Mill Valley in December
Not the best time
December brings the wet season in earnest with frequent rains and cool temperatures. Perfect for cozy getaways and holiday celebrations, but outdoor enthusiasts should wait for drier months.
Weather
December brings full winter weather with cool days in the upper 50s and chilly nights around 40°F. Rain becomes frequent with storms arriving every few days. The hills stay green, but hiking conditions become challenging.
15°C high5°C low10 rain days
Crowds & Cost
low crowds
~$200/day average
Events & Festivals
- •Holiday lights on Miller Avenue
- •Winter solstice gatherings
- •New Year's Eve celebrations at local venues
December Tips
- •Book holiday dinners early at popular spots like Avatar's Restaurant
- •Muddy trails make hiking boots essential
- •Great time for spa visits and indoor activities
All Months
April through October gives you the best weather in Mill Valley. Summer means no rain but also means fog that rolls in most afternoons — pack layers even in July. May and September hit the sweet spot with warm days and clear skies. The Mill Valley Film Festival happens in October, bringing crowds and higher hotel rates. Winter brings rain that can last for days, but also fewer tourists and green hills that photographers love. Spring wildflowers bloom best in March and April along the Dipsea Trail. Avoid Memorial Day and Labor Day weekends unless you enjoy fighting for parking spots.
Mill Valley Scores
Solo
6/10
Couples
7/10
Families
8/10
Adventure
6/10
Budget
4/10
Luxury
6/10
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