We had a bit of heat wave the last few days (along with some bad fires in the hills above us), so we gained a bit more heat and were back up to 83° water temp yesterday.
Last week we were in the 79-80° range.
With the lower sun angle, which adds some more shading from our house and surrounding trees, we are not getting much heat gain at all anymore. In the summer months, June-August, I could open the pool when the sun was shinning and get quite a bit of noticeable heat gain - now though we don't get any heat gain at all when we have the auto cover open. One day last weekend it was 80° at 10am and 90°+ out most of the day, but the pool sat at 81° all day with the cover open.