Swimming weather usually lasts through September in our area, and often into October. There is usually no real risk of freezing until after Thanksgiving, so there is no reason to hurry up and close your pool. The biggest factors in determining when to close your pool is how many trees you have and which type of cover you have. The rule of thumb is to leave the system running until the water temperature drops below 60 degrees to minimize algae growth. If you have many trees in your yard, once the leaves start falling, you may find that you may have to clean out your skimmer baskets and your automatic cleaner bag as much as 2-3 times a day. If you cannot keep up with this, you may want to close earlier rather than later.
If you have a mesh cover, remember to “close late and open early” to minimize the algae growth that can occur because sunlight passes through the mesh. Some folks that have a mesh cover will put the cover on as soon as the leaves start falling but will leave the pool operating underneath.
If you have a solid cover, you can close earlier. Some folks with solid covers wait until most of the leaves have fallen before they close. Regardless of what type of cover you have, the less time your pool is dormant, the fewer problems you will have during the rest of the year.