Because of the low snow fall last winter and the early warm weather we had March. The great lakes are already 7c higher in temp than normal. Lake Ontario off Toronto is normally only 10c this time of year and it's already at 17c
This is because there was no major snow run off to keep the feeder streams and rivers cold which help keep the lakes cool.
So what this could mean for the coming winter is much higher snow amounts as the lakes will take much longer to cool off alown more lake effect snow.