Passage: Most of the country is hot in the summer and extremely cold in the winter, with January averages dropping as low as −30 °C (−22 °F). A vast front of cold, heavy, shallow air comes in from Siberia in winter and collects in river valleys and low basins causing very cold temperatures while slopes of mountains are much warmer due to the effects of temperature inversion (temperature increases with altitude).

Question: Averagely how cold can January get in most parts of the country?
−30 °C (−22 °F)