braced for more lightning storms on Monday that could supercharge massive wildfires burning across an area three times the size of Los Angeles, according to Reuters. The worst of the wildfires, including the second and third largest in California history, were around the San Francisco Bay Area which was under a red flag warning for dry-lightning and gusty, erratic winds, the National Weather Service said. "The threat of a thunderstorm over a fire area is dangerous, let alone over the second and third largest in California history," Brice Bennett, a spokesman for the California Department of Forestry and Fire Protection said of the two largest blazes, the LNU and SCU Lightning Complexes. The fires, which were ignited by over 13,000 lightning strikes from dry thunderstorms across Northern and Central California, have killed at least seven people and destroyed over 1,200 homes and other structures. Smoke from wildfires that have burned over 1.2 million acres created unhealthy conditions for much of northern California and drifted as far away as Kansas. Around 240,000 people are under mandatory evacuation orders, or evacuation warnings, as the fires burn close to Bay Area communities as large as Santa Cruz, with around 65,000 residents. The LNU Complex, which began as a string of smaller fires that merged into one, has burned around 350,000 acres of Napa, Sonoma, Lake, Yolo and Solano counties, Cal Fire said. It was 22% contained as of Monday while to the south the SCU Lightning Complex was nearly as large, at 347,000 acres, and only 10% contained. Another blaze threatened forests south of San Jose with the University of California at Santa Cruz under mandatory evacuation along with dozens of communities. Over 14,000 firefighters are on the wildfires which U.S. President Donald Trump declared a major disaster, freeing up federal funds to help residents and businesses.