00. Outdoor plans may still want a flexible backup. Expect visibility near 15.8 km, with poorer spells close to 14.0 km. Daylight runs from 06:38 to 18:50, lasting 12 hours 12 minutes of sunlight today.
In short, September 15, 2026 looks like a fine day in Rancho Cucamonga for being outside, peaking around 29°C.
Frequently asked questions about weather in Rancho Cucamonga
How warm does it get in Rancho Cucamonga?
The warmest month in Rancho Cucamonga is August, with average high temperatures of 34°C. The average temperature during this period is around 26°C.
How cold does it get in Rancho Cucamonga?
The coldest month in Rancho Cucamonga is January, with average low temperatures of 6°C. The average temperature during this period is around 11°C.
What is the wettest time of year in Rancho Cucamonga?
The wettest month in Rancho Cucamonga is January, with an average of 103mm of precipitation.
What is the driest time of year in Rancho Cucamonga?
The driest month in Rancho Cucamonga is July, with an average of 1mm of precipitation.
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