South Korea has a continental climate characterised by very cold, dry winters and very hot, humid summers. Spring and autumn are virtually non-existent, summer arriving suddenly in late April and winter setting in late in October. Temperatures in winter are usually below freezing, exacerbated by cold winds from Siberia, while summers are warmed by moist, warm prevailing winds from the Pacific Ocean. Between June and September the weather in South Korea is very wet, and typhoons are possible.