Rapidly Spreading California Wildfire Destroys 10 Structures

A rapidly growing wildfire in California near Yosemite National Park destroyed 10 structures overnight on Friday and threatened 2,000 more, the authorities said.

The fire, called the Oak fire, began at 2 p.m. on Friday afternoon in Midpines in Mariposa County, roughly 70 miles north of Fresno and about 10 miles from Yosemite near the Sierra Nevada foothills. The fire grew overnight to 6,555 acres, or more than 10 square miles, according to a report from CalFire, the state’s fire agency. By 11 p.m. on Friday, the it had covered a little over 4,000 acres.

The fire’s “explosive nature” has posed a challenge to the 400 firefighters and four helicopters that were deployed, CalFire said. On Saturday morning, the fire was zero percent contained, the agency said in an update. Natasha Fouts, a spokeswoman for CalFire, said that this was the fastest growing fire of the season so far, surpassing the speed of the Washburn fire that continued to burn in Yosemite National Park.

On social media, residents shared images of an ominous plume of smoke that quickly overtook an orange and red sky after the fire began.

Evacuation orders were issued for an area stretching several miles away from the fire, and officials closed multiple roads. It was not known if any residents had suffered injuries. An American Red Cross station was opened at the Mariposa Elementary School. In addition to the structures that were destroyed, five others were damaged.

Fire officials did not expect to contain the fire until next week, Ms. Fouts said.

While wildfires occur throughout the West every year, the link between climate change and bigger fires is inextricable. Wildfires are increasing in size and intensity in the Western United States, and wildfire seasons are growing longer. Recent research has suggested that heat and dryness associated with global warming are major reasons for the increase in bigger and stronger fires.

“The heating of the planet is turning landscapes into tinderboxes,” said a report published in February by climate scientists in the United Nations Environment Program.

Experts have said that this might be one of the most brutal fire years in the state, since California is in the midst of a severe drought and the summer has been extremely hot. Those conditions made the last two fire seasons particularly destructive, together killing a total of 36 people and destroying more than 14,700 buildings in the state.

The cause of the Oak fire is still under investigation, but a report issued Friday night said that vegetation in the area was “very receptive to new spot fires due to the hot, dry weather and drought,” and that heavy fuels, strong winds and low humidity were also influencing fire behavior. The entire county of Mariposa is enduring a drought, according to the National Integrated Drought Information System, a government agency, and this is the driest year on record for the county.