Another atmospheric river will bring more rain to the Pacific Northwest later this week, heightening an extensive flood threat.

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.

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

As Western Washington reels from catastrophic flooding that swept the areas along major river valleys, another plume of moisture will arrive on Sunday.

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

WSDOT stated that crews have reopened more than 50 highways as western Washington is still recovering from an atmospheric river that caused historic flooding.

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.