Afghanistan is an arid and dry country with a pronounced continental climate. The climate varies greatly with the location of the place.
Afghanistan is a mountainous country and a network of mountains is spread all over its territory. The climate of a particular area therefore depends very much on its height and location. Kabul, the capital, for instance, located at a height of 6000 feet has a very cold winter and a warm summer. Jallalabad, in comparison located on the eastern plains has a cool winters and very hot summers with temperature often reaching 110 F ( 43 C ). Kandahar to the south east located at an elevation of about 4000 feet has a climate which falls mid way between Kabul and Jallalabad. The winters are less severe than that at Kabul and summers though hot are rendered moderate by height.
The precipitation, every where in Afghanistan, is very scanty. In hills it is mostly in the form of snow. Kabul gets snowfall in winter due to western disturbances, an extra tropical depression which crosses Afghanistan from January to March. The winter precipitation accounts for more than 80% of the precipitation of Afghanistan.
In short the climate of Afghanistan is an extreme form of continental climate with hot summers and cold winters. If you want to visit Afghanistan then these seasons must be avoided. A good approach would be to visit this country during spring and fall when the temperatures are within tolerable limits and the weather is sunny and dry.