A brush fire spread to more than 250 acres in windy conditions Wednesday afternoon in the Hesperia area in San Bernardino County.
The fast-moving fire was threatening structures in its early stages, but that threat had decreased by Thursday morning, firefighters said. Details about how the fire started were not immediately available.
Containment is at 30 percent.
Wind gusts topped 30 mph, CALFIRE said.
A red flag fire weather warning was in effect Wednesday for most of eastern California. An excessive heat watch is in effect for San Bernardino County.
More than 2,700 wildfires have been reported in California through the start of June. That figure was at 2,025 for the same period last year.
Fires have burned 12,540 acres this year, doubling the number of acres burned from the start of 2020 through June of last year.
The state's five-year average for that time period is 1,615 fires and 10,538 acres.