Crews work on Park Fire containment, extinguish hot spots in Northern California wildfire

Firefighters on Wednesday continued putting out smoldering spots along containment lines of the Park Fire, keeping flames within the footprint of the Northern California wildfire.

For a second day, the size of the Park Fire remained at 429,259 acres (670 square miles) as of Wednesday morning with containment increasing from 39% to 40% over 24 hours, according to Cal Fire. Most of the fire activity remained in the northeast portion of the fire in Tehama County.

There was minimal fire activity overnight, according to a Cal Fire Wednesday morning situation summary. Firefighters were working on mop-up operations and patrolling areas along containment lines to ensure communities are safe for residents to return to their homes.

The area continued to experience favorable weather conditions, and Wednesday was expected to have slightly less potential for spot fires and less heat along containment lines, said Jan Smoots, a fire behavior analyst for Cal Fire .

Cal Fire anticipated a slight increase in wind speed over the region to the north of the Park Fire, with gusts reaching 17-22 mph over exposed ridges. But calmer conditions were expected to return to the area in the evening.

“We might have some potential for reburn in areas where we’ve got continuous fuels lined up adversely to your (containment) line. Pay attention to that,” Smoots told firefighters in a Wednesday morning operations briefing. “We still got a lot of dead standing trees that are burning up at the tops and may have potential for ember production that could blow across lines.”

Cal Fire expected to see seasonably warm and dry afternoons this week followed by nights with moderate to good humidity levels to help suppress any potential fire activity.

Spot fires occur when floating embers drift in the air land on the unburned side of a fire containment line. Conducting mop-up involves removing or extinguishing all burning or smoldering material along containment lines.

More 5,400 firefighting personnel on Wednesday were assigned to the Park Fire. Cal Fire said firefighters are working to mitigate smoke, suppress spot fires, remove hazardous trees weakened by flames and strengthen containment lines and contingency containment lines to prevent any potential flare-ups.

The Park Fire on Wednesday remained the fourth-largest wildfire in California recorded history . The third largest was the Mendocino Complex Fire that started in July 2018 and burned 459,123 acres. The August Complex Fire that burned 1.03 million acres in seven Northern California counties is the largest in state history; it killed one person and destroyed 935 structures.

The wildfire has burned more than 376,000 acres in Tehama County and nearly 53,000 acres in Butte County. The wildfire also has affected areas in Plumas and Shasta counties, where some evacuation warnings remained in placed Tuesday, according to Cal Fire.

The Tehama County Sheriff’s Office on Tuesday afternoon announced that evacuation zones in the foothills along the west flank of the Park Fire footprint were returned to “normal” status. Evacuation orders were reduced to evacuation warnings in zones in the community of Mineral.

The Park Fire, burning into its 21st day on Wednesday, started July 24 in Butte County just east of Chico after a suspected act of arson.

The Park Fire is C alifornia’s largest wildfire caused by arson in recorded history. The wildfire has destroyed 641 structures and damaged 52 others in Butte and Tehama counties, according to Cal Fire. The total includes infrastructure.

In Butte County, the fire destroyed 428 structures and damaged 47 others. Cal Fire said the fire destroyed 213 structures in Tehama County, damaging five others.