We were there at the end of March. The pools themselves were heated. But the slides are not and they were quite cold. The ones at the Oasis pool (2 that go directly into the pool) were not bad and my kids did fine one those. The ones at the Lagoon pool, however, were very cold. They are in a separate structure right next to the pool and the slides do not go into the pool itself. Although these are the best slides, my kids didn't last too long on them because they were so cold. I put one foot in (with the intent to go on) and said, No way! So we stayed in the pools most of the time - they were heated nicely.