National Weather Service Forecast for: Rancho Cucamonga CA
Issued by: National Weather Service San Diego, CA
Updated: 12:14 pm PDT Apr 6, 2026
 
This
Afternoon
This Afternoon: Sunny, with a high near 81. Southwest wind 10 to 15 mph, with gusts as high as 20 mph.
Sunny
 Tonight

Tonight: Mostly clear, with a low around 56. Southwest wind 5 to 10 mph becoming light west in the evening. Winds could gust as high as 20 mph.
Mostly Clear
 Tuesday

Tuesday: Sunny, with a high near 81. Light west wind becoming southwest 5 to 10 mph in the afternoon. Winds could gust as high as 20 mph.
Sunny
 Tuesday
Night
Tuesday Night: Mostly clear, with a low around 57. Southwest wind 5 to 10 mph becoming light west in the evening.
Mostly Clear
 Wednesday

Wednesday: Sunny, with a high near 81. Light west wind becoming southwest 10 to 15 mph in the afternoon. Winds could gust as high as 20 mph.
Sunny
 Wednesday
Night
Wednesday Night: Increasing clouds, with a low around 58.
Increasing
Clouds
 Thursday

Thursday: Partly sunny, with a high near 78.
Partly Sunny
 Thursday
Night
Thursday Night: Mostly cloudy, with a low around 55.
Mostly Cloudy
 Friday

Friday: A slight chance of showers after 11am. Mostly sunny, with a high near 75.
Slight Chance
Showers
Hi 81 °F Lo 56 °F Hi 81 °F Lo 57 °F Hi 81 °F Lo 58 °F Hi 78 °F Lo 55 °F Hi 75 °F

 

This Afternoon
 
 Sunny, with a high near 81. Southwest wind 10 to 15 mph, with gusts as high as 20 mph.
Tonight
 
 Mostly clear, with a low around 56. Southwest wind 5 to 10 mph becoming light west in the evening. Winds could gust as high as 20 mph.
Tuesday
 
 Sunny, with a high near 81. Light west wind becoming southwest 5 to 10 mph in the afternoon. Winds could gust as high as 20 mph.
Tuesday Night
 
 Mostly clear, with a low around 57. Southwest wind 5 to 10 mph becoming light west in the evening.
Wednesday
 
 Sunny, with a high near 81. Light west wind becoming southwest 10 to 15 mph in the afternoon. Winds could gust as high as 20 mph.
Wednesday Night
 
 Increasing clouds, with a low around 58.
Thursday
 
 Partly sunny, with a high near 78.
Thursday Night
 
 Mostly cloudy, with a low around 55.
Friday
 
 A slight chance of showers after 11am. Mostly sunny, with a high near 75.
Friday Night
 
 A slight chance of showers and thunderstorms, then a chance of showers after 11pm. Mostly cloudy, with a low around 54.
Saturday
 
 Showers likely and possibly a thunderstorm. Mostly cloudy, with a high near 66.
Saturday Night
 
 A chance of showers. Mostly cloudy, with a low around 52.
Sunday
 
 A slight chance of showers. Partly sunny, with a high near 66.

 

Forecast from NOAA-NWS for Rancho Cucamonga CA.