Westerly storms warm Norway and is more important than the Gulf Stream and it's extensions, and the vast volume of water in the Norwegian sea stores heat and warms Norway and other surrounding areas in winter.
Westerly storms warm Norway - The Research Council of Norway
Northerly winds pushing sea water south in the Denmark strait pulls warmer water north into the Norwegian sea and is possibly more important than the Gulf Stream:
Cold wind makes Norwegian Sea warmer
Notice that the Norwegian sea is a deep-water sea - average depth is 2 km.
This contrasts with the North Sea to the south or the Barents sea to the northeast - both of these are shallow seas.
Norwegian Sea - Wikipedia, the free encyclopedia