This argument for when summer should occur isn't as strong as the previous two, and certainly only applies to parts of the coastline, but I think you can make a reasonable argument to why it might apply.

I know lots of people think of summer as the time when you can go to the beach and enjoy swimming in the warm waters of the Atlantic Ocean or Chesapeake Bay. So, I think you could also reasonably expect that summer might be based on the 90 days when the water is the warmest.

You might think that water temperatures would be very similar to when our air temperatures are the warmest but they aren't. That's because water heats up and cools down more slowly than land (or most solids). If you don't believe me try this experiment. Heat a loaf of bread in an oven to 212 degrees then bring it out and let it sit for 5 minutes. Now, stick your hand in it. It will be warm but sure won't burn you. Try doing that with a pot of water which is also 212 degrees when you pull it off the stove and you will get a serious burn (so, DON'T try this at home).

Because of the difference in the heating rates, our ocean and bay temperatures are actually warmest during the period of July, August, and September.

Tomorrow, part IV.