Mill Valley Weather in September

Mill Valley in September sees high temperatures, with highs around 24°C (75°F) and overnight lows of 12°C (54°F). With just 5 mm (0.2 in) of rainfall on average, rain is rarely an issue.

Rainfall in Mill Valley in September

Climate statistics over the past 30 years suggest around 2 days of rain, with 5 mm (0.2 in) average for the month. The occasional light shower is possible, but rain is rarely an issue this month.

Temperature in Mill Valley in September

Mill Valley has excellent weather in September, with days reaching 24°C (75°F) and nights cooling to 12°C (54°F). The days can feel warmer than the evenings, so packing for both parts of the day is a good idea. With lows of 12°C (54°F), nights are cool. If you're out after dark, an extra layer will keep you comfortable. The cooler air at night is also great for getting a good rest. On average, it is the month with the highest temperature of the year.

Sunshine in Mill Valley in September

Expect sunny days throughout the month, with an estimated 270 hours of sunshine. This makes it a pleasant time to visit Mill Valley.

If you favor pleasant temperatures and minimal rainfall, September is one of the best months to visit Mill Valley.