The weather in the Pacific Northwest is dependent on the Pacific Ocean. Generally speaking, weather in the region is mild, with cool wet winters, and warm dry summers with extremes in temperature and precipitation being unusual.

The Central Pacific Northwest Coastal Forests region is a thin but long region extending from the southern Oregon coast in the south, northward through coastal Washington

The 3 major ranges of the Northwest US Coast Ranges - the Klamath Mountains, the Oregon Coast Range, and the Olympic Mountains - all have their own unique geological history.