Over 12,000 firefighters are battling 18 active wildfires across California.

Spokesman Daniel Berlant of Cal Fire said they are making headway.

“After Tuesday, temperatures are predicted to decrease back to a more seasonable normal level. Winds in many parts of Northern California will continue at lighter speeds early in the week with very low humidity,” he said.

In Southern California westerly winds of 15 to 25 mph with gusts to 40 mph will surface across the Tehachapi Mountains, Antelope Valley, and Banning Pass.

“While temperatures will begin to be cooler statewide, very warm and dry conditions will maintain an elevated threat for large fires across the foothills and mountains,” Berlant said.

A growing problem in California, he added, is hobby drones, or (UAS) unmanned aircraft system, interfering with the air operations over wildfires. A collision with a hobby drone could easily result in major damage to firefighting aircraft, injuries to the pilot and crew on board as well as firefighters below, and/or worse, a midair collision. It is unsafe for unauthorized drones to be flown anywhere near a wildfire. Cal Fire officials stress to hobby drone users, “If you fly, we can’t!” and Berlant said drones should not be flown anywhere near a firefighting effort.

Fires of interest as of press time Aug. 18 included:

Cal Fire incidents

Jerusalem Fire, Lake and Napa counties: 25,118 acres – 95 percent contained with all evacuations lifted

Humboldt Lightning Fires, Humboldt County: 75 fires totaling 4,883 acres – 97 percent contained

Mark Fire, Calaveras County, South of Angels Camp: 114 acres – 100 percent contained.