While the temperatures in the Arctic are still very cold, they have warmed almost twice as much as the rest of the Earth due to climate change. In order to understand what is going on, an analogy that may help is to think of a giant mound of cold air centered on the North Pole. The colder the air, the taller and steeper the mound. As the Arctic has warmed, the mound has flattened somewhat.
Now think of the jet stream (which shows up on most weather reports) as a closed loop river circling around the Earth, centered at the North Pole.