Bhutan's weather is shaped by two things above all: altitude and the monsoon. Because the land rises from around 200 metres in the south to over 7,000 metres in the north, you can pass through several climate zones in a single day's drive.
Climate zones
The southern foothills are hot and humid subtropical, with heavy summer rain. The central valleys — Paro, Thimphu, Punakha and Bumthang — are temperate, with warm days and cool nights and a comfortable climate for most of the year. The high north is alpine: cold, snow-bound in winter, and home to yak herders and the great high-altitude treks.
The seasons at a glance
- Spring (Mar–May): mild, flowers in bloom, occasional pre-monsoon showers.
- Summer (Jun–Aug): warm and green with the monsoon; rain is often confined to afternoons and evenings.
- Autumn (Sep–Nov): dry, clear and stable, with the best mountain views of the year.
- Winter (Dec–Feb): cold and sunny in the highlands, pleasant in the warm south.
Whatever the season, temperatures drop sharply after dark above 2,500 metres, so warm layers are essential year-round.