SEATTLE -- With a forecast of up to three feet of snow in the mountains, it convinced the Department of Transportation to close the North Cascades Highway for the weekend.

State Route 20 will close Thursday at midnight, from just east of the Diablo Dam to just West of Mazama.

Officials say the big danger is avalanches or snow slides.

The DOT will evaluate conditions Monday and decide whether to reopen the highway or close it for the winter.

Chinook and Cayuse Passes are also shut down so the DOT has time to make sure everybody is out of the area before this weekend's expected snow.

The DOT will decide on Monday whether the roadways should stay closed until spring.