The khamsin, hot sand-laden winds of the spring months, come invariably from the south.
During a khamsin the temperature is high and the air extremely dry, while the dust and sand carried by the wind form a thick yellow fog obscuring the sun.
The period of the hot winds, called the khamsin, that is, the fifties, is calculated from the day after the Coptic Easter, and terminates on the day of Pentecost, and the Moslems observe the Wednesday preceding this period, called Jobs Wednesday, as well as its first day, when many go into the country from Cairo, to smell the air.
Known in Egypt as the khamsin, on the Mediterranean as the sirocco, it is called on the Guinea coast the harmattan.
Similar winds are met with in Spain (the Leveche), but they reach their greatest development in the Simooms of Algeria and Syria, and the Khamsin of Egypt.