Oregon ( ) is a state in the Pacific Northwest region of the United States. Oregon is bordered on the west by the Pacific Ocean, on the north by Washington, on the south by California, on the east by Idaho, and on the southeast by Nevada. The Columbia River delineates much of Oregon's northern boundary, and the Snake River delineates much of the eastern boundary. The parallel 42° north delineates the southern boundary with California and Nevada. It is one of only three states of the contiguous United States to have a coastline on the Pacific Ocean, and the proximity to the ocean heavily influences the state's mild winter climate, despite the latitude.