Not from up there, but we have lots of Canadian friends in the park in Yuma. Just about all use I-15. Just watch the weather for Monida Pass (Idaho/MT. state line). Idaho Dept of Trans has web cams set-up at that location. Between there and Dillon, MT. seems to be their biggest worry, but of course I will ad a disclaimer, it could get nasty anywhere above St.George, UT. But our friends in Calgary, Edmonton, Lethbridge, and Sask. use this way. I'm sure there will be more replies offering ideas. By all means have a safe trip and have a good time!