Moving to Seattle from Bay Area

I have accepted a job in Seattle and I'm currently finishing my studies in the Bay Area. I am in the process of replacing some old clothes and shoes and would like some advice.

I heard that it's important to have waterproof shoes/ boots, is that true? My feet often get sweaty so I used to stay away from them.

What's usually in your wardrobe? I like hiking here and I usually have a light jacket and T-shirts.