Why is it so cold in Harbin?

Harbin has a long winter time and short direct sunlight time all year round. Although spring has arrived in solar terms, in fact, there is no sign of spring yet. It seems that the average temperature for ten consecutive days is above 10 degrees, so it can be judged that spring has arrived. Up to now, there is no weather above 10 degree in Harbin, let alone continuous weather, so it is still the end of winter.

The heating date in Harbin will be April 15, which means it will be cold for a while. In addition, when the snow melts, the temperature will inevitably drop again, so keep warm. Isn't there a saying that spring is chilly and autumn is crisp?