Replying to Mt. Bachelor and snowtires

Don't know if i'm going to get any answers but it's worth a shot. I'm thinking about getting a season pass to Mt. Bachelor in Oregon this year and I live on the other side of the cascades (Corvallis to be exact) and was wondering to any Bachelor goers what is there to expect going over the cascade in terms of snow and weather (going through HWY 20)? Also another question, I have a 4x4 ford explorer with all weather tires but not winter tires and was wondering if i'd be fine without studded or actual snow tires. Just wanted to get some of your guy's opinions.