Inner Mongolia has a temperate continental climate. There, spring is warm and windy; summer is short and hot with many rainy days; autumn usually sees early frost and plummeting temperature; winter is long, bitter cold with frequent polar outbreaks. The region has an annual precipitation of 100-500 mm, 80-150 frost-free days, and 2,700 hours of sunshine. The Greater Hinggan Mountains and the Yinshan Mountains divide the regions into areas with different climate. The area east of the Greater Hinggan Mountains and north of the Yinshan Mountains has lower temperature and less precipitation than the opposite area.