Djibouti has an arid tropical climate of semi-desert, except for the mountainous regions of the northern Gulf of Tadjourah. The country is characterized by high temperatures and high evaporation year-round. The country is particularly affected by low and irregular precipitation patterns. The climate is marked by two distinct seasons. The cool season (October-April) has mild temperatures ranging between 22°C and 30°C with relatively high humidity and sea winds. The hot and dry season (May to June and September to October) has high temperatures, which can range between 30°C and 40°C with often violent, hot and dry sand wind (khamsin). The wettest months are April, July, and August, with a monthly average of 30 mm. January, June and December are the driest months, with average rainfall of 10 mm or less. Rainfall is largely regulated by the Inter-Tropical Convergence Zone (ITCZ) and the climate is also susceptible to the impacts of the El Niño Southern Oscillation (ENSO). The country also experiences occasional catastrophic floods.
- Djibouti experienced temperature increase since the 1970s, with the southern and western regions observing the most significant temperature rise
- An increase of between 0.5°C and 1.5°C has been observed in the absolute maximum monthly temperatures in the past three decades. The average increase in minimum temperature is 1.5°C and the increase is most significant in June and July.
- The number of warm nights has increased dramatically. The greatest warming was observed during the summer hot season. A reduction in cool nights and increase in warm nights since 1960 have been observed.
- Precipitation in Djibouti is highly variable and overall, the country experiences very low levels of annual precipitation. Djibouti has experienced reduced water availability in some areas and increased periods of drought and dry spells.
- Stronger precipitation events resulting in flash flooding in recent years has also been observed due to an increase in heavy precipitation events.
- Djibouti has also experienced an increase in aridity across the country and intense droughts, the most significant occurring in 1989, 1994, 2004 and 2005.
- Significant decrease in rainfall has been registered for the months of April-July since 1960.
- Significant increase in rainfall has been registered for the months of January and October since 1960.