Climate Profile of Bhutan
Seasons:
The four seasons recognizable for Bhutan are – the winter season from December to February; spring from March to May; summer monsoon season from June to September; the autumn months of October and November.
The Southwest or summer monsoon, contributing about 80% of the annual rainfall, is from June to late September. Rainfall is highest in July followed by August. The spring (March-May) and autumn (October-November) period contributes about 20% of the annual rainfall.
| Sr. No | Seasons | Months |
| 1. | Winter | December, January, February(DJF) |
| 2. | Spring (pre-Monsoon) | March, April, May (MAM) |
| 3. | Summer Monsoon | June, July, August, September(JJAS) |
| 4. | Autumn (post-monsoon) | October, November (ON) |
Figure 2. below illustrates the monthly variations of temperature – maximum, minimum and mean, and rainfall over the whole of Bhutan. The seasonal cycle clearly indicates the predominant climate regime of rainy and warm summer months and cool (<10°C) winters interspersed by the transitional seasons.
Figure 2. Seasonal Variation of temperature- Maximum (Tmax), Minimum (Tmin) and Mean (Tavg.) and rainfall (mm) over Bhutan as a whole (based on the stations observation for the period from 1996-2013 for 44 number of stations)
Climatology for Dzongkhags of Bhutan
The climatology for the 20 districts of Bhutan was prepared using the climate data (Tmax, Tmin and Rainfall) over the period from 1996-2013. The good quality climate data from station (A, C and intermediate) was used to calculate maximum, minimum, average temperature and mean precipitation amount for each month of the year.
Climatology of Bumthang
