Delayed onset of the Deyr rains in most parts of Somalia in late October

The start of the Deyr rains has been delayed by one to three weeks across most of Somalia. Typically, the Deyr season begins in early October in northern and central regions and in mid-October in southern regions. According to preliminary Climate Hazards Group InfraRed Precipitation with Station data (CHIRPS) and confirmed by ground information, little to no precipitation occurred October 1^st through 20^th. Only parts of the Northwest and South received rainfall, which totaled less than 50 millimeters (mm) (Figure 1). Ground information, which was not confirmed by remote sensing imagery, also suggested that localized moderate rains fell in some central regions, specifically in pockets of Addun Pastoral, Hawd Pastoral, and Cowpea Agropastoral livelihood zones. Cumulative rainfall is 25-100 mm below the 1981-2010 average in most parts of the country, although cumulative rainfall across northern Somalia is climatologically average (Figure 2). As a result, there was no flood risk along the Shabelle and Juba river basins, and the Shabelle river levels declined.  

In the Northwest, moderate rainfall was reported across all livelihood zones in Awdal and Woqooyi Galbeed regions. This included parts of Guban Pastoral livelihood zone, which experienced unusual rainfall and flash floods originating in the Golis mountains. In Togdheer, moderate rains fell in all livelihood zones, with heavy rainfall reported in West Golis Pastoral livelihood zone in Sheikh district. Localized light to moderate rainfall also occurred in East Golis, Hawd Pastoral, and Northern Inland Pastoral (NIP) livelihood zones in Sool and Sanaag regions. Overall, the rains replenished pasture and water resources.   

In the Northeast, localized moderate rains fell in East Golis Pastoral livelihood zone in Aluula and Bossaso districts in Bari region and NIP livelihood zone in Bari’s Bossaso and Iskushuban districts. Dryness prevailed across the pastoral livelihood zones in Qardho, Bandarbeyla, and Qandala districts in Bari as well as Nugaal and northern Mudug regions. However, field reports indicated some rainfall fell in localized areas in Hawd Pastoral livelihood zone in Nugaal and northern Mudug.

In the central regions, localized moderate rains fell in Addun and Hawd Pastoral livelihood zones in Dhusamareb and Hobyo districts in Galgaduud and southern Mudug and in Cowpea Agropastoral livelihood zone in Harardhere district in southern Mudug. Apart from these areas, no precipitation occurred in the rest of Galgaduud and southern Mudug, including pastoral areas in Galkayo, Adado, Abudwaq, Elder and Elbur districts. 

In the South, there was little to no precipitation in most regions, including the key crop producing regions of Bay, Lower and Middle Shabelle, Hiiraan, and Lower and Middle Juba. Some localized light precipitation was reported in Beledweyne (Hiiraan), Southern Inland Pastoral  livelihood zone in Qoryoley (Lower Shabelle), pastoral areas in Elwak, Garboharey and Beledhawa (Gedo), agropastoral areas in Baidoa, Dinsor, and Qansahdhere (Bay), and pastoral areas in Hudur and Elbarde (Bakool). Rain gauge stations recorded 0-18 mm in Baidoa, Dinsor and Qansahdhere (Bay), 32-62 mm in Hudur and Elbarde (Bakool), 13 mm in Halgan (Hiiran), and 0mm in Sakow (Middle Juba). The Shabelle river water levels have started to considerably decline. At 2.12 meters, the current river level in Beledweyne is not adequate for irrigation.

The satellite-derived eMODIS Normalized Vegetation Index (NDVI) for October 11^th through 20^th shows generally average to above-average vegetation conditions due to the lasting impact of exceptional April to June 2018 Gu rainfall and typical August to September Karan rains (Figure 3). However, vegetation conditions remain below average in large parts of the Northeast due to poor Gu rainfall in that area and delayed start of the October Deyr season. The Climate Prediction Center’s seven-day forecast through October 31 predicts moderate to heavy rainfall ranging from 15 to 125 mm across most of the country, except in large parts of Bari region and localized areas in central and Lower Juba regions (Figure 4). According to the forecast, 60 to 125 mm of rainfall is also likely in the Ethiopian highlands, which would raise the river levels in both the Juba and Shabelle rivers and elevate the risk of flooding, at least in the upstream areas of Hiiraan region.

For more rain gauge data, please, contact So-Hydro@fao.org or visit www.faoswalim.org.