Officials said that fire crews made significant progress against the wildfire that had been burning for almost a week in Southern California’s coastal mountains.

Over 1,600 firefighters battled the blaze in Santa Ynez Mountains west Santa Barbara by air and land. Federal officials reported that they were able stop the fire’s forward growth and that 78% of it was contained.

The Alisal Fire, which began last Monday, has burned nearly 27 miles (69 kilometers) of land. It threatens approximately 400 structures.

Firefighters quickly put out a spot fire measuring 1 1/2 acres (0.6 hectare). It was ignited by a retardant line at the northwestern corner. Fire crews focused their efforts on increasing containment, as there were few hot spots left.

Officials said that Sunday’s cooler temperatures were expected, but that winds of around 20 mph (32 km/h) were still possible in the region.

Last week, the fire spread quickly down the mountain range and jumped a railroad and highway to reach the beach below. Since then, the firefighting weather has improved greatly and it is now possible to use helicopters and airplanes to bombard the fire using retardant and water.

According to the California Department of Forestry and Fire Protection, wildfires in California have destroyed nearly 3,900 homes and businesses, and scorched close to 3,900 square miles (10.101 kilometers) of land.

Wildfires are becoming more difficult to combat because of a historic drought in the American West, which is linked to climate change. It has already killed millions of trees in California. Scientists believe that climate change has made West more dry and warmer over the past 30 years. This will make wildfires more destructive and more frequent in the West.