UPDATE 10:20 a.m.--As of 10:20 a.m., Interstate 80 was closed in southwest Wyoming between Evanston and exit 39 near Lyman. It was unclear when that stretch of highway might reopen.

As winter weather enters the Cowboy State, the chain law (level 1) has been activated for a portion of Interstate 80, according to the Wyoming Department Of Transportation website.

You can read about Wyoming's chain law, including the different levels, here. You can access the WYDOT road and travel report here.

Winter weather is expected across much of Wyoming today and tonight, and the Cheyenne office of the National Weather Service says many areas of southeast Wyoming may experience slick roads and less than ideal travel conditions Wednesday night and early Thursday.