Sunnyvale Weather in October

The climate in Sunnyvale during October can be summarized as mild and dry.

October is in the fall / autumn in Sunnyvale and is typically the 5th warmest month of the year. Daytime maximum temperatures average around a comfortable 23°C (74°F), whilst at night 10°C (50°F) is normal.

On average October is the 6th driest month of the year in Sunnyvale with around 22mm 0.9 inches of rain making it a dry time to visit. This rainfall is typically spread over 4 days, although this may vary considerably.

On the flip side this corresponds to an average of 9 hours of sunshine per day.

The data used in these monthly averages covers a period of over 100 years right up until last year. As such they are a valid prediction of what to expect for the weather in Sunnyvale in October 2025.