Why are winters generally colder in eastern Europe than in western Europe?

Winters in Europe become progressively colder toward the east due to the interplay of distinct air masses and the diminishing influence of the Atlantic Ocean.12

Western Europe experiences a maritime climate, where the North Atlantic Drift—an extension of the Gulf Stream—and prevailing westerly winds transport warm, moist air from the Atlantic, significantly moderating winter temperatures.134

In contrast, eastern Europe is dominated by a continental climate. As air masses move eastward, they lose the moderating effects of the ocean. Furthermore, during winter, the Siberian high—a powerful high-pressure system centered over Central Asia—often extends westward. This system brings bitter, cold, and dry easterly or northeasterly winds that contribute to the region's harsh winter conditions. The lack of significant mountain barriers in the lowlands allows these continental air masses to penetrate westward, while the mountains that do exist can impede the interchange of warmer tropical and colder polar air.516