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The weather in Rancho Cucamonga in August is hot. The average temperatures are between 22°C and 32°C.
There shouldn't be any rainy days in in Rancho Cucamonga during August. Having said that, the days are very hot in August so hanging out outside is more recomanded during the after noons and evening time.
Our weather forecast can give you a great sense of what weather to expect in Rancho Cucamonga in August 2025.
If you’re planning to visit Rancho Cucamonga in the near future, we highly recommend that you review the 14 day weather forecast for Rancho Cucamonga before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 19° / 9° | 2 | 29 | 0 | 57 mm | Good | Rancho Cucamonga in January |
| February | 19° / 9° | 2 | 26 | 0 | 63 mm | Good | Rancho Cucamonga in February |
| March | 20° / 10° | 2 | 29 | 0 | 36 mm | Good | Rancho Cucamonga in March |
| April | 22° / 12° | 1 | 29 | 0 | 22 mm | Good | Rancho Cucamonga in April |
| May | 24° / 14° | 0 | 31 | 0 | 7 mm | Perfect | Rancho Cucamonga in May |
| June | 28° / 18° | 0 | 30 | 0 | 1 mm | Perfect | Rancho Cucamonga in June |
| July | 31° / 21° | 0 | 31 | 0 | 10 mm | Good | Rancho Cucamonga in July |
| August | 32° / 22° | 0 | 31 | 0 | 6 mm | Good | Rancho Cucamonga in August |
| September | 31° / 21° | 0 | 30 | 0 | 5 mm | Good | Rancho Cucamonga in September |
| October | 26° / 17° | 1 | 30 | 0 | 10 mm | Perfect | Rancho Cucamonga in October |
| November | 22° / 12° | 1 | 29 | 0 | 22 mm | Good | Rancho Cucamonga in November |
| December | 18° / 9° | 3 | 28 | 0 | 72 mm | Good | Rancho Cucamonga in December |