Eastern Georgia has a transitional climate from humid subtropical to continental. The region's weather patterns are influenced both by dry Caspian air masses from the east and humid Black Sea air masses from the west. The penetration of humid air masses from the Black Sea is often blocked by mountain ranges (Likhi and Meskheti) that separate the eastern and western parts of the nation. The wettest periods generally occur during spring and autumn, while winter and summer months tend to be the driest. Much of eastern Georgia experiences hot summers (especially in the low-lying areas) and relatively cold winters. As in the western parts of the nation, elevation plays an important role in eastern Georgia where climatic conditions above  are considerably colder than in the low-lying areas.