Guinea is located in western Africa on the Atlantic Coast. At latitudes of 7 to 13°N Guinea has a typically tropical climate. Guinea has one wet season between May and October, peaking between July and September. This rainfall season is largely controlled by the movement of the tropical rain belt (also known as the Inter‐Tropical Conversion Zone, ITCZ) which oscillates between the northern and southern tropics over the course of a year, affecting Guinea when it is in its northern position. There is a strong east‐west gradient in total rainfall received in Guinea at this time, with more than 1000mm per month on the east coast, but less than 150mm per month in the far west due to the south westerly monsoon wind regime. Variations in the latitudinal movements, and intensity, of the ITCZ from one year to another cause large inter‐annual variability in this wet‐season rainfall. The most well documented cause of these variations is the El Niño Southern Oscillation (ENSO). El Niño events are associated with drier conditions in Sahelian Africa. Temperatures in Guinea are lowest in the wettest season, JAS, at 22‐25°C, and around 25‐27°C during the rest of the year.
Source: University of Oxford, School of Geography and the Environment. Accessed on 23 November 2009 at: http://country-profiles.geog.ox.ac.uk/.