SEATTLE (AP) — Winter weather advisories were issued for western Washington and Oregon as overnight snow snarled roadways and prompted school closures.

Forecasts were for up to 4 inches of snow in Seattle and even more was predicted in other areas of the Puget Sound. Many schools were closed Monday and others posted delayed starts.

The Cascade Mountains could see 30 inches of snow through Monday afternoon as the snow level was expected to fall below 1,000 feet. People were advised to only travel over Snoqualmie and White passes in an emergency.

Crashes closed Interstate 90 eastbound near Snoqualmie Pass for about two hours early Sunday.

Snow and treacherous conditions were also possible for the greater Portland, Oregon, area.