The fire danger level will be raised from "high'' to "very high'' Sunday in the Angeles National Forest as the mercury rose from below average to above average over the weekend.
The change in alert status comes as vegetation continues to dry out and "the region has seen a marked increase in fire activity,'' Stanton Florea of Angeles National Forest said earlier.
"Grasses growing below 4,500 feet elevation have cured and are especially prone to fire,'' Florea said.
Since May 17, when the fire danger level was raised to "high,'' 79 wildfires have occurred in and around the Angeles National Forest, with the two largest fires occurring over the past two weeks, he said.
Summer recreational activities that bring more than a million visitors a year to the Angeles National Forest are factored into the fire danger level because 91 percent of all wildfires in the forest are caused by humans, Florea said.
Open wood and charcoal fires will only be allowed in developed campgrounds and picnic areas where fire rings and grills are provided.
Gas- and propane-powered stoves and grills are permitted in backcountry areas with a valid California Campfire Permit, which is available free of charge at all U.S. Forest Service offices and most visitor centers and fire stations, Florea said.
Spark arrestors should be checked to make sure they are in good working order on all off-road vehicles, chain saws and other equipment with internal combustion engines, Florea said.
All fireworks are prohibited on national forest lands.
Forest visitors are "urged to use common sense'' and to maintain a higher level of awareness with the increased fire risk.
"Travelers through the forest should remain on designated roads and never park on dry brush or grass,'' Florea said.