PLENTY OF SNOW greets motorist on top of Thompson Pass. While the pass officially opened on Monday, vehicles could get through to Idaho over the weekend. Jon Sonju of Thompson Falls traditionally attempts to be the first person over Thompson Pass. Though he didn't get that title this year, he did report that he went over twice last weekend. Several feet of snow remain on top of the pass, and Montana Department of Transportation staff said that it took more than six hours to clear the parking lot.