Portland Weather in September

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

September is in the spring in Portland and is typically the 4th coldest month of the year. Daytime maximum temperatures average around a cool 15°C (60°F), whilst at night 8°C (46°F) is normal.

On average September is the 5th wettest month of the year in Portland with around 77mm 3 inches of rain making it a reasonably dry time to visit. This rainfall is typically spread over 10 days, although this may vary considerably.

On the flip side this corresponds to an average of 5.9 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 Portland in September 2024.