Ok I'm not sure what is going on and need some input. had pool up for about two weeks now. First week rained a lot, now this week sun is out for 4 days in a row , with solar blanket on yesterday temp went up to 82 at 4:30pm then I went in at 7:30pm and it felt really cold looked at temp an it read 75! wth! what is going on? it didn't drop that fast last yr ever! we got out put cover back on and this morning it is 72. Not a happy camper with temps like this and its been in the 80s all week here during the day. is this normal?