That’s making me want to buy a solar heating system for the pool. My pool builder said they were a waste of money, but your numbers would suggest otehrwise. Our pool was nice yesterday, but was only 77. Out of curiosity, is your pool dark? Mine is light and it seems the dark pools are warmer. Not sorry I went with the light bottom, I love the way the pool looks.

We have the French gray plaster (white) and will use a bubble wrap type cover at the start of spring and fall to supplement the solar. Variable speed pump. Like you we are in SB and it seems like those breezy days pull the warmth out.
localguy