Base layers are for moisture management. A next-to-skin layer, they work by wicking moisture away from your skin and can also help to prevent chafing. These are the base layers I’ve used and recommend.
Outer layers are for rain, wind and snow protection. A waterproof rain jacket is a must for hiking in the Pacific Northwest – add rain pants when the forecast calls for wet or cold weather. There are my favorite rain gear items that I’ve used and recommend.