Malaysia has a hot, humid tropical climate with small temperature variation through the year and frequent rainfall in most areas. The country is dominated by Köppen Group A climates, mainly tropical rainforest and tropical monsoon, with temperatures generally staying above 18 C in every month and rainfall commonly above 1500 mm annually. Lowlands and coasts feel warm to very warm year-round, while highland areas are noticeably cooler and more comfortable. For residents and expats, the biggest climate differences are between the wetter east coast and Borneo, the somewhat less monsoon-exposed west coast, and the cooler highlands.