Early onset of the Deyr marked by above-average rainfall and high flood risk along Juba and Shabelle rivers

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Mogadishu, Somalia – The Deyr 2019 season began 10-20 days early in many areas of southern, central, and northwestern Somalia, but has not yet been fully established in the Northeast. According to preliminary Climate Hazards Group InfraRed Precipitation with Station data (CHIRPS) and confirmed by ground information, most of the South and Northwest received 100-175 millimeters (mm) of rainfall, while central and northeastern regions received 50-150 mm and 10-50 mm, respectively (Figure 1). In Bay and Bakool and in localized areas of Gedo, Shabelle, Woqooyi Galbeed, Togdheer, and Sanaag, rainfall exceeded 200 mm. Cumulative September-October rainfall ranges from 10 mm to more 100 mm above the 1981-2010 average across most of the country (Figure 2). As a result of precipitation within Somalia and excessive rainfall in river catchments of the Ethiopian highlands, the Juba and Shabelle rivers are near bankfull levels with an elevated risk of flooding. In parts of Gedo and the Shabelle and Juba regions, river breakages have already resulted in localized flooding.

FIGURE 1
Estimated rainfall (CHIRPS prelim) in mm, September 1-October 20, 2019
Source: FEWS NET/USGS

Situation

In the Northwest, the Deyr rains began in September and early October. Most livelihood zones in Awdal and Woqooyi Galbeed, including large parts of Guban Pastoral, received evenly distributed, moderate to heavy rains in the first 10 days of October and localized light to moderate rains in the October 10-20 period. Livelihood zones in Togdheer, Sool, and Sanaag regions experienced intermittent and localized low to moderate rains. This precipitation has been adequate to improve rangeland conditions, provide migration options from dry areas, and improve livestock body conditions, market value, milk productivity, and reproductivity.  

In the Northeast, the Deyr rains have yet to start in most livelihood zones. In Bari, little to no rainfall has been reported in most of Northern Inland Pastoral, Coastal Deeh Pastoral and Fishing, and East Golis Pastoral livelihood zones. However, localized light to moderate rains were observed in West Golis Pastoral areas of Bossaso and Qandala districts of Bari in the October 11-20 period. Similar trends were observed in pastoral areas of Nugaal and northern Mudug, where little to no precipitation was received except for localized showers in parts of western Addun Pastoral and Hawd Pastoral livelihood zones.

FIGURE 2 Estimated rainfall anomaly (CHIRPS prelim) in mm compared to 1981-2010 average, September 1-October 20, 2019 Source: FEWS NET/USGS

In the central regions, the onset of Deyr precipitation occurred in early October. Moderate to heavy rains were reported in most livelihood zones of Galgaduud and southern Mudug during the October 1-20 period. Although field information indicates there are pockets in all livelihood zones where precipitation is still below normal, the October rains have broken the drought cycle by improving access to pasture and water resources and reducing water trucking and atypical livestock migration. The rains also allowed for cowpea crop planting and germination in Cowpea Belt Agropastoral livelihood zone.

In the South, the Deyr rains began at the end of September in some areas and spread to the rest of the region in the first three weeks of October. In the October 10-20 period, widespread moderate to heavy rains fell in most agropastoral, pastoral, and riverine livelihood zones of Bay, Bakool, Hiiraan, Gedo, Lower and Middle Shabelle, and Lower and Middle Juba. Rain gauge stations recorded 186.5 mm in Baidoa (Bay), 170 mm in Dinsor (Bay), 198 mm in Hudur (Bakool), 125.5 mm in Beletweyne (Hiiraan), 107 mm in Afgoye (Shabelle), and 200 mm in Sakow (Juba). Although localized in some areas, including Coastal Deeh Pastoral of Adale district (Middle Juba), the rains have largely been beneficial to cropping activities, rangeland regeneration, and livestock productivity and reproductivity. However, heavy rains led to flash floods in localized areas of Bay, Gedo, and Juba regions, which destroyed germinated crops, cut off road networks, and killed livestock. Due to local rainfall as well as excessive precipitation in the Ethiopian highlands, the water levels of both the Juba and Shabelle rivers are approaching bankfull and the risk of flooding is high. Localized, but contained, flooding has been reported in parts of Beletewyne (Hiiraan), Mahadday/Jowhar (Middle Shabelle), Bardhere, Luuq and Beledhawa (Gedo), and Juba, where flooding occurred in low-lying deshek areas (natural depressions in the flood plain used for recessional agriculture).  

FIGURE 3
Figure 3. eMODIS Normalized Difference Vegetation Index anomaly from the 2003-2017 median, October 11-20, 2019
Source: FEWS NET/USGS
FIGURE 4
Global Forecast System (GFS) rainfall forecast in mm for October 24-29, 2019
Source: NOAA/CPC

The satellite-derived eMODIS Normalized Vegetation Index (NDVI) for the October 11-20  period shows below-normal to normal vegetation conditions across most of the country. Above-normal conditions are visible in large parts of the Northwest and localized areas in the South (Figure 3). However, due to the moderate-to-heavy rainfall recorded in southern and central regions during mid-October, improved vegetation conditions are likely within the coming weeks. The NOAA Climate Prediction Center’s forecast through October 29 predicts moderate to heavy rainfall ranging from 15 to 100 mm across most of the South and localized areas of central Somalia. Dry conditions are expected in most other central and northern regions of the country (Figure 4).

 

 

 

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