All I know is that 11,000 volts through a yacht mast hurts lots! Personal experience, probably explains why I am so stupid!
That discharge travelled some distance from the lines to the top of the mast. I don't know the distance but it would be worth checking with the power authorities before your road trip!
I am told that lightning picks out taller objects, but 12 cows were killed over here last week standing under trees so there goes that theory. Earth strap to the ground??? Gee I don't know, just the ramblings of another lost soul!