Papua New Guinea has a hot, humid tropical climate year-round, but its steep mountains, coastal plains, and many islands create strong local differences. Most lowland areas are tropical rainforest or monsoon climates, while the central highlands are much cooler because of altitude and can feel chilly at night. The country has a wet season and a dry season rather than four distinct seasons, and rainfall is heavy in many places, especially in the highlands and on windward coasts. For residents and expats, the biggest climate factors are persistent humidity, intense rain, and cooler high-altitude conditions in the interior.