Sudan cannot currently be visited safely. The following describes when to go once travel becomes possible again.
Sudan spans four climate zones, from desert in the north to semi-arid savannah in the south. The determining factor for most travelers is heat, which can be brutal.
October to February is the best time for most of the country. Temperatures are manageable — days are warm but not dangerous, nights can be surprisingly cool in the north, sometimes cold enough for a jacket in the desert. The sky is clear and the light is good for photography. This is when the Nile route through Nubia is most pleasant.
March to May brings rising heat. By April and May, temperatures in Khartoum regularly exceed 40°C, and the northern desert can hit 45°C or more. These months are uncomfortable and increasingly dangerous in the heat.
June to September is the rainy season across central and southern Sudan — the rains come from the south and move north, reaching Khartoum by July and August. During this period, desert tracks become impassable, the Nile floods, and the humidity in the central belt is oppressive. The north remains dry but scorching.
The Kassala region and the Red Sea hills have a slightly different rhythm — the east catches some moisture from the Red Sea and can be pleasant in the cool season. Port Sudan diving is best in the calm months of October through April.
Dust storms — haboobs — can arrive without much warning at any time of year, particularly in the hot season around Khartoum. They are spectacular and unpleasant in equal measure.