I've actually had longer wait times around Niagara than I ever have when crossing at Sarnia - although it's completely hit or miss either way.

I certainly would not count on the snow having stopped by March 1st. March is actually one of the snowiest months of the year in the northern states (warmer temperatures actually mean more snow) and when you throw in the lake effect potential, especially south of lake erie, I'd say you have a relatively high chance of seeing snow. Of course, there's no way of knowing exactly what you'll see at this point, but I would certainly plan to see some snow at some point along the way.