Taiga

After tundra and permanent ice caps, the taiga is the terrestrial biome with the lowest average annual temperatures.

An excerpt from the article 19 facts about Taiga
The average annual temperature ranges from -5 to 5 °C (23 °F to 41 °F). In the Siberian taiga, the average temperature of the coldest month ranges from -6 °C to -50 °C (21 °F to -58 °F).