The short answer: between October and April. From May to September daytime temperatures in the deep south regularly pass 40°C, and most desert trips stop.
October and November
Warm days, mild nights and very clear light. This is our favourite time for the Tassili plateau trek.
December to February
Perfect daytime temperatures in the low 20s, but nights in the Hoggar and on the Tassili can fall below zero. Bring a good sleeping bag — we provide extra blankets.
March and April
Longer days and the occasional sandstorm. Spring is also lovely in the north, so it is a good time to combine the Sahara with Algiers or Constantine.