A piece of the polar vortex spills into the Midwest, creating extreme cold for the Chicago area and northwest Indiana for the next few days. For Sunday morning, actual air temperatures will peak early and fall throughout the day.

As Arctic air blankets the eastern United States, the National Oceanic and Atmospheric Administration has released its latest weather outlook for the last week of January -- but will Portland see those frigid temps or snow?

According to the National Weather Service, a polar vortex will impact most of the country this weekend, here is what you need to know.

Some areas of the U.S. may see temperatures as low as -20 or -30 degrees early next week as arctic air from Siberia rolls in.

A huge swath of the U.S. was blasted with ice, snow and wind on Monday as the polar vortex that dipped south over the weekend kept much of the country east of the Rockies in its frigid grip,