Answer:
Due to direct sunlight.
Step-by-step explanation:
Rancho Cucamonga has a hot climate in August because the sunlight occurs directly on the Rancho Cucamonga area which is the main cause of hot weather. There is very little rainfall occurs in Rancho Cucamonga region about 427 mm which shows a semi arid climate. It has a desert climate which is the main cause of hot climate in the month of August.