Subject: Finland and Norway
Weather in Helsinki and elsewhere in southern parts of Finland and Norway is usually warm at the end of July, about 75-90 degrees but of course it's possible that it's only around 50. In the north it's colder, maybe 45-55 degrees but it can also get colder (or warmer). Since you are not used to such temperatures and conditions, it's better to take warm clothes with you. I'm not quite sure what a polartec jacket is but if it's very warm and thick, then you don't need a warm sweater. Another alternative is a windbreaker and a warm sweater. Both the jacket and windbreaker should have a hood. Thermals may be good especially for legs (though here hardly anybody wears such things) and of course you need something for neck and hands, also warm socks.

Tuija in Finland