Ralestone Luck by Andre Norton — Read

The rain, fine and needle-like, stung Val's face. There were ominous pools of water gathering in the garden depressions. Even the small stream which bisected their land had grown from a shallow trickle into a thick, mud-streaked roll crowned with foam.

But the bayou was the worst. It had put off its everyday sleepiness with a roar. A chicken coop wallowed by as the boy struggled with the knot of the painter which held the outboard. And after the coop traveled a dead tree, its topmost branches bringing up against the plantation landing with a crack. Val waited for it to whirl on before he got on board his craft.