California was hit by nearly 11,000 lightning strikes in 72 hours, sparking 367 fires, nearly two dozen of them major, as the state suffered a record heat wave, authorities said.
Governor Gavin Newsom has declared an emergency over the fires and said he has requested 375 fire engines from out of state with Arizona, Nevada and Texas sending assistance.
"We are experiencing fires the likes of which we haven't seen in many, many years," Newsom told a news conference.
A group of fires called the SCU Lightning Complex about 20 miles (32 km) east of Palo Alto more than doubled in size overnight and is now burning over 85,000 acres. The CZU August Lightning Complex has grown to over 10,000 acres and forced evacuations around 13 miles (21 km) south of the city.