Residents of western Washington state are packing up valuables and preparing to flee as heavy rain causes rivers to rise.

An atmospheric river is swelling rivers toward record levels, with major flooding expected in areas like the Skagit River, north of Seattle.

On Wednesday, dozens of vehicles were backed up at a sandbag-filling station in the town of Mount Vernon.

Authorities warned residents within the river's floodplain to be ready to evacuate.

Washington Gov. Bob Ferguson has declared a statewide emergency.

The weather service expects several days of heavy rainfall along the coast.