The Lucas Fire burning across Lake and Mendocino counties in Northern California has scorched 4,109 acres, while evacuation orders and warnings remain in force for communities near the blaze.
The fire was 25% contained as of Sunday evening, according to the latest information published by the California Department of Forestry and Fire Protection.
Authorities said cooler temperatures and lighter winds had helped firefighters make significant progress. However, the fire remains active in remote and rugged terrain near the Mendocino National Forest.
Firefighters strengthen containment lines
Crews are working to reinforce existing containment lines, extinguish hot spots and protect properties that may remain at risk.
Containment does not mean that 25% of the fire has been extinguished. It means firefighters have established control lines around approximately one-quarter of its perimeter that they believe can prevent further spread.
The Lucas Fire began on Thursday, 10 September, near the boundary between Lake and Mendocino counties, southeast of Potter Valley. It expanded rapidly during its early stages as crews faced steep terrain, dry vegetation, strong winds and difficult access.
More favourable weather conditions later allowed firefighters to attack the blaze more directly. Night-flying helicopters were also deployed to slow its spread and support crews working on the ground.
The San Francisco Chronicle reported that five helicopters operating at night played an important role in helping crews turn a corner in the response.
Evacuation orders remain active
Evacuation orders and warnings continue to affect parts of Lake and Mendocino counties. Residents in affected areas have been advised to follow instructions from emergency officials and remain prepared for conditions to change.
An evacuation shelter has been established at Fritch Hall at the Lake County Fairgrounds, located at 401 Martin Street in Lakeport.
Separate arrangements are available for small animals, while people evacuating with livestock have been directed to use the livestock entrance on Estep Drive.
Temporary traffic controls have also been introduced along sections of Highway 20.
The US Forest Service has issued an emergency closure covering parts of the Upper Lake Ranger District in the Mendocino National Forest. The restrictions include affected roads, trails, campgrounds and off-highway vehicle routes.
Residents should consult official county emergency maps before travelling or attempting to return to an evacuated area. Evacuation boundaries can change quickly as firefighters assess weather conditions and activity along the fire’s perimeter.
Smoke may affect nearby communities
Smoke from the Lucas Fire could reduce air quality in Lake County and surrounding communities.
People with respiratory conditions, older adults, children and pregnant women may be particularly vulnerable to wildfire smoke. Local health authorities generally advise residents to remain indoors where possible, keep windows closed and reduce strenuous outdoor activity when smoke levels are high.
Drivers should also prepare for reduced visibility near the affected area.
Cause remains under investigation
The cause of the Lucas Fire remains under investigation. Officials have not announced any confirmed injuries or fatalities connected with the blaze.
Although containment has increased, authorities continue to describe the incident as an active wildfire. Fire behaviour can change with wind, temperature and humidity, particularly in steep areas that are difficult for ground crews to reach.
CAL FIRE updates incident figures regularly. Acreage, containment levels and evacuation information may therefore change after publication.
