Fort William Weather in September

The climate in Fort William during September can be summarized as mild and very wet.

September is in the fall / autumn in Fort William and is typically the 4th warmest month of the year. Daytime maximum temperatures average around a cool 14°C (56°F), whilst at night 7°C (44°F) is normal.

On average September is the 5th wettest month of the year in Fort William with around 272mm 10.7 inches of rain making it a very wet time to visit. This rainfall is typically spread over 23 days, although this may vary considerably.

On the flip side this corresponds to an average of 3 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 Fort William in September 2025.