Unless you just plan on skipping races because it’s raining (noooo!), you should never skip a training session just because it’s raining.
We’ve seen athletes use this approach to mentally crush their competitors time and time again — a little rain? A little wind? No problem — you’ve trained in it, and you know how to handle it. Let your competitors spend their energy on race day worrying about the wind and rain — that stuff will be routine to you, and you’ll spend your energy on crushing your competition.
Thunder and lightning and other unsafe conditions are a different story, of course. But rain? Wind? You got this.
