Sammamish Weather in September

What's the weather like in Sammamish (Washington) in September 2024?

The climate in Sammamish during September can be summarized as mild and reasonably dry.

September is in the fall / autumn in Sammamish and is typically the 4th warmest month of the year. Daytime maximum temperatures average around 20°C (69°F), whilst at night 10°C (50°F) is normal.

Sammamish weather averages (imperial / metric)
Daytime temperature 20.3°C 68.5°F
Nightly temperature 9.7°C 49.5°F
Average temperature 15°C 59°F
Daily sunshine 7.8 hrs
Avg rainfall 66 mm 2.6 ins
Rainy days 9 days
Sea temperature 12.8°C 55.1°F
Humidity 72%
Windspeed 11.9kph 7 mph

On average September is the 4th driest month of the year in Sammamish with around 66mm 2.6 inches of rain making it a reasonably dry time to visit. This rainfall is typically spread over 9 days, although this may vary considerably.

On the flip side this corresponds to an average of 7.8 hours of sunshine per day.

September temperatures in Sammamish

Sammamish average temperature in September

September rainfall

Sammamish average rain in September

September hourly sunshine

Sammamish average rain in September

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 Sammamish in September 2024.