Well above-average seasonal rains result in widespread flooding across East Africa
• The onset of the October to December seasonal rains were generally much earlier than normal. Rainfall in October was well above average, resulting in widespread flooding that caused human fatalities, some crop and livestock losses, and property damage. The worst-affected areas are primarily located in southern Somalia, eastern Ethiopia, Kenya and eastern South Sudan. More than 700,000 people have been displaced in Somalia, Ethiopia, and Kenya since early October. In South Sudan, more than 900,000 people have been affected by flooding since July.
• In the medium-term, the heavy rainfall is expected to benefit crop and livestock production in parts of the Horn, namely within Somalia and Kenya. Outside of flood-prone areas, the rains have been largely beneficial to crop production and regeneration of rangeland resources, especially after prolonged severe drought conditions over the eastern Horn.
• The exceptional performance of the rainfall season is largely influenced by an exceptionally strong Indian Ocean Dipole (IOD), currently at +2.1oC. The IOD event is one of the strongest in the recent 20-year record. The super-charged IOD is expected to be sustained through the peak of the Deyr/short-rains season in November.
• The rainfall outlook for November is forecast to be above average. This is the peak rainfall period of the Deyr and short rains in the eastern Horn. With the rainfall, there is a heightened risk of additional flooding in the coming weeks.
The October seasonal rains performance was generally characterized by earlier-than-normal onset (10-20 days) and episodic, well above average rainfall. Rainfall was more than 200 percent of normal in many areas, with anomalies ranging from 50 to 300 mm (Figure 1). The excessive rainfall resulted in widespread riverine flooding and localized flash floods. Worst-affected areas are primarily located in southern Somalia (Belet Weyne district of Hiiraan and lower Shabelle and Juba river basins); northeastern and eastern pastoral areas of Kenya; southeastern Ethiopia (Afar, Oromia, SNNPR and Somali regions); and eastern South Sudan (Greater Upper Nile and Great Equatoria regions).
Other affected areas include parts of eastern Uganda and Tanga region of eastern Tanzania.
More than 700,000 people are reportedly affected by the recent floods across Ethiopia, Somalia, and Kenya, according to recent UNOCHA reports. 48 deaths were reported in Kenya with 144,000 affected by floods, especially in Wajir and Marsabit counties. In Somalia, more than 370,000 have been displaced, primarily in Belet Weyne of Hiraan region. In South Sudan, more than 900,000 people have been affected by flooding since July, particularly in Maban of Upper Nile and Pibor of Jonglei. Humanitarian response is ongoing in most affected areas, which was facilitated by a brief dry spell in late October and early November in Somalia and Kenya that relatively improved road access.
Despite some livestock loss in Kenya and the interruption of planting activities in riverine areas of Somalia, the above-average rainfall has been largely beneficial for rangeland and cropping conditions. The rains are facilitating regeneration of pasture and water resources and supporting crop development in areas that suffered drought and crop failure in late 2018 and early 2019 in the eastern Horn. Based on the eMODIS Normalized Difference Vegetation Index, vegetation conditions have significantly improved compared to September. Greener-than-normal vegetation conditions are observed in Sudan, eastern and southern Ethiopia, southern Somalia, northern and parts of eastern Kenya, northeastern Uganda together with much of eastern coastal regions of Tanzania. In northeastern Somalia, localized areas of eastern Kenya, and central Tanzania, however, conditions have remained dry and negative vegetation anomalies persist. In Rwanda, Burundi, and southwestern Uganda, vegetation conditions are generally obscured from satellite view by persistent cloudiness, which is indicative of on-going seasonal rains.
Early season field reports across the eastern Horn are indicative of favorable cropping conditions at early vegetative stages in agropastoral regions of eastern Kenya, southern Somalia, and northeastern Tanzania. However, there are some confirmed reports of presence of FAW in some of these areas following the dry spell experienced in late October into early November, especially over parts of southeastern Kenya. According to FAO, a desert locust infestation is ongoing in Ethiopia, despite ground and aerial control operations. The mature swarms are devouring crop and pasture fields in Tigray, Amhara, Oromia, Afar and Somali regions.