zucchini developing large bumps

Question

My zucchini are fine when I pick them but after sitting on the counter for a few days, they are developing large bumps. When you cut them open, they look fine. The skin also is perfectly smooth, just the large bump that forms that looks like a tumor I guess. Any idea what’s going on?

Answer 1

https://www.gardeningknowhow.com/edible/vegetables/squash/yellow-bumpy-squash.htm