It really depends were your from, and how cold of water you can stand to swim in. We have friends who come and visit us in November from Indiana. At that time of year it's common to have a cold front bring the temps. down to about 50 degrees, and be back up in the 80's a few days later. They always swim in the pool, and the gulf, sometimes my kids will join them, but it's too cold for me. October is nicer, cooler at night, comfortable during the day, some days in october I may swim.