The three thumb rating doesn't apply to the foolhardy or to unaccompanied or uncontrolled children. Be warned. Th Strid is potentially lethal.
Once you remember that and keep well back, it's a terrific sight, the worse the weather, the more impressive it is. The water of the river Wharfe is forced into an absurdly narrow channel where it bubbles, froths and rushes, hiding underwater caves.