Dan, 
It's surprising the lower two rows of modules did not heat up sufficiently to
melt completely clear once most of the snow had been removed. In my experience
any remaining layer of ice starts melting immediately once the sun reaches the
cells and they begin to warm up when they start producing power.  
Dick Ratico

You wrote,
We did set it up so the bottom two rows were on their own CC and could be
cleared from the ground, but they never did totally clear.

