Weather & Climate

Five climate zones in a country the size of Switzerland, and why the forecast changes every hour of the climb.

The single most useful thing to understand about Bhutan's weather is that the country is small but almost entirely vertical. Paro sits at about 1,330&nbsp;m. Thimphu is at 2,334&nbsp;m. The Phobjikha valley is at roughly 3,080&nbsp;m. The high passes on northern trekking routes exceed 5,000&nbsp;m. A route that looks like a short drive on a map can cross every climate zone in the Himalaya. <h2>Five climate zones</h2> Bhutan is conventionally described in five climatic bands, running north to south: Tropical — the southern foothills and Duars, hot and humid year-round. Subtropical — wide mango and banana belts, including Phuentsholing and lower Samtse. Warm temperate — the main inhabited valleys: Paro, Thimphu, Punakha, Bumthang. Rice terraces, mild summers, cold winters. Cool temperate — higher valleys such as the upper Bumthang and Haa regions, with conifer forest. Alpine — above roughly 3,800&nbsp;m, where there are no permanent settlements and only seasonal herders. <h2>The seasons, and what actually changes</h2> <h3>Spring: March to May</h3> The most popular window, and for good reason. Rain has not yet started, the air is clear, rhododendrons bloom across the highlands in Apri.