The climate of Bhutan is dominated by the monsoon which brings rain from June to the end of September, so this is the main time to avoid Bhutan, but local conditions are affected by altitude.  After the monsoon the air is clear and fresh with autumn temperatures reaching up to 30’C. Winters in the inhabited valleys are generally dry with daytime temperature ranging between 15 – 20’C but visitors in January and February should be prepared for cold nights when the temperature falls below freezing.  Black-necked cranes migrate to the Phobjika Valley in late October and usually leave by mid-Feburary. By the end of April the heat and humidity begins to build until the rains fall again in June. A couple of big festivals take place in spring and autumn. The spectacular Paro Tsechu in March or April and the Thimphu Tsechu in September when costumed and mask-wearing monks perform ritual dances attract large numbers of foreign visitors and beds are high sought after. If you can’t make it to one of these festivals there are smaller celebrations somewhere in Bhutan almost every month.