SAN BERNARDINO (CBS) — Fire danger in the Angeles National Forest has been increased from “high” to “very high” over the Labor Day weekend, according to the U.S. Forest Service.

“The grass is dried out and . . . there is still potential for fire in the light, grassy fuels. The fires will burn a lot faster,” Capt. Adrian Murrieta said.

The Forest Service says extreme heat is expected over the weekend, but open wood and charcoal fires are still allowed in designated areas.

“Campgrounds, picnic areas that have rings developed for that reason,” said Nathan Judy of the Forest Service.

As a precaution, crews have cleared brush in some areas.

Nearly all campsites in the park will be open over the holiday weekend.