Poor rainfall across East Africa has increased rainfall deficits amid drought conditions

• Prolonged dryness and exceptionally hotter-than-normal conditions have persisted across much of East Africa since January, driving severe deterioration in rangeland resources (pasture and water) in the eastern Horn. 

• There is deepening concern for a fourth sequential poor rainfall season given the delayed onset of the rains and widening of cumulative rainfall deficits, especially over pastoral areas of the Horn, Ethiopia’s belg cropping zones, and parts of the equatorial sector of the region. Such a four-season shock would be unprecedented on the historical record.

• CHIRPS rainfall estimates for the month of March and forecast rainfall through mid-April indicate below-normal rainfall across much of East Africa. Rainfall anomalies of -10 to -200 mm are widespread, with much of the Horn recording less than 60 percent of average rainfall. Rainfall in April, the peak of the gu/long-rains season, is likely to be below average over the eastern Horn, driving the continuation of poor crop and pasture conditions.

From January to mid-March, unseasonably hotter-than-normal conditions persisted across East Africa, apart from Tanzania, which experienced above-average Msimu seasonal rainfall. Hotter-than-normal land surface temperatures, especially over the eastern Horn, helped drive the rapid deterioration of rangeland resources (pasture and surface water), and the continuation of poor livestock conditions and productivity in gu/long rains receiving pastoral and agro-pastoral areas.

From mid-February to March, the tropical rainfall belt slowly and unevenly moved northwards from southern and central Tanzania into Burundi, Rwanda, south-east Uganda, and the neighboring regions of southern and western Kenya. In March, less than 50 mm of rainfall has been recorded across most of Kenya and Somalia and southern and eastern Ethiopia, marking a delayed onset of the gu/long rains season. In belg (mid-February to May) rain-dependent areas of Ethiopia, rainfall is delayed by two to three dekads and significantly below-average, with rainfall 75 percent of average or less (Figure 1). In Uganda, Rwanda, and Burundi, rainfall in March has also been less than 75 percent of normal. However, across most of eastern Tanzania, Kenya, southern and northeastern Ethiopia, and southeastern South Sudan, cumulative rainfall in March is less than 60 percent of average. The largest rainfall deficits for March were observed in southern and eastern Kenya and southwestern and northeastern Ethiopia, where cumulative rainfall in March is less than 45 percent of average.

Regional forecasts indicate that rainfall deficits are likely to increase in the first half of April, with deficits as large as 30 to 60 percent of the average across most of Kenya, Somalia, Ethiopia, northeastern Uganda, southeastern South Sudan, and eastern Tanzania (Figure 2). These early-season rainfall deficits, coupled with the delayed onset of the rains, are of increasing concern and will likely result in an unprecedented fourth consecutive poor agricultural season. Cumulative rainfall deficits of less than 30 percent are also likely to occur in the pastoral and marginal agricultural areas of northern and southeastern Kenya, the Shabelle/Afder districts of the Somali Region, Ethiopia, and the Dire Dawa and Afar regions of Ethiopia.

Vegetation conditions measured by the Normalized Difference Vegetation Index (NDVI) are significantly drier-than-normal in northwestern Uganda, northern and eastern Kenya, southern and central Somalia, and several areas of Ethiopia, including part of the Rift Valley areas of Afar as well as SNNPR, Sidama, Somali, and southern and central Oromia regions (Figure 4). Since late 2020, rangeland resources and livestock conditions in Kenya, Somalia, and Ethiopia have deteriorated due to below-average rainfall and hotter-than-normal conditions during the ongoing drought. The rest of East Africa is currently experiencing near-normal vegetation conditions, with greener-than-normal vegetative conditions along Kenya's southern border and along the Nile River basin in South Sudan and eastern Sudan.

Although the cropping season is yet to be fully established in areas dependent on the long rains, crops in Rwanda, Burundi, and parts of the Uganda/Kenya border areas are in favorable condition due to a timely to early onset of rains in the preceding dekads.

According to the FAO, there is a low presence of desert locusts in the region, apart from isolated sightings in northeastern Sudan. The region's lack of conducive environmental and weather conditions is likely to maintain a low presence of desert locusts.

The following is a country-by-country update on recent seasonal progress to date:

• In Somalia, the 2022 gu rains typically start in early to mid-April. Rangeland resources have rapidly deteriorated due to prolonged drought and exceptionally hotter-than-normal conditions, leading to massive livestock migration and increased grazing pressure in the few areas where green or dry pasture is still available. This has adversely affected livestock body conditions and milk production, ultimately resulting in excess livestock deaths from starvation and disease. The worst-affected pastoral areas are in central and southern Somalia. While pasture availability is relatively better in northern Somalia, it has attracted large volumes of livestock in-migration, and pasture is rapidly depleting. Meanwhile, low water levels in the Shabelle and Juba rivers is preventing irrigation in riverine cropping areas. As a result, farmers have mostly suspended cash crop and off-season farming, apart from some sesame production in flood recession areas.
• In Ethiopia, belg/gu/genna seasonal rains are predominantly characterized by delayed onset and associated early season rainfall deficits. Delayed planting and a shortened crop growing window for belg/gu/genna crop-producing areas will likely affect crop production and rangeland resources.
• In Kenya, the 2022 long-rains season started early over western regions of the country, but there is a delayed onset in eastern Kenya, particularly along the coastal strip. There are increasing concerns for below-average rainfall in April, which would result in another below-average agricultural season in eastern, southeastern lowland, and coastal regions. In pastoral areas, rangeland resources are continuing to deteriorate due to the delayed start of the long rains across northern and eastern Kenya and high land surface temperatures. This is continuing to adversely affect livestock body conditions and production, including excess livestock deaths
• In Sudan, land surface temperatures remain hotter than normal, especially over its eastern and northern regions. No rainfall is forecast during the typical dry period, and pasture and browse are likely to deteriorate. There are localized reports of desert locusts in the country's northeastern regions; however, they are unlikely to be a threat due to prevailing poor environmental and meteorological conditions.
• In South Sudan, a delayed start to the first season rains has led to significant rainfall deficits in the southern bimodal cropping areas of the country. Drier-than-normal vegetation conditions are becoming more evident due to hotter-than-normal conditions during the typical dry season. However, short-term forecasts indicate that the April rains are likely to be above average to average, which will likely improve rangeland resources and support planting. However, the benefits will likely be offset by heightened flood risk in downstream areas of the Sudd region, where soil moisture remains above average and floodwaters from the 2021 rainy season still linger in some areas.
• In Uganda, southern and Lake Victoria regions observed an early onset of seasonal rains in early to mid-February, supporting favorable cropping conditions for planted crops. However, below-average rainfall across the rest of the country is delaying the planting season. In northern and western Uganda, vegetation conditions are drier-than-normal due to the delayed onset and abnormally hot land surface conditions. However, rangeland conditions are likely to gradually improve following the forecast average to above-average rainfall in April; however, heavy rainfall around the slopes of Mt. Elgon is likely to elevate the risk of flash floods.
• In Rwanda and Burundi, the season B rains started in February in a timely manner and are well distributed across most parts of Rwanda and Burundi. Overall, crops are in vegetative stages and in good condition. However, early-season rainfall deficits are present in localized areas of southern Burundi. Meanwhile, localized floods have affected Rwanda's Northern Province and delayed planting. Vegetation greenness across both countries is near-average, with localized areas of drier-than-normal conditions.
• In Yemen, a late start to the March-May seasonal rains is driving below-average cumulative rainfall across most of Yemen, apart from localized areas of above-average rainfall in western Yemen. However, drier-than-normal conditions in the western highlands are resulting in declining vegetation greenness. Current vegetation conditions are mixed, with below-average vegetation greenness in western Yemen and average to slightly better than average vegetation greenness across the rest of the country. 

Global and regional rainfall forecasts indicate a greater probability of below-average rainfall in April over much of the eastern Horn. This is typically the peak of the seasonal rainy season, with another poor season likely to significantly impact agricultural and pastoral livelihoods. Meanwhile, the southern, western, and parts of the northern sector of the East Africa region are forecast to maintain above-average to average rainfall in April, supporting favorable cropping conditions, but with elevated flood risks around Mt. Elgon in eastern Uganda/western Kenya, localized areas of around Mt. Kenya, and parts of southeastern South Sudan.

According to the IRI/CPC sub-seasonal (sub-X) probability rainfall forecast, rainfall in the second half of April is likely to be average to above-average in parts of western Rwanda, Burundi, and southeastern South Sudan, and southwestern Ethiopia (Figure 5). Meanwhile, coastal Kenya, Somalia, Yemen, and northeastern Ethiopia are forecast to receive below-average rainfall, with the rest of the region expected to receive near-average rainfall.