I'd have to agree with Bill and Ray on this one. If you even think you need chains on the trailer, stay below the snow zone and drive into it from there...
Safety First!
That's what I'm going to do over the long Thanksgiving weekend. We're going to head for Mt Hood in Oregon's Cascade mountains. (Only an hours drive from home here in Portland...) We'll camp in Welches at the 1200 foot level, with little or no snow, and then drive up and play!
Using the TM for this sure beats commuting or paying hotel and dining fee's!!!
Gregg