Unbelievably, frost heaves can pop up in the middle of winter, and can damage everything from roads and sidewalks to foundations and slabs. I used to live in Vermont and frost heaves were simply an unpleasant fact. Almost every January, we would have a mid-winter thaw that would melt and freeze the snow and ice. On years when the thaw was significant and there was a lot of snowfall, huge frost heaves would pop up.
My family actually had to repair the foundation of our barn because of frost heaves. A series of thaw and freeze cycles caused the ground to become saturated next to the bottom floor foundation wall. The saturated ground expanded when it froze, causing the wall to buckle and the foundation to crack near the edges.
The barn was over 100 years old, so it was likely from decades of freeze thaw cycles, but the repairs were very costly. If you tour almost any old farmhouse in the state, you will notice that none of them are plum square. Walls bow and wave, floors slant and tilt, and foundations eventually crumble. This happens regardless of how deep the foundation is poured because ground in that state is constantly moving.