Do not come to In Salah in summer. From May through September the daytime temperatures regularly exceed 45°C and have been recorded above 50°C — among the highest temperatures registered anywhere on earth. Travel is impractical, dangerous in the open desert, and most travellers passing through plan their journeys to avoid the worst.
The viable window is October through April. November to February has the most pleasant temperatures — warm days, cold nights — and clear skies. Sandstorms (the harmattan) can roll through from February into spring and reduce visibility for days. Carry plenty of water year-round; even in winter the desert is unforgiving.