Tropical climates with well-distributed rainfall are found in parts of the East African lakes region and southwestern Ethiopia. In the lakes region there is little variation throughout the year in the mean temperature and humidity, ranging from 60-80F or 16-27C and 80 % respectively varying with location.

The rainy season gets shorter, rainfall decreases, and is confined to July and August in the northern part of central Sudan. Three seasons may be distinguished. The first of these is the pleasant, cool, dry winter, which occurs from December to February; this is followed by hot and very dry weather from March to June; and this is followed, in turn, by a hot rainy period from July to October.

North of Khartoum less than 5 inches of rain falls insufficent to sustain life permamnently, while 10 inches fall in the Al Jezirah region between the two niles.
In June and July the central parts of The Sudan are frequently visited by squalls of 2-3 hours duration, called Haboobs, carrying large quantities of sand and dust.

A desert-type climate exists over most of the remainder of the area north to the Mediterranean. Northern Sudan and the desert of Egypt are arid, with dry atmosphere, and a considerable seasonal, as well as diurnal, temperature range in Upper Egypt. Winter temperatures decrease to the north. During the Spring, from March - June, depressions from the Sahara or along the coast travel east, causing dry southerly winds, which sometimes results in a condition called khamsin. These are sandstorms or dust storms during which the atmosphere becomes hazy; persist sometimes for three or four days, at the end of which the phenomenon of a "blue" sun may be observed.