Finally, the sun is out, after days of pouring rain. According to a WWF analysis of the climate in Europe, the cities are getting warmer due to increased use of energy and climate changes. As an example, the average temperature in Europe rose by 0.95 celcius during the last century. Specifically for Helsinki, the mean daily summer temperature in 1970-1974 was 15.2 degrees celcius. In the years 2000-2004, it rose to 16.0 degrees.
If this worries you, I suggest you check this out.