Geography of Helsinkihas a total area of. of it is land and of the area is covered with water. It is located at.SubdivisionsThis is a listing of the neighborhoods and localities in the city of Helsinki in alphabetical order. The list is not complete.ClimateAverage temperature : +5.9 °C Warmest month, July, average temperature: +17.2 °C Coldest month, February, average temperature: -4.7 °C