Snowy view of Northeast, Midwest as atmospheric river collides with bomb cyclone in Pacific Northwest

A bomb cyclone that slammed into the Pacific Northwest with hurricane-force winds, knocked out power and left at least two people dead, converged with “an atmospheric river” of moisture expected to bring heavy rain and snow to much of the same region .

The National Weather Service said an additional six to 12 inches of precipitation was forecast for parts of Northern California through Friday, while heavy snow was possible from the Washington Cascades to western Montana, Idaho and northwestern Wyoming through early Sunday.

The excessive rain and snow comes on the heels of a bomb cyclone that hit Washington state, where wind gusts of up to 77 mph were recorded.

According to PowerOutage.usmore than 300,000 customers were without power in Washington state early Thursday.

ABC News reported that a woman was killed when a tree fell into a home in Bellevue, Washington, while she was in the shower. Another woman was killed in Lynnwood, Wash., when a tree fell on a homeless camp, officials there said.

The “atmospheric river” event was one of two major storm systems affecting much of the United States as millions of Americans prepare to travel next week for the Thanksgiving holiday.

• Read more from Yahoo Life: How to stay safe and warm in winter weather: expert tips for your home, your car and your family

Close to blizzard on the plains

According to the National Weather Service, another system — which brought severe thunderstorms to the central and southern Plains and sparked a tornado in Oklahoma earlier this week — collided with arctic air, causing widespread snow to develop over the Dakotas, Minnesota and Wisconsin.

Heavy snow and gusty winds that created near-blizzard conditions across the northern plains on Wednesday could do so again in the upper Midwest on Thursday.

Snow from the mid-Atlantic to the Northeast

Separately, an upper-level low-pressure system was forecast to develop over the Great Lakes on Thursday, bringing cooler temperatures, cold rain from the Ohio Valley to the East Coast and accumulating snow for the central Appalachians, the weather service said.

Winter weather warnings have been issued from the mid-Atlantic to the Northeast, with up to a foot of snow possible Thursday and Friday, especially in the higher elevations of West Virginia and Maryland, the weather service said.

While most people in the Northeast and New England will see rain, at least six inches of snow is expected to fall across parts of northeastern Pennsylvania and New York’s Catskill Mountains by the end of the week.

How about Thanksgiving?

Forecasters have yet to issue forecasts beyond seven days, but if any of the impacts persist, the severe weather outbreak has a chance to snarl holiday travel.

Nearly 80 million people are expected to travel more than 50 miles for Thanksgiving next week, according to AAAwith Tuesday and Wednesday expected to be the busiest times on the roads.

• Read more from Fox Weather: Thanksgiving travel could break records this year, but extreme weather could snarl pre-holiday traffic