Portland, OR – A potent atmospheric river is set to drench the Pacific Northwest beginning late Sunday night, with heavy rainfall expected to persist through much of next week. The National Weather Service (NWS) has issued a Flood Watch for much of western Oregon and Washington, including the Portland metro area, the Willamette Valley, and Seattle-Tacoma regions.
According to the NOAA Weather Prediction Center, the system could deliver 6 to 12 inches of rain to coastal and mountainous areas, with 4 to 6 inches likely for inland valleys. The heaviest rainfall is forecast from Monday through Wednesday, with lighter showers continuing into Friday.
The NWS warns that urban, small stream, and river flooding are all possible. Coastal rivers and tributaries draining the Coast Range and Cascades have the highest flood risk, while landslides and debris flows may occur in steep or recently burned terrain.
“Excessive runoff may result in flooding of rivers, creeks, streams, and flood-prone areas,” the agency said. “People near steep slopes, canyons, or burn scars should be alert for rapidly moving landslides.”
Residents are urged to stay weather-aware, have multiple ways to receive alerts, and never attempt to drive through flooded roads.
Flood Watches remain in effect through Thursday night for Oregon and Friday afternoon for Washington, covering areas from the Oregon Coast and Willamette Valley to the Puget Sound region.
