Originally Posted by
bikemig
If I were riding somewhere that had as much rain as Seattle, I'd think about a bit wider (and lower pressure) tire than a 700 x 28c. Anything that improves the tire's contact with the road is a plus I think in the rain. A 700 x 32c continental top contact would be a fine choice for all weather commuting.
My GP4000s are 700x25c and I have never had any wet traction issues.