The focus in Africa this week is Benin, which has received a month of heavy rainfall. Severe flooding has killed thousands and displaced more than one million people in the Gulf of Guinea region. Benin, Togo, Ghana, Côte d'Ivoire and Nigeria have all been impacted. Elsewhere, dry weather remains firmly in place across eastern and southern Africa. Seasonable conditions are now in place across the north.
The oceans around the world are greatly influencing what is occurring in east and west Africa right now. Warmer than normal water off the west coast of Morocco is responsible for the flooding occurring across the Gulf of Guinea region. Meanwhile a cool water off the coast of Somalia paired with warm water near Indonesia is causing dry weather across Somalia, Kenya and Ethiopia. I plan to give both of these phenomenon their own post in the near future, so stay tuned. For now lets just worry about the end result.
The wet weather in the east has destroyed infrastructure, crops and caused fatalities in Benin, Togo, Nigeria, Ghana and Côte d'Ivoire. Thus far Benin has received the brunt of this event, partially due to dams breaking in countries up stream. It is possible that the flooding could shift somewhere else in the region, if the rains move elsewhere. Precipitation surpluses extend across all of west Africa. A key concern now is the spread of water-borne diseases. As the one month precipitation anomalies image from the Climate Prediction Center shows, all of west Africa has been soaking wet for several weeks.
Meanwhile in Kenya, Ethiopia and Somalia, dry weather is wilting crops and reducing access to drinking water. Although some isolated locations, primarily in western Ethiopia and western Kenya, have received sufficient precipitation to keep totals near climatology (and some locations are even above climatology) the vast majority of the region has seen deficits expand over the last week. Mogadishu, Somalia is representative of many locations in the region. In the time-series graphic from the Climate Prediction Center the dashed line represents cumulative rainfall climatology, while the solid line is cumulative estimated rainfall. at Mogadishu rainfall deficits are now approximately 25 mm or 1 inch. In this arid climate, that is a significant deficit during what is only a three month rainy season.
In the south, although it has been dry in the short-term, things are likely to change and become wetter during this rainy season. This, once again, is attributed to sea surface temperatures. In the short-term, however drinking water availability and pasture for farm animals may be scarce. Rainfall did make it's way across the important crop areas of South Africa during the last week, and it appears that another round of precipitation is likely during the coming week.
Northern Africa remains near normal to slightly wetter than normal. There is the possibility of temperatures slipping below freezing (OoC and 32oF) during the overnight hours in the higher elevations of the Atlas Mountains in Morocco.