Often foreigners have a thought or a prejudice that Finland is extremely cold country. Well, it is partly true, if you think magical Lapland that partly belongs to Finland. But the rest of Finland has often similar weather compared with Central Europe - thanks to the Baltic Sea that warms up. Have a look for example today's weather reports in Finland and Poland.
Sources:
http://www.foreca.fi/Finland/Helsinki/map/fin13
http://www.pogodynka.pl/