The arrival of September means the start of summer proper in San Francisco, when the gloom of June and July gives way to unambiguously warm days and topaz skies. So there's no better time for the Rock Make festival, a gathering of local craft vendors and some of the region's best independent musicians, put on by local music site the Bay Bridged. This year's musical highlights include the out-there poptronica of Yalls (aka Berkeley sample/synth wizard Dan Casey), the literate folk-rock of John Vanderslice, and the jazzy world-pop of promising new group DRMS. These artists and many more perform at a stage on a Mission street, alongside food trucks and local craftspeople, for a decidedly summery party this weekend. And since it's September, there might even be blue skies.