Hi, I just moved to Sweden and its surprisingly warm here during the Summer - and throughout the whole year.
Really, I thought is super cold there during the winter.
I thought the same thing - but as I learned very recently - the climate here is heavily influenced by oceanic winds. 
oooo that makes sense, but doesn't it snow a lot there?
Depends on if you live in northern or southern Sweden: in the north it's like Siberia; in the south it snows a few times a year but quickly melts away in days or weeks.
Wow, do a lot people live in the North of Sweden?
Well to give you an idea, the heavily populated capitol city of Stockholm is on the south-eastern coast.  The north has a lot of forests; and the south has a lot of farming.
I see, that makes sense. How is Stockholm, I heard its a nice small city.
Stockholm
Stockholm () is the capital of Sweden and the most populous urban area in the Nordic countries; 965,232 people live in the municipality, approximately 1.6 million in the urban area, and 2.4 million in the metropolitan area. The city stretches across fourteen islands where Lake Mälaren flows into the Baltic Sea. Outside the city to the east, and along the coast, is the island chain of the Stockholm archipelago. The area has been settled since the Stone Age, in the 6th millennium BC, and was founded as
can be considered as a summer resort in Hong Kong(since Hong Kong is usually really hot during summer); the spring is cool to cold but very humid, while the autumn is cool and dry, but also because of its climate similar to Tai Mo Shan, winter might experiences frost and snow and other winter special weather phenomena, even more than Tai Mo Shan and Ngong Ping also much more cold (because it is isolated from urban areas and often experiences strong winds throughout the year). Because there is no weather station