In a phone call with SFGATE, National Weather Service Gulf Coast Meteorologist Rick Canepa said three different Bay Area cities set or reached their all-time highs for September. In Gilroy, the temperature reached 112 degrees, matching the previous September high. In Santa Rosa, the mercury also rose to 112, breaking the previous September high. And in Livermore, the temperature was recorded at 116 degrees — the highest the National Weather Service has ever recorded anywhere in the Bay Area. To cool off during the heat wave in the San Francisco Bay Area, people enjoy playing in the water at Sausalito Beach in Sausalito, California on September 5, 2022.Douglas Zimmerman/SFGATE That 116 mark also stood in Fairfield, according to San Francisco Chronicle meteorologist Gerry Diaz. (SFGATE and the San Francisco Chronicle are both owned by Hearst but operate independently of each other.) Many records were set today in the Bay Area, including several new daily high temperature records, a few September monthly records and an all-time record. #cawx pic.twitter.com/zsYDQJgpXX — NWS Bay Area 🌉 (@NWSBayArea) September 6, 2022 While the Bay Area has been bracing for an extraordinary heat wave over the past few days, temperatures on Monday were even hotter than many expected. “It could have been warmer in some locations than people predicted,” Canepa said. Central San Francisco (which is now under a heat advisory) reached 91 degrees Monday, not close to September’s record of 106 degrees. In Oakland, the temperature soared to 100 degrees, nine degrees shy of September’s all-time high. And tomorrow may be just as hot. To cool off during the heat wave, people flock to Sausalito Beach in Sausalito, California on September 5, 2022. Douglas Zimmerman/SFGATE “You would expect warm to very warm (temperatures tomorrow) with many places reaching or exceeding 100 degrees. Conditions are forecast to be much the same as today,” Canepa said. At least near the coast, temperatures may drop a bit on Wednesday. But further inland, the highs could last longer. The heat is expected to subside across the Bay Area by the weekend. To cool off during the heat wave, people pack Sausalito Beach in Sausalito, California on September 5, 2022. Douglas Zimmerman/SFGATE To cool off during the heat wave in the San Francisco Bay Area, people pack Sausalito Beach in Sausalito, California on September 5, 2022. Douglas Zimmerman/SFGATE