How tall do you think my colt will get?

Currently he is 1 year and 1 month old, he is 13.3 hh and is a leopard appy. His mother is about 15hh and his father is just a little over 15hh. This is our mare's second foal incase that matters. He currently gets 6lbs of alfalfa, 1 lb of timothy hay and 1 cup of empower in the morning and the same at night.How tall do you expect him to get?