My opinion is that it would be entirely dependent upon how your son reacts to the water. Unless he has an aversion to it in general I've never found the water to be too cold. And there is always the hot tub, lazy river and toddler wading area if that were how he felt upon getting there. I love this place and wouod suggest it is worth the risk.
Just take a sweatshirt, kids run hotter than adults, so should be good . The wind will keep the bees away.
They are a seasonal location so if they are open i would say its fine.
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