Firefighters have reported progress against California’s largest wildfire of the year ahead of expected thunderstorms that could unleash fire-starting lightning and erratic winds and erode work over the past week to contain the blaze.
Containment of the Park Fire, now California’s fourth-largest wildfire on record, was at 27% as of Saturday afternoon, after relatively milder weather the last few days allowed firefighters to build containment lines.
CalFire official Mark Brunton said in a video update on Saturday: “We’re not completely out of the woods yet, but we’re looking very, very good. This is moving at a very fast pace.”
But hotter weather, fuels and terrain will continue posing challenges for the estimated 6,500 firefighters battling the fire, which has spread over 626 square miles since allegedly being started by arson in a park in the Sierra Nevada foothills east of the Sacramento Valley city of Chico.
For comparison, the city of Los Angeles covers about 503 square miles.
Suppression crews have started removing damaged infrastructure in some areas, and people living in the rural communities of Cohasset and Forest Ranch have been told they can return home.
The fire originated at low elevations, where it quickly burned through thick grass and oaks, destroying at least 567 structures and damaging 51 so far. As it has climbed higher, the vegetation has changed to a greater concentration of trees and brush, Cal Fire said.
The fire’s push north has brought it towards the rugged lava rock landscape surrounding Lassen Volcanic National Park, which has been closed because of the threat.
The area remains one of the biggest challenges for firefighters, Cal Fire officials said, and the smoke has prevented them from deploying helicopters and other aircraft the last few days.
After a brief respite, firefighters are now bracing for treacherous conditions of hot and dry weather, along with expected thunderstorms with potential lightning strikes and gusty winds.
The collapse of thunderstorm clouds can blow wind in any and all directions, said Jonathan Pangburn, a fire behaviour analyst with CalFire. “Even if there’s not lightning per se, it is very much a safety-watch-out environment for our firefighters out there,” he said.
The Park Fire is among almost 90 large fires burning across the western US. Evacuation orders are in effect for 22 of the fires, according to the National Interagency Fire Centre.
Crews made progress on Saturday against three major fires burning in Colorado near heavily populated areas north and south of Denver, with containment figures improving and some evacuation orders lifted. One of the fires is being investigated as arson.
About 50 structures had been damaged or destroyed, about half of them homes, and one person was found dead in a burned home earlier in the week.
The largest of the Colorado fires, west of Loveland, has grown to 14.9 square miles after previously burning 49 homes and other structures. Its cause is under investigation.
