Squash Rot

Hello everyone,
My father in law lives in Coronado and is growing yellow squash and is having a problem with them rotting (see photo). It gets full sun (for the coast), regular water. Any suggestions?

thanks for any suggestions!

I do not have a solution but I can tell that the same thing happens to my yellow squash also this year. Usually squash is one of the most reliable producer in my vegetable garden.
I hope that someone could explain the reason for the rot.

We have had an unusually heavy Marine Layer this summer, lots of moisture in the air. Try thinnig out your squash to allow better air circulation.