The spread of a major wildfire in the Siskiyou Mountains along the Oregon-California border has slowed with cooling temperatures, giving firefighters a chance to build containment lines. But more lightning is predicted, and it could start more fires.

The Northwest Interagency Coordination Center in Portland reports the Oregon Gulch fire 15 miles east of Ashland was 20 percent contained on Monday at 72 square miles -- 57 of them in Oregon in Jackson and Klamath counties.

Spokesman Tom Knappenberger says after two straight days of major runs, the fire burned only about 7 square miles on Sunday.

Thunderstorms are expected Monday night and Tuesday morning, followed by calmer weather until the weekend.

The Oregon Gulch fire burned six scattered rural homes last week and still threatens 270 more.