Hello everyone, my girlfriend and I are leaving on a month long roadtrip in 10 days with no constraints except ourselves. The theme of the trip is national parks as we will hit between 10 to 15 encompassing the whole country top to bottom and back and forth. With much research I realize the northern parks (Mt. Rainier, Northern Cascades, Glacier) will not be 100% open. Is it worth it to travel to these parks only to be denied many of the roads within the parks? We will be traveling in a Chevy s-10 with 4-wheel drive. Should I purchase chains? Thanx for the help.