In the Redding area, where the Carr Fire has killed six people, including two firefighters, winds of 25 miles per hour, temperatures above 95 degrees Fahrenheit, and extremely low humidity are in the forecast from Thursday evening until Saturday, the National Weather Service said.
This could lead to “dangerous and rapid irregular spreading of a large wildfire,” the service said in an advisory.
The Carr Fire has destroyed more than 1,550 structures in and around Redding, a city of 90,000 people about 160 miles (260 km) north of the state capital, Sacramento.
Authorities have reopened more evacuated neighborhoods as ground crews, aided by diminished winds, extended buffer lines carved out of thick, dry brush along the fire’s edge to 35 percent of its perimeter, officials said.
California Department of Forestry and Fire Protection (CalFire) commanders said on Wednesday the fire, sparked by a vehicle on July 23, was burning with less intensity this week and posed little immediate threat to populated areas.
Overnight, crews faced wind, steep terrain, and dry fuels, CalFire said in a report on Thursday morning. “Throughout the day crews will continue to mitigate spot fire potential across control lines,” it said.
Despite the outlook, strong gusts along the upper ridge lines were a concern on the fire’s rugged western flanks, a few miles from the town of Lewiston, which remained evacuated.
More than 4,200 firefighters are battling the blaze, which has scorched more than 125,800 acres in the scenic Shasta-Trinity region.
Law enforcement officials said the last four people reported as missing were found safe on Wednesday.
The Carr Fire was one of eight large wildfires burning in the state and 93 burning in the United States, mostly in the West, according to the National Interagency Fire Center.
The wildfires have been fueled by years of drought-dessicated vegetation, and stoked by frequent bouts of erratic winds and triple-digit temperatures.
To the southwest of the Carr Fire, more than 3,000 firefighters were battling the 95,000-acre (38,450-hectare) Medocino Complex, made up of the Ranch and River fires that have destroyed seven homes and forced thousands to evacuate. High temperatures, low humidity, and afternoon winds along with low fuel moistures are aiding large fire growth, officials said.
Reporting by Brendan O’Brien