Despite its relatively small land area, the climate in Tajikistan varies widely, due to the country's mountainous topography. The climate in Spring (March-May) and Autumn (September-November) is moderate. In the cities, daytime temperatures average around 20-30°C. Summer can be ferociously hot in the cities (daytime maximum temperature often exceeds 40°C). The southern cities of Qurghonteppa and Kulob are noticeably hotter than Dushanbe. Only the mountainous Regions are quite cooler. Occasional dust storms, especially in the lowlands, can make life unpleasant.
Winter is usually quite mild, but expect some snowfall in the valleys between December and February. In the mountains, however, conditions are harsher with low temperatures, snow and strong winds and the higher mountain passes are often closed.
Lightweight clothes are advised for the summer months, medium- to heavyweight clothing is neccesary during the winter. Wherever you go, take a sweater for cool evenings, the difference between maxima and minima can vary significantly.
The climate of Tajikistan can be divided in three different climate zones. The western lowlands have a BSk climate; a cold Steppe climate with an annual average temperature lower than 18°C; the region nearby the Pamir mountains have a Csa climate, a moderate temperated climate with a dry summer, the coldest month between 18 and -3°C and the warmest month over 22°C. The mountainous region itself has a humid snow climate with the warmest month under 22°C, more than four months above 10°C and the coldest month below -3°C.