You can travel in Bhutan at any time of the year except during the winter which starts in December and ends in early March. During the summer, you should expect some light rainfall expecially in the south of Bhutan. In the winter time, the temperature can drop down to -6 degrees Celsius while in the summer time the temperatures reach an overage of 25 degrees Celsius. The best time to travel in Bhutan is during the Spring (March, April and May) as days are warm and clear.Bhutan has a wide range of climates, from the hot and humid jungles of the southern foothills to frigid snowcapped peaks in the north, which rise to 7,700 metres.
Broadly speaking, we can divide the climate of Bhutan into four seasons: Spring, Summer, Autumn and Winter. Spring begins by the end of February and lasts till the end of May. Summer starts by the end of May and lasts till the end of August. There is one more season that may be identified in between somewhere here. The rainy season starts by June and lasts till the middle or end of September. The rainy season more or less coincides with the summer season. The rainy season is vital for farmers to grow their crops like maize and rice, but it causes roadblocks due to landslides. Sometimes, you may be stranded on the highway for hours or for a few days due to roadblocks. Autumn starts by October and lasts till the end of November. Winter lasts from December to February. In most places in Bhutan, it snows in winter except in Southern Bhutan. Even in the south, it is quite chilly in the morning and evening in winter. Summer is quite hot everywhere. But in the south, it gets almost terribly hot. Spring is a good season. Rainy season is not much loved by the city dwellers.
Bhutan's climate varies significantly with altitude and between specific locations. There are three broad climatic zones: subtropical in the south, temperate in the broad central regions and alpine in the north. Rain is concentrated in the monsoon season from June to September. Bhutan has four distinct seasons. Each has its advantages and disadvantages for the visitor. Notice should be taken of the unpredictable weather patterns before making decisions when to visit. Remember even predictable weather can vary dramatically in different areas and in 24-hours periods.
Spring is arguably the most beautiful time of the year in the kingdom. The fierce cold that is characteristic of the winter months tends to subside towards the end of February (around Bhutanese New Year, Losar). Rhododendrons begin to bloom, first in the warmer east .At the height of spring, the end of March; the whole kingdom comes to life with spectacular flaming red, pink and white of the rhododendron blossom. The monsoon brings rain from the Bay of Bengal in the month of June, mostly affecting the south and centrals regions. The north is inhabited in the summer months when the nomads return to the higher plains to tend to there Yaks.
End of the monsoon, is also a popular time to visit, marking the ending of summer. Days are filled with glorious cobalt skies. The autumn months of September to November bring shorter days and cooler evenings. The days remain lovely with crisp clear skies. Views over the high Himalayas are usually only possible from September to March. Come the end of November and the weather takes on its winter coat. Days remain crisp and nights turn cold. The southern regions, being much lower have a more temperate climate and considerably warmer winters. Clear skies in the winter months bring with them cold weather but it's also the best time of the year to view the snow covered peaks of the high Himalayas.
