This graph is a bit surprising to me because when i first looked at it I thought that he north would be less predictable while the south would be more predictable. I always heard stories of Texas having lots of weather stories but i had no idea it compared to Michigan. This graph in my experience is very accurate to the places I've visited, Must be after gathering data for 20 years just to put this together. Now all they have to do is tell us which state is the nicest year round usually.