Metaphors are comparisons that do not use the words like or as. Shelley's "Ode to West Wind" is dense with metaphors. A few are described below.
Shelley speaks directly to the West Wind in this poem, using the archaic pronoun "thou," the intimate form of "you" that implies friendship. He is thus implying the West Wind is his close friend.
In the first stanza, he uses a metaphor when he states the West Wind is the "breath of Autumn's being." He is likening the way it blows to the way air or breath emits from the body of a human being or a living creature. (He is also employing a metaphor in comparing autumn to a living creature, a "being.")
Shelley uses a metaphor when he likens autumn's leaves in their various fall colors of "yellow, and black, and pale, and hectic red" to "pestilence-stricken multitudes." In other words, the dead leaves look to him like human beings who have died of a plague or epidemic.
He compares the West Wind to a chariot driver:
Who chariotest to their dark wintry bed.
He also uses a fanciful metaphor when he likens the leaves to "winged seeds."
2, Shelley likens the ocean and the heavens (the sky) to the limbs of a tree, "the tangled boughs of Heaven and Ocean."
He compares the way clouds mass in the sky to hair on a person's head, calling them "the locks of the approaching storm."
Shelly uses a metaphor when he compares the sound of the wind to a funeral song, calling it the "dirge / Of the dying year."
In canto 4, he likens time to a chain:
A heavy weight of hours has chain'd and bow'd
One too like thee: tameless, and swift and proud.
Finally, in canto 5, Shelley calls to the wind, asking, "Make me thy lyre," comparing himself to a harp-like instrument he hopes the wind can play.