Some rivers may break records. Already, overnight into Tuesday, the Naselle River near Naselle, Washington, has gone from its normal 5 foot depth to nearly 20 feet deep, growing by 10 feet in 12 hours and coming within less than 1 foot of the historical record.

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

Record river flooding is ongoing in parts of Washington State, but following a drier weekend, a new worry for wetter weather will arise early in the week ahead.

The National Water Center said that "considerable" flooding impacts are expected across the Cascade Foothills to Puget Sound, with urban and minor river flooding also possible throughout the remainder of western Washington and parts of northern Oregon. It also warned that landslides would be possible along the Cascade Foothills.

Western Washington residents woke up Monday to their final hours of dry weather before a powerful atmospheric river unleashes 10-15 inches of rain.

Oregon is in for several days of heavy rain, strong winds and rising rivers as two atmospheric river surges push across the state through midweek.

The Skagit River is predicted to crest at more than 47 feet near the town of Concrete, north of Seattle, 15 inches above the threshold for a major flooding event.

November was a somewhat dry month for Portland at just 4.67 inches. During an average November, the airport gets about 5.55 inches of rain. For comparison, during an average December, the airport gets about 5.77 inches of precipitation. Atmospheric river shifts northward. Wednesday brings Portland lighter rain, gusty winds Dec. 10, 2025, 5:42 a.m.

The wording and definition were changed and refined a bit as atmospheric scientists at MIT studied these storms in the 1970s.

We have a very active weather pattern that will impact the region this week as an atmospheric river takes aim at the Pacific Northwest.

A storm system Tuesday into Wednesday will bring stronger winds, heavy mountain snow, and the threat of downed trees and power outages.