While flooding may not reach the historic levels seen last week, a KIRO 7 meteorologist said the overall impacts could actually be worse.

The weather service has issued a flood watch for northwest Oregon and southwest Washington from early Thursday to early Saturday.

(THE CONVERSATION) Along the U.S. West Coast, atmospheric rivers are dreaded for the damage they can cause, but they are also essential to the region’s snowpack and water supply, as Qian Cao, a hydrologist at the University of California, San Diego, explains.

What is it about mid-December weather? The latest atmospheric river has brought warm, heavy rain, resulting in widespread major flooding and landslides.

As another atmospheric river moves over Washington, it is expected that the area will receive another 5-8 inches of rain. This comes just days after a historic flooding devastated parts of Washington.

Starting tonight, an atmospheric river takes aim at northwest Oregon. Heavy rain and strong winds are back in the forecast.

Cowlitz River below Mayfield Dam also remains under flood warnings on Tuesday, “until further notice,” as the river flow has risen above 25,000 cfs—the flood stage threshold. Flooding is expected from Mayfield Dam downstream through Toledo, covering farmlands and roads, mainly near Toledo, as flows stay near 29,000 cfs through Wednesday.

Powerful wind gusts knocked out power to more than 500,000 customers across Washington and Oregon early Wednesday, as the latest atmospheric river intensified over the flood-devastated region. The Skagit River forecast indicates it will rise back into major flood stage early Wednesday.