>>2840385Because of the layout of the North American continent.
Thunder storms happen when there is warm air at the surface under cool air above and they meet. They're most common where it is hot and humid, over larger landmasses.
The areas over the South Eastern US create these conditions more than other areas. Thunder storms are most common in tropical regions.
They're more common in France than in England, and more common in the South East of England than in Scotland, where they're relatively rare.
