The best time to go?
Varies depending where you want to go. The geography of the country means that as winter starts to come in the mountains get shut off by snow. There are a few vehicles that can get through but they go in convoy and it is a major undertaking. That means if you visit Tajikistan you need to go from Spring to early Autumn.
Spring carries with it a set of difficulties for getting round the country and trekking – the snow melt means usually a lot of flooding, high rivers and landslides – it is however the best time to see flowers. Summer is hot – cloudless skies and on the lower plains in the Khaton Region it is scorching – averaging 42C daily. Dushanbe is usually about 5C cooler but it is still hot.
Early Autumn is perhaps the best time to get around avoiding the heat but it would be important to make sure you get out of the mountains or remote regions before the weather closes in.