The Arctic and Antarctic are way above average temperature:
https://robertscribbler.com/2017/11/...ome-locations/
The melting Arctic ice is weakening the jet stream, and this means that it is much more "wobbly" than it used to be - and this means that colder air is "escaping" much farther south than it used to. This also causes high pressure ridges that stay put for a while, and then move slowly.
The more accurate name for all this is global weirdness - the climate is destabilized, and the GLOBAL average is getting warmer. Most of the heat is in the ocean, and most of the earth is covered with water, so most of the "additional" heat is in the ocean.