Fall is the peak time for wave height, partially because the lake is at its warmest after soaking up the sun all summer. When the colder air within a storm system moves down the 200 to 300 miles of the lake from north to south, the difference in temperatures can cause extra strong winds to develop.
Showcasing Chicago One Image at a Time 
Never having been to one of the great lakes, I find it very impressive that a lake’s waves can crash so big. Amazing.