High surf advisories are in effect through Saturday at 5 p.m. due to a southerly swell fueled by Tropical Storm Genevieve, creating 4- to 8-foot breaking waves, sets exceeding 9 feet, and dangerous rip currents. Extreme heat and high surf will dominate Southern California over the weekend as a dome of high pressure hovers over the region. What we know:The National Weather Service warned of "dangerously hot" temperatures and has issued Heat Advisories and Extreme Heat Warnings for most of the region. High Surf and High TidesA high surf advisory is in effect due to a southerly swell driven by energy from Tropical Storm Genevieve, a former hurricane weakening off the coast. Large breaking waves between 4 and 8 feet are expected, with sets beyond 9 feet possible alongside dangerous rip currents.