Pacific Northwest faces renewed flood threat due to atmospheric river

WASHINGTON - A storm system, paired with an atmospheric river, will move through the Pacific Northwest on Monday, causing more rainfall in an area that has been inundated with precipitation in recent weeks.

An atmospheric river is forecast to impact the area now through Tuesday. Widespread rainfall amounts between 1 and 2 inches are likely, with 3 to 5 inches of rain possible in areas such as the Olympics and Cascade foothills.

WHAT IS AN ATMOSPHERIC RIVER?

What causes an atmospheric river is a narrow corridor of concentrated water vapor — usually from tropical origins — that is being carried by the jet stream. They are Earth's largest rivers — but in the sky.

Several months of consistent precipitation has left Washington in need of a dry period, and Seattle is currently half an inch above its year-to-date average, leaving many regional rivers near flood stage.

In the past few weeks, one person has died due to dangerous flooding in Northern California.

WATCH: LEVEE FAILURE PROMPTS OVERNIGHT EVACUATIONS, IMPACTS HUNDREDS OF HOMES IN WASHINGTON

In Washington, two levees failed, resulting in a flood that left entire neighborhoods swamped, affecting over 220 homes in the city of Pacific. A man also drowned after he drove his car onto a flooded road, just south of Snohomish, Washington.

As warm air surges into the region, snow levels are expected to climb from 2,500 to over 7,000 feet by Sunday evening, creating hazardous conditions for mountain pass travel, according to the FOX Forecast Center.

HOW TO WATCH FOX WEATHER

The Skykomish, Snohomish and Skagit rivers are already near bankfull, which means more rain will likely trigger flooding by early next week.

Check back for updates on this developing story.