Ahhh, refreshing coastal weather.
See Also
A Complete Guide to Hiking the John Muir TrailTrek Training | John Muir TrailPasses of the John Muir Trail — Let's Trek ItHike of the Week: John Muir Trail - Part 1The coast redwood forest is cool most times of the year with temperatures ranging from 40 - 70 degrees F or 4 - 21 degrees C. From late October to early May expect rain. Summer months (June-August) can be warmer but it is generally cool and dry. Expect heavy fog in the morning, burning off in the afternoon. Some say fall (August-October) is the best weather of the year. But, don't let the weather stop you from having fun. If you're dressed for the weather and wear sturdy shoes, the giant trees are beautiful all year round.
See Also
3 Best Hikes in Muir Woods