Living in Laramie, and from my conversations, many times when I-80 is closed to all vehicles, not just high profile / light weight trucks, US-30 is also closed as to not overload a road that is only two lanes for about 3/4 of the distance from Laramie to Wolcott Jct. There are A LOT of trucks on this stretch as it is a better route to the west coast than 70, and if I-80 is closed due to wind or winter conditions, US 30 will get some, just not as bad. Combine the conditions on a two lane road with a lot of cross-country semis, and that road can be a parking lot as well with icy spots to boot.