Southern Californians welcomed cooler temperatures and spotty rain Saturday from a tropical storm veering off the Pacific coast days after a relentless heat wave nearly overwhelmed the state’s electrical grid. Officials braced for flooding in coastal and mountain areas from the storm and feared powerful winds could expand the massive Fairview Fire about 75 miles (121 km) south-east of Los Angeles. But minimal flooding was reported early Saturday and crews made significant progress on the fire and said they expected full containment on Monday. More than 10,000 homes and other structures were threatened by the blaze. The National Weather Service forecast an end to the grueling heatwave in the Los Angeles area Saturday though heat and wind advisories remained in effect through the evening, and warned of possible flooding in mountain areas and some beach communities. In San Diego county, inland areas such as Mt Laguna and Julian received several inches of rain while coastal communities got less than an inch, the National Weather Service reported. With flooding possible, officials in coastal cities posted warning signs and made sandbags available to the public. In Orange county’s Seal Beach, a beach parking lot had minor flooding Friday from the high tide, authorities said. Firefighters had feared powerful winds that topped 100mph (161 km/h) could expand the massive Fairview fire burning about 75 miles (121km) southeast of Los Angeles, but instead crews made significant progress and pegged Monday as a day when they should have full containment. More than 10,000 homes and other structures remained threatened and evacuation orders were still in place. Hurricane Kay made landfall near Mexico’s Bahia Asuncion in Baja California Sur state Thursday, but it quickly weakened into a tropical storm by the time it reached southern California. Still winds, were ferocious in places – speeds reached 109mph on San Diego County’s Cuyamaca Peak, the National Weather Service said. The tropical conditions added a swelter to the heat wave that saw temperatures soar past 100F (38C) in many parts of California this week. Even places like San Diego, renowned for its temperate climate, baked in the heat. By late morning Friday a steady rain pelted downtown San Diego as Charles Jenkins swept the accumulating puddles away from the tarps of his makeshift home. “The heat was killer, so for now this feels good,” Jenkins said. “I just hope the water doesn’t get too high. But I will rough it. I’ve got pallets I can put underneath to keep out the rain.” Though rainfall generally was moderate across Southern California Friday there was a chance of isolated thunderstorms and heavy downpours into Saturday. With flooding possible, officials in coastal cities posted warning signs in low-lying areas and made sandbags available to the public. September already has produced one of the hottest and longest heatwaves on record for California and some other Western states. Nearly 54 million people were under heat warnings and advisories across the region this week as temperature records were shattered in many areas. Scientists say climate change has made the West warmer and drier over the last three decades and will continue to make weather more extreme and wildfires more frequent and destructive. In the last five years, California has experienced the largest and most destructive fires in state history. While firefighters made progress against the Fairview Fire, the fast-moving Mosquito Fire in the foothills east of Sacramento doubled in size Friday to at least 46 square miles (119 square kilometers) and threatened 3,600 homes in Placer and El Dorado counties, while blanketing the region in smoke. Flames jumped the American River, burning structures in the mountain hamlet of Volcanoville and moving closer to the towns of Foresthill, home to about 1,500 people, and Georgetown, population 3,000. More than 5,700 people in the area have been evacuated, said Placer County Sheriff’s Office Lt Josh Barnhart.