Symbolism, Imagery, Allegory
It must be pretty windy in New England, because Adam is always commenting on it. The wind is a force of both good and bad in the book. It helps Adam keep momentum and spreads his singing voice through the air, but sometimes it "catches at [his] throat" (5.14) or "eats at [his] cheeks, biting chunks out of [his] flesh" (5.18). Sometimes it eerily bangs against motel doors (29.8).
What does the wind represent? We think it's the fact that sometimes the things you need the most – like wind to carry you along your journey, or a Mr. Grey to protect your family – can't always be trusted. As with the bike and the package, Adam associates himself with the wind. He says "I let myself join the wind" (1.16) and "I am with the wind" (3.37).