up north
To, in, or at the northern part of a country or the world. People from both sides of the political spectrum always threaten to move up north across the border whenever a new president is elected. Maybe it's just that the heat down here makes us more mellow, but I always find people up north to be way more uptight and aggressive.
up North
to or at the northern part of the country or the world. I don't like living up North. I want to move down South where it's warm. When you say "up North," do you mean where the polar bears live or just in the northern states?
up north
to or in the north of a country. informal