Freegrass, I assume that you are aware of the fact that the Western seaboard of Europe and N.America is much warmer than it should be given their latitude. The standard explanation is that the warm North Atlantic Current and the North Pacific Current respectively keep the Western margins of the continents warmer.
In my understanding, the mechanism by which this happens is by primarily by heat transfer via low pressure areas (storms).
I agree with your assumption that the low pressure areas and storms that form in warmer latitudes will lose their heat when they travel north over colder waters. When they travel over warm currents, the low pressure areas lose less heat than when they travel over "normal" waters. Since due to the coreolis effect, the storm tracks and the currents tend to follow the same east-by-north tracjectory, the two of them together cooperate in transferring southern heat to the northern latitudes.
Basically, when a storm enters the Arctic from the south, it has been prevented from loosing all it's heat by the comparatively warm surface waters of the North Atlantic.
Besides maintining a high temperature due to the warm ocean currents, the stormy winds carry a lot of water in the form of droplets, and their heat capaicity is significantly higher than that of the wind itself. The stronger the storm (effectively, the warmer the ocean area where it was formed), the more precipitable water it will carry. And that makes a very big difference to the ice, making rainy storms from the North Atlantic very efficient carriers of heat into the Arctic.
THe kinetic effect of a storm will be stronger in the latter half of the melting season, when there is more open water, but will never be negligible. But I doubt if the kinetic effect matches the heat effect of a storm at any time, although I may well be wrong.
