This was the first chase day for me personally. One day earlier some really nice looking storms effected the extreme portions of Southwestern Ontario but they arrived late and were a little too far for me.
Today, the storms were all popping along a warm front that was pushing north.
The main body of the convergence started in Michigan just southwest of Sarnia and spread north to Peterborough, Ontario.
Initially the front was making good progress but began to increasingly slow as it encountered the cold waters of the Great Lakes and open ground with increasing snow cover.
As convective waves moved through and laid down outflow boundaries this pushed south, against the mean flow and in essence the surface warm front began to retrograde with convective activity becoming increasingly more south as time went on.