What to wear to Portola Festival: San Francisco sits at 21°C (70°F) by day and 14°C (57°F) at night in September, on city streets, with a low chance of rain. That means a light base with one warm layer you can carry, cushioned trainers or a low boot, and a bag small enough for the gate rules. The crowd leans techno, house and urban, so black and functional reads as insider.
Women's outfits at Portola Festival have to clear the same three hurdles as everyone else's. 21°C (70°F) by day, 14°C (57°F) at night, city streets underfoot, with more options for solving them.
The dominant aesthetics at Portola Festival are techno black, house, urban and underground. That is the visual language of the site, the stages, the merch, the crowd photos, and outfits that speak it look intentional rather than borrowed.
This is a function-first crowd. Black, utility and good shoes read as insider; heavy glitter and fancy dress read as tourist. Nobody is stopping you, but you will feel it.
What people actually wear: one good layer over a light base, because the temperature halves after sunset.