Weather in September 2025

Sunnyvale weather in September 2025

°C °F

The average weather in Sunnyvale in September

The temperatures in Sunnyvale in September are comfortable with low of 15°C and and high up to 28°C.

You can expect up to 3 rainy days in Sunnyvale during the month of September.

Our weather forecast can give you a great sense of what weather to expect in Sunnyvale in September 2025.

If you’re planning to visit Sunnyvale in the near future, we highly recommend that you review the 14 day weather forecast for Sunnyvale before you arrive.

Temperatures
28° / 15°
Rainy Days
0
Snowy Days
0
Dry Days
30
Rainfall
6
mm
Sun Hours
11.9
Hrs

Explore the weather in Sunnyvale in other months

Sunnyvale annual weather

Month Temperatures Rainy Days Dry Days Snowy Days Rainfall Weather More details
January 16° / 7° 5 27 0 107 mm
Good
February 16° / 7° 4 24 0 94 mm
Good
March 17° / 7° 5 26 0 92 mm
Good
April 20° / 8° 2 28 0 40 mm
Good
May 22° / 10° 1 30 0 17 mm
Good
June 26° / 13° 0 30 0 6 mm
Perfect
July 28° / 14° 0 31 0 3 mm
Perfect
August 28° / 15° 0 31 0 2 mm
Perfect
September 28° / 15° 0 30 0 6 mm
Perfect
October 24° / 13° 1 30 0 30 mm
Perfect
November 19° / 10° 3 27 0 58 mm
Good
December 15° / 7° 5 26 0 90 mm
Good

Weather in Sunnyvale in September - FAQ

What is the average temperature in Sunnyvale in September?
The average temperature in Sunnyvale in September is 15/28° C.
What is the chance of rain in Sunnyvale in September?
On average, there are 0 rainy days in Sunnyvale during September.
Weather wise, is September a good time to visit Sunnyvale?
The weather in Sunnyvale in September is perfect.
Can it snow in Sunnyvale in September?
On average, there are 0 snowy days in Sunnyvale in September.
More about the weather in Sunnyvale