A wildfire in Yosemite National Park flared up on Sunday night, forcing helicopter evacuations of around 100 visitors of the California park.

The fire has been burning for several weeks in the backcountry of the famed national park, but high temperatures and strong winds fueled the flames and endangered hikers and campers, according to a report from The Wall Street Journal.

Yosemite spokeswoman Kari Cobb said many of those evacuated were hikers who had reached the summit of the iconic Half Dome. Other evacuees were at campsites and on walking trails. The park has kept roads open, but many trails were closed in response to the growing fire.

Firefighters had been keeping an eye on the blaze, which started from a lightning spark between Little Yosemite Valley and Half Dome. But the hot and windy Sunday made the fire much more dangerous.

"We just got unbelievable crazy winds and unexpected hot conditions," said Tim Ludington, the park's chief of roads and trails. "The fire behavior totally changed."

The fire has burned at least 700 acres and firefighters have yet to establish any sort of containment on the blaze because of harsh terrain in Yosemite.

Firefighters elsewhere in California have their hands full with two other major blazes. California has been in a severe drought with fires starting much more easily than under normal conditions.

Around the town of Mariposa, about 15 miles from Yosemite, firefighters have been batting a 300-acre fire and have established 70 percent containment. The California Department of Forestry and Fire Protection has lifted an evacuation order on about 300 homes in the area, The Weather Channel reported.

That fire broke out Friday afternoon, and a total of 700 homes and five businesses were at risk.

Another fire, in the Northern California county of Siskiyou, has burned 151 square miles and is only 30 percent contained. The Forest Service said $54.7 million has been spent and 2,700 people have worked to fight the fire.