I've never realised that the North-West Wales coast was so vulnerable, but that's because I've never been there!
In my youth we used to ride, in February
to Conwy for the Dragon Motorcycle Rally. Heavy rain, or snowmelt, tended to turn the rivers and waterfalls into something magical, but made route planning nearly impossible
I have to admit that I've never been to that part of Wales in the Summer, but reckon if it's good to look at in Feb it must be stunning in summer.