Firefighters are making progress in containing several of nine major wildfires in Colorado, though a mix of hot weather and rains in the south and southwest are bringing fresh challenges.

Fire crews have contained 50 percent of a southwestern Colorado fire that has blackened 85 square miles north of Durango. Authorities said Saturday that afternoon storms could produce flash floods and mudslides in burn scars.

In southern Colorado’s Costilla and Huerfano counties, firefighters have encircled about 55 percent of a 167-square-mile fire that destroyed more than 130 homes. A key section of U.S. 160 near La Veta opened Saturday afternoon, was shut down again briefly because of fire activity near the road, then reopened again in the afternoon.

Firefighters from 20 states are battling an 8-square-mile wildfire in central Colorado’s Roaring Fork Valley. Commanders hope for one-third containment late Sunday.

In central Colorado’s Park County, crews have encircled one-third of a spotty 20-square-mile fire that forced the Buffalo Creek Wilderness to close. A 15-mile stretch of busy U.S. 285 between Fairplay and Antero Junction reopened Saturday.

A Colorado-based Boeing 747-400 supertanker has been deployed to California to help fight wildfires that have destroyed dozens of buildings and caused at least one death.

Scott McLean, deputy chief of California’s Department of Forestry and Fire Protection, said Saturday that the supertanker is undergoing final checks at McClellan Air Base outside Sacramento. Once cleared by the state and the U.S. Forest Service, the plane can be sent to fires anywhere in California.

McLean and the aircraft’s owner, Global SuperTanker Services of Colorado Springs, say software issues must be resolved before the plane is activated under a call-when-needed contract. The aircraft can carry 19,200 gallons of water, retardant or suppressant.

Global SuperTanker CEO Jim Wheeler said in a statement that the company also has been negotiating with Colorado, which like many Western states is battling several large wildfires.

The plane first flew missions last year in California.