After 10 days of temperatures in the three digits, the San Francisco Bay Area welcomes back the fog. 
She dropped our temperatures as much as 30 degrees! Tourist or local, one of the best places to appreciate the advantages of the fog-sun summer mix is in Marin County's bohemian Mill Valley, typically in the '70s by day and the upper 50s-60s by night (but in early July sweltering near 100 degrees).
This is the way it works. Summer days in Marin County are typically glorious -- on average lingering in the 80s at the hottest and without much humidity (at least by East Coast standards). 
Mill Valley, situated closer to the ocean than some areas of the North Bay, gets a little more fog in the evenings and mornings, seen as nature's air-conditioning. When womentravelers set out on their morning hike, they're likely to experience cool fog and winds like this.
But the gloom usually clears up by late morning -- and, if it holds, sunshine is always just a few miles north. None of this should be much of a surprise to anyone familiar with Cape Cod. In fact, part of the charm for the cooler, but usually sunny summertime in Mill Valley is its East Coast look. If you blinked, you’d think you were back in New England or in western Cape Cod from Woods Hole to Falmouth.
Originally Mill Valley received visitors by train escaping foggy summers in 
San Francisco, and now they arrive by car. Positioned at the foot of Mount Tamalpais, the half-mile-high summit that presides over Marin County north of San Francisco and the Golden Gate Bridge, Mill Valley was once the depot for the now-defunct Mount Tam Railway. Its polyglot spirit comes from the nature-lovers, artists, intellectuals and vintage ‘60s hipsters who enjoy the remoteness of the shrouded redwood canyons, yet turn out en force for the coffee shops, gourmet wonder Mill Valley Market and chic-chic clothing shops.
On the smug side of welcoming, Mill Valley clearly wants to preserve its privacy, local character and individualism. That doesn't mean that a womantraveler can't be comfortable here. Long a place of creativity, the original stores for Banana Republic and Smith & Hawken are located near the village square (and one of Smith & Hawken's newest stores is located a couple of miles east on Highway 101). Other local faves -- independent bookstore Depot Bookstore & Cafe and original live music club Sweetwater Saloon, home to a host of legends (such as John Lee Hiatt, Boz Scaggs and Jerry Garcia) and young artists for the past 30 years. The Mill Valley Film Festival is a draw for independent filmmakers every fall.
With its slopes outlining the profile of a sleeping Indian maiden, "Mt. Tam" is the center of Marin County hiking and towers over the Pacific coast. The 6000-acre Mt. Tamalpais State Park connects with Golden Gate National Recreation Area and the redwood haven of Muir Woods. In the spring, hiking brings sensational waterfalls.
Shopping best in show:
Summer House Gallery (homestyle and gifts), 21 Throckmorton Ave., 415.383.6695
Tamalpais General Store (gifts), 23 Throckmorton Ave., 415.388.7437
Greenwood Gifts and Furniture (California Craftsman style), 32 Miller Ave., 415.389.5037
Restaurants:
Buckeye Roadhouse (the hottest resto in Southern Marin)
Frantoio (Italian)
Bungalow 44 (sister of the Buckeye)
Ora (Pan-Asian)
Champagne French Bakery Cafe (French)
Lodging:
Acqua Hotel (contemporary)
Mill Valley Inn (quaint)
Mountain Home Inn (in the hills)
