Jeju in December

April through June brings perfect weather — warm days, cool nights, and cherry blossoms that rival mainland Korea. Hotel prices stay reasonable, and hiking trails aren't crowded yet. May hits the sweet spot with average temperatures around 20°C. September through November delivers Jeju's second prime season. Typhoon season ends, autumn colors paint Hallasan, and tangerine harvest begins. October offers the best hiking weather of the year. Summer (July-August) means crowds, humidity, and typhoon risk. But beach weather peaks, and families with school-age kids have no choice. Book accommodations months ahead and expect premium prices. Winter stays mild compared to mainland Korea, but wind makes it feel colder. January temperatures hover around 8°C. The upside? Fewer tourists, cheaper hotels, and crystal-clear views of Hallasan's snow-capped peak.