See exactly when rain will start and stop with a minute-by-minute precipitation nowcast for the next hour.
14°
Foggy
Feels Like: 13°
Min: 13°
Max: 17°
The next few hours will be foggy, with today reaching 17°C and dropping to 14°C. The coming days will be clear from afternoon until night.
Compare today's weather with yesterday's data and track temperature trends over time.
Hourly Forecast
Daylight Hours
06:58
Sunrise
19:09
Sunset
Moon
Waxing Crescent
12:48
Moonrise
21:28
Moonset
Daily Forecast
Today
Thursday
Friday
Saturday
Sunday
Monday
Tuesday
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Friday
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Weather in Mill Valley today, September 16, 2026
Mill Valley starts September 16, 2026 under largely sunny skies, with bright spells setting the tone from the outset. Outdoor plans should enjoy long stretches of open sky as the day unfolds. Expect a grey start, with morning cloud around 100% by 03:00. Outdoor plans early on should not rely on bright skies.
Temperatures climb from an overnight low near 13°C toward a daytime high of about 17°C. Relative humidity sits between 81% and 100%, reaching its peak around 03:00. Expect gentle winds, highest near 15:00 at 7.9 km/h.
Afternoon skies stay clogged, peaking close to 100% near 19:00. The grey theme continues rather than clearing out. Visibility holds near 10.5 km, though it can fall to 0.1 km. Daylight runs from 06:58 to 19:09, lasting 12 hours 11 minutes of sunlight today.
In short, September 16, 2026 looks like a fine day in Mill Valley for being outside, peaking around 17°C.
Frequently asked questions about weather in Mill Valley
How warm does it get in Mill Valley?
The warmest month in Mill Valley is September, with average high temperatures of 24°C. The average temperature during this period is around 18°C.
How cold does it get in Mill Valley?
The coldest month in Mill Valley is December, with average low temperatures of 7°C. The average temperature during this period is around 10°C.
What is the wettest time of year in Mill Valley?
The wettest month in Mill Valley is January, with an average of 125mm of precipitation.
What is the driest time of year in Mill Valley?
The driest month in Mill Valley is July, with an average of 0mm of precipitation.
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