What's happening in San Francisco this week?

San Francisco's week starts cold and gray. Monday mornings the fog sits thick over the Marina District, humidity near 100%, temperatures around 12-13°C until roughly 11am. The smell of damp eucalyptus drifts off the Presidio trails. Monday is also closure day for the de Young Museum in Golden Gate Park and the Asian Art Museum in the Civic Center, so treat it as a walking day. Head to Lands End Trail on the northwest corner, where you'll hear foghorns from the Golden Gate Bridge mixing with the crash of surf against the rocks below Mile Rock Beach. The path runs 2.6 km from the Sutro Baths ruins to Eagle's Point, and on a Monday morning you might pass 15 people total.

Tuesday shifts the rhythm. The Ferry Building Farmers Market opens at 10am on the Embarcadero waterfront, smaller than Saturday's version but with shorter lines at Boccalone's salumi counter and Cowgirl Creamery's Mt. Tam triple-cream samples. By midday Tuesday through Thursday, the fog has typically burned back to a bright white ceiling over Ocean Beach while the eastern neighborhoods (the Mission, SoMa, Potrero Hill) sit in full sun at 18-21°C. Wednesday and Thursday evenings the Mission District between 16th and 24th Streets fills with dinner crowds. The warm corn tortilla smell from La Palma Mexicatessen on 24th near Florida Street is stronger than any restaurant sign.

Saturday is the big day. The Ferry Building market runs 8am to 2pm with over 100 vendors, and by 9:30am the line at Blue Bottle's kiosk stretches 20 people deep. Golden Gate Park's western half near the Dutch Windmill stays quiet until 10am while the eastern end around the California Academy of Sciences (opened 1853, current building from 2008) fills with families. If you want the Golden Gate Bridge walkway without shoulder-to-shoulder foot traffic, Saturday before 8am or any weekday morning works. The bridge sidewalk opens at 5am for pedestrians on the east side. Sunday morning Golden Gate Park closes JFK Drive to cars, and the road fills with cyclists and roller skaters between 6am and 6pm. Porta Portese-style, the Alemany Flea Market opens Sunday at 100 Alemany Boulevard from 7am to 3pm. Arrive by 8am for the best vintage finds.

The weather rhythm matters more here than in most American cities. June through August, the western neighborhoods (Sunset, Richmond, Outer Parkside) can sit 8-10°C cooler than the Mission or Dogpatch on the same afternoon. The fog pattern runs roughly 3-day cycles in summer, with 2 foggy mornings followed by 1 clearer day. Pack layers regardless of what your phone says about 'San Francisco weather' because microclimates shift block by block. That 21°C reading in Dolores Park at 2pm means 13°C and wind at Ocean Beach, a 25-minute bus ride away on the N-Judah line.