Map from Google - Tajikistan

In Tajikistan the climate is arid continental, with cold winters and hot, sunny summers. Being a mountainous country, the temperature and rainfall vary with altitude and slope exposure. At high altitudes, there are extensive glaciers and snowfields, while the easternmost and the south-western areas are the driest, and are virtually desert. The mountainous areas (Alaj-Turkestan Range in the north, Pamir in the east) in winter receive abundant snow, which later, when it melts, feeds the rivers, and in particular the two great rivers of Central Asia, Amu Darya in the south and Syr Darya in the north. The clashes of air masses can cause wind storms, especially in the period from November to April. The Afghanets can bring dust storms from Afghanistan; in the valleys a down-slope, warm and dry wind, called Harmsil can blow. In the eastern part of the country, which is affected by the Asian monsoon, the wind can cause dust storms even in summer.

Khujand (or Khodzhent) is located in the north, at 350 metres above sea level, in the Fergana Valley, where the Syr Darya flows. Here winter is cold, with an average temperature in January of 0 °C, while summer is hot, since the average in July is 28 °C, with a minimum of 21 °C and maximum of 36 °C. The rainfall is very low, just 170 millimetres per year, with a relative maximum in spring, of 25/30 millimetres per month in March-April, and a minimum in summer (it almost never rains from July to September). While during winter there are intense cold waves, in which the temperature can drop to -20 °C, in summer from June to August the temperature can reach 45 °C.
Here are the average temperatures of Khujand.
Average temperatures - Khujand
Min (°C)-3-2411162021191483-1
Max (°C)461422293436322921126

The capital of Tajikistan, Dushanbe, is located at 800 metres above sea level, in the west, and is moderately rainy because it's located at the foot of the mountains: it receives about 600 mm of rain or snow per year, the majority of which occurs between November and May, with a maximum in March and April, when precipitation is about 110 mm per month, distributed in about 10 days per month, and a summer minimum (even here, from July to September it virtually never rains).
Here is the average precipitation.
Average precipitation - Dushanbe
Prec. (mm)80751101107520131204570610

The climate in Dushanbe is continental, with cold, though not frosty, winters: the average in January is 3 °C. Summers are sunny and hot: the maximum in July and August is around 35 °C, but with peaks of 40 °C. In winter the temperature often drops below freezing at night, but it remains quite mild during the day; however, even here cold waves may occur, with lows around -10 °C, though less intense than in the rest of the country, because the mountains in the north protect in part the city. However, some winters can be very cold, like that of 2008, when the temperature dropped to -19 °C. Here are the average temperatures.
Average temperatures - Dushanbe
Min (°C)-2-14101317181611730
Max (°C)8915222733363430231711


In the south-west, in Qurghonteppa (or Kurgan-Tyube), at 400 metres above sea level, the climate is similar to that of Dushanbe, but more arid, so that only 280 mm of rain or snow per year fall, and more exposed to temperature extremes. The wind that descends from the mountains can cause sudden increases in temperature, with peaks of 45 °C in summer, while in winter the temperature can drop more easily to -20 °C.
Average temperatures - Qurghonteppa
Min (°C)-216121519201712841
Max (°C)111117243036373531221811

The eastern part of Tajikistan (the Gorno-Badakhshan Autonomous Province) is occupied by the spectacular mountainous region of Pamir, the "roof of the world", whose highest peak is the Ismoil Somoni Peak (formerly Communism Peak), 7,495 metres high. The vast plateau is cold, desert and windswept, but in the many areas located above 4,500 metres, snowfalls are frequent, and there are large snowfields and glaciers (among them the huge Fedchenko Glacier). The region is crossed by the Pamir Highway, one of the highest highways in the world, whose conditions, however, are often not good.
In Rangkul, in the east at 3,800 metres above sea level, winter is long and cold, with a January average of -16 °C; still in May, the daily average is 0 °C, and only from June to September the maxima reach or exceed 10 °C, even though the minima remain around freezing, and sometimes may go below, however this period from June to September is the best time of year, especially in July and August when highs are around 13/15 °C. Precipitation is very low, less than 100 mm per year: it is not surprising that the landscape changes directly from the desert to the glaciers of the highest altitudes. The two lakes in the valley, Rangkul and Shorkul, remain frozen for many months of the year, while during summer, near the lakes you can watch several species of migratory birds.
Average temperatures - Rangkul
Min (°C)-22-19-14-8-5021-2-7-13-20
Max (°C)-11-7-225101413102-3-9

More to the north, near the shores of Lake Karakul, at 3,900 metres above sea level, and to the south, near Lake Zorkul, at 4,100 metres, the conditions are similar, with mild days and cold nights in summer, and the lake breeze that during the day can increase the feeling of cold.
Pamir is grooved by deep valleys through which the rivers flow. In the west, we find Khorog (or Chorugh), the capital of the Gorno-Badakhshan Province, which is located at 2,000 metres above sea level, in the valley of the Panj River, and has a continental climate, with cold winters and warm summers: the average in January is -6° C, while the average in July and August is 23 °C. Here are the average temperatures.
Average temperatures - Khorog
Min (°C)-11-9-259121515104-1-7
Max (°C)-11716212730302618102

Here you can go from May to mid-October, bearing in mind that it could be hot during the day in July and August, and cold at night in May and September-October, when the temperature at night can hit freezing. Here the rainfall amount is that of the steppe climate: 235 mm per year, the majority of which occurs from November to May, while even here in summer it almost never rains. Here is the average precipitation.
Average precipitation - Khorog
Prec. (mm)30304040259301102025233


When to go

The best times to visit Tajikistan are spring and autumn, to avoid the weather extremes, and in particular the months of April and October. Between the two, October is preferable, because it is less rainy, especially in Dushanbe and in non desert areas, however, even in these two months, it can sometimes be cold at night and hot during the day. For hiking at high altitudes, the summer is preferable, because it is the only season when the temperature exceeds freezing.

What to pack

In winter : in Dushanbe and the major cities, below a thousand metres, warm clothes, sweater, down jacket, hat, scarf, gloves; some lighter clothes for mild days, scarf for the wind. In Pamir and high mountains, cold weather clothing, synthetic thermal long underwear, fleece, parka, wind jacket, warm boots.

In summer: in Dushanbe and the major cities, below a thousand metres, lightweight clothes, made of natural fabric (cotton or linen), sun hat, scarf for the wind, a sweatshirt for the evening. In the mountains, at intermediate altitudes, light clothes for the day, sun hat, sweatshirt and light jacket for the evening, hiking shoes; above 3,000 metres, sweater and jacket for the evening; above 4,000 metres, down jacket, hat, gloves, scarf.
For women, it is best to avoid shorts and miniskirts.