Forth,
You have a lot of very good advice here, there is one that has been overlooked. One that has worked well for us forever.
If you can, plan an extra day in the schedule.
When traveling in an RV in the time of year for winter storms, always have previsions and fuel (all) for three days of sitting still. When it gets bad, it can easily take a whole and complete day to get back to safe conditions. Find a safe place to hunker down. Turn the heat on and watch the mayhem go by. This is why we travel in our own coach.
Why Three Days?? Because it is pretty sure to take the day for the roads to be worth trying, so there are two days. They third day is just for reserve. We have not yet needed all three, but one never knows.
I had worked this way for a while, but once we (I, DW, DS and DD) were on our way back to Michigan when the weather closed in. We got of the highway just west of the Delaware Water Gap and we got the last hotel room and the last Pizza to be had. The lesson was confirmed.
Matt
I forgot to add, that in decades of automotive testing, I have never seen a reliable black ice detector. I do remember testing three and then getting repairs to two test vehicles. The third only needed a new wheel.
Again.