The weather and temperatures in Colorado are quite different compared to most of the United States. In most other states, the southern part is warmer than the northern part, southern Colorado is not noticeably warmer than northern Colorado. Mountains and surrounding valleys greatly affect local climate. As a normal rule, with an increase in height comes a decrease in temperature and an increase in rain. There exists a phenomenally severe change in climate in Colorado between the Rocky Mountains on the west and the Great Plains on the east, both of which are separated by a lesser range known to Colorado citizens and primarily Boulderites as "the Foothills".