"Wind" is a poem about a wind that breaks things and not the other way around (breaking wind). This is a subtle distinction, often missed by many.
Ted Hughes makes his point clear: this isn't a pleasant balm, a cheerful, easy-going breeze. This wind means business—nasty business in the reprehensible spirit of Limp Bizkit's "Break Stuff." Just look at what it's doing and how it's being portrayed, as though it were a living thing, a beast, itself:
The woods crashing through darkness, the booming hills,
Winds stampeding the fields under the window
Floundering black astride and blinding wet (2-4)
Here the wind becomes a synecdoche for Nature itself—a part standing for the whole. Like Nature, the wind doesn't give a hoot for humanity or anything else. It's majestically indifferent and violent. It has its own work to do, and the work isn't pouring you a nice cup of tea and making sure you're comfy. It's knocking magpies out of the air, snapping branches, and making stones scream. This is the wind as Dwayne "The Rock" Johnson—destructive, uncontrollable. It cannot be tamed.
The speaker gets a face-full of wind, which learns him right:
Once I looked up—
Through the brunt wind that dented the balls of my eyes
The tent of the hills drummed and strained its guyrope,
The fields quivering, the skyline a grimace,
At any second to bang and vanish with a flap; (10-14)
The wind feels like it could annihilate the entire world, snapping it up like an old piece of canvas. Everything feels like a piece of flimsy cardboard, when faced with its awesome power. Hughes uses the wind to make us confront forces in Nature that are greater than ourselves—and to attain a kind of humility and reverent fear in the process.