PORTLAND, Ore. (KOIN) – A weak and considerably short-lived atmospheric river will hit the greater Portland-Vancouver metro area this weekend. Soaking rains that moved into western Oregon and Washington on Friday will continue to intensify through the weekend. Rain accumulation will continue to add up from the coast to the Willamette Valley until the middle of next week. A late-season Winter Weather Advisory is in effect for the Cascades as snow returns to the mountains.