The main reason we can live here at all is the gulf stream. It brings hot water from the Mexican Gulf all the way up along the coast of Norway. Bringing the temperatures up to a resonable level. Still, the difference between summer and winter can be quite remarkable.
Check out the two pictures shot out of my window. One, showing +31 degrees Ceslius (87 F) at the 9th of July 2005. The other one showing -16 degrees Celsius (3.2 F) at the 3rd of February 2005.
One slightly too hot and one slightly too cold. Give me something between -5 and +25 degrees Celsius (23 – 77 F) and I am just fine.