March to May rains started across a widespread portion of the region

• Widespread rains mark a near normal onset of both the February to May Belg rains in Ethiopia and the March to May long rains/Gu/Masika in much of the eastern Horn of Africa and the western parts of the region. Planting has already occurred in many areas.

• However, the rains have started late in eastern Amhara in Ethiopia and areas of Uganda along Lake Victoria.

• Moderate to heavy rains are forecast to continue into the next two weeks, but, will subside slightly during the second week. The rains are expected to be fully established and at their peak intensity in April.

Rainfall in late February and early March was mostly average to above average in amount (Figure 1). Rains started in February in Rwanda and Burundi and then spread into Uganda, southwestern Ethiopia, Kenya, and northern Tanzania in March. This is mostly normal timing for the start of the rains in the Belg-receiving areas in southwestern Ethiopia. It was also a mostly normal timing to the start of the rains for the Masika rains in northern Tanzania, the long rains in most of Kenya, and in the western parts of East Africa.

The rains started late in some areas. In others, they have been lighter than normal, and cumulative rainfall has been below average. The rains started up to twenty days late in some areas including some areas along Lake Victoria in Uganda and in eastern Amhara in Ethiopia. February and March rainfall was below average, up to 100 millimeters (mm) less than normal in North and South Wollo Zones in eastern Amhara Region in Ethiopia, in the Lake Victoria basin in Uganda, western Kenya, and northwestern Tanzania, and along the western parts of the Rwanda-Burundi border (Figure 1).

In most parts of the region, vegetation conditions have been fairly stable, and as measured by the eMODIS/Normalized Difference Vegetation Index (NDVI) anomaly, they have generally not yet started their seasonal improvement (Figure 2). Significantly below average vegetation conditions as measured by NDVI are found in much of Uganda, in the Lake Victoria basin in Kenya and Tanzania, northern Rwanda, coastal areas in southern Somalia, and Southern Nations, Nationalities, and Peoples’ Region in Ethiopia. The prolonged dry season and unseasonal hotter-than-normal land surface temperatures since January may have delayed land preparation and planting in some of these areas.

In the areas where the seasonal rains were a bit early and well established now, planting has occurred. Crops are currently in the emergence stage in areas of Rwanda, Burundi, Uganda, northern Tanzania, western Kenya, the central Rift Valley, and central Kenya. While land preparation and planting has begun, it is not yet complete in eastern Kenya, southern Somalia, and many of the Belg growing areas in Ethiopia.

Moderate to heavy rains are likely to continue over the coming week over most countries in the region. These rains will likely subside slightly and become less intense over the eastern Horn in early April as the tropical storm over the Mozambique Channel dissipates. There is a lower chance of rainfall over the coming week in Somalia, southeastern and western Ethiopia, and South Sudan (Figure 3). Sudan is generally dry at this time of year, and the forecast is for no rain in Sudan.

April is usually the month when the rains peak in intensity in the eastern Horn and in Uganda, Rwanda, Burundi, and western Tanzania. While generally helping promote pasture regeneration, cropping, and the replenishment water resources, the risk of flooding increases at this time. Currently, there is a moderate to high risk of floods in the Lake Victoria basin, near Mt. Elgon along the Kenya-Uganda border, and also along the Wabi Shabelle River in southern Somalia and Somali Region of Ethiopia due to the on-going rains. This risk is likely to increase as the rains intensify in April.

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