When visitors in other cities swelter in summer's heat and picnic plans are abandoned for air conditioned cafes, San Francisco's typical weather report is like a call to gather up the picnic basket, blanket and head out: "coastal fog reaching into the Bay will burn off by late morning, then clear skies until late afternoon fog rolls in again. Highs in the mid- to upper-60's, lows in the mid-50's."

For a new take on the traditional picnic lunch in the sun, visitors can orchestrate their al fresco dining around San Francisco's fabulous spectacle of summer fog. Fortified with a basket full of gourmet food and drink, a blanket (or two) and warm coats, foggy day picnickers can later brag of the invigorating and unusual experience for years.

Summer fog is common, but not an everyday event, so a bit of spontaneity works in favor of those in pursuit of a fog adventure. Morning and evening fog rolls into San Francisco Bay from June to August, pushing its way through the Golden Gate Bridge towers, drifting and swirling up and over the Marin Headlands, and nestling up against shoreline piers. Then, more often than not, it magically stops before consuming the city itself. It's a picturesque show of nature that changes each day as the elements of the sea, sun and wind interact.

Timing is essential. By mid-day the sun has burned off the white wispy stuff so people shed their jackets and sweaters to bask in the sun before the fog rolls in again by late afternoon.

FOG-FREE AREAS FOR FOG VIEWING PICNICS

Whether one is beside it, above it or in the thick of it, fog is a mystical and magical drama of nature to behold. Here are a few suggestions of where to find fog viewing spots.

Just below the northern end of the Golden Gate Bridge and Vista Point lies East Fort Baker. This secluded recreation area with views of the bay is often sunny when the western park areas are fogged in.

Walk from the nearby Golden Gate Transit bus stop or drive down Bunker Road to East Fort Baker to find this treasure complete with a fishing pier, the innovative Bay Area Discovery Museum, historical brick fortifications of Battery Cavallo and concrete gun emplacements of Battery Yates.

Eye-level views of cargo ships, tankers, luxury liners, yachts and sailboats passing area accented with blasts of a traditional air fog horn from the Golden Gate Bridge which looms almost overhead. The grassy parade grounds and coastal bluffs of East Fort Baker combine to make a protected picnic spot that is out of the wind, but still offers pristine fog bank views.

ABOVE IT ALL

For a heavenly viewpoint, rise above the mist atop a Bay Area hill. Look down upon the shroud of fog as it penetrates the Golden Gate Straight. First as wispy tendrils, then as a blanket of fleece, fog sometimes covers even the tips of the Golden Gate Bridge towers and stretches itself out into the Bay. In the same glance take in the city skyline with the unmistakable silhouettes of Coit Tower and the Transamerica Pyramid reaching upward. Breathtaking is an understatement.

Just 15 minutes north of the Golden Gate Bridge and Marin Headlands, Mt. Tamalpais' summit is less than a half-mile high. But, the mountain rises almost straight up from sea level and offers 360 degree views of the entire Bay Area and west to the Pacific Ocean. On foggy days, the meadows, grasslands, forests and creeks at lower elevations are sometimes enveloped in a dreamlike fog, yet other peaks are visible just above. The park has numerous parking areas, trailheads, scenic overlooks and two drive-in picnic areas with day-use facilities.

The 20-minute descent on West Ridgecrest Boulevard on the northern flank of "Mt. Tam" affords a great road for a sunset drive when the fog is in.

Across the bay and atop the Berkeley-Oakland Hills lies Tilden Regional Park. Magnificent views are the reward for ascending the Sea View Trail. Eucalyptus and Monterey pine trees line the trail that runs south from Inspiration Point off Wildcat Canyon Road and can be reached by car or AC Transit from the Berkeley BART station.

The weather at Angel Island, Sausalito and Alcatraz isn't as predictable for fog fans; they can be terrific view spots or be totally socked in. However, bay cruise companies offer a choice of destinations and can usually give sure-fire suggestions for getting into or out of a fog bank.

IN THE THICK OF IT

When the tide of fog is in, a walk across the Golden Gate Bridge is for the hearty and adventurous. The Marin Headlands are equally fog-saturated. Along Crissy Field, the Golden Gate Promenade, Marina Green and Fisherman's Wharf, the wetness and wind may be a bit less chilling, but bundle up and bring the hot chocolate.

FUN FOG FACTS