The multi-agency Flood Task Force (FTF) issued an Alert for Unseasonal Rainfall and Flood in October 2015 to raise awareness of anticipated flood risk in Wabe Shebelle, Genale/Dawa, and southeastern parts of the country.
The DRMFSS-led FTF prepared this flood Contingency Plan (CP) in order to mitigate the adverse impacts of flooding. The CP identifies the most likely scenario based on the weather forecast and analysis of the preparedness and response capacity for the flood anticipated areas. The NMA forecast for bega, which formed the basis for the development of the Alert and this CP, warns that flooding is anticipated in the southern and provides flood-related requirements by sector for the bega (October 2015 to January 2016) period, including other mitigation and preparedness efforts.
Since the beginning of bega season, incidents of flooding were reported in East Imey, Mustahil and Kelafo woredas of Shebelle zone in Somali region due to the overflow of the Wabe Shebelle River (East Imey) and flash flood. Evacuation of at-risk population to safer/higher grounds was undertaken in Mustahil and Kelafo woredas.
1.2 El Niño
According to NMA 2015 bega weather outlook, there is a high probability of El Niño to cause above-normal rainfall in the October to January 2016 period leading to flooding in the south and south eastern parts of the country. The El Niño effect is anticipated to persist until January 2016. This indicates the prevalence of dry conditions, unseasonal rainfall and normal to above-normal rainfall as indicated in the forecast below.
1.3 Forecast for bega 2015
The NMA identified the years 1982/83 and 1997/98 as El Niño analogue years. The outlook also indicates that the season (October 2015 to January 2016) will be characterized by effects of El Niño global episodes. This phenomenon is expected to result in following.
• Above-normal rainfall performance is anticipated to dominate across the south and southeastern parts of the country. Heavy fall is likely to prevail over some pocket areas.
• Unseasonal (above-normal) rainfall is expected in the northern, northeastern, eastern and central parts of Ethiopia.
• Normal rainfall is anticipated predominantly in southwestern and western parts of the country.
• Normal to above-normal rainfall is likely in northwestern parts of the country.
• The chance for the prevalence of frost in the highland areas is minimal.
Despite overall dry weather conditions, above normal to above normal rainfall is anticipated in central, eastern and southern Tigray of Tigray, Awi zone, Bahdar Zuria, west and east Gojjam, some parts of north and south Gondar, Wag Hamera, Oromia, north and south Wello, north Shewa of Amhara, Illubabur, Jimma, west and east Wellega, Horo Gudru, west shewa, Arsi, Bale, Borena and Guji zones of Oromia, kefa, Bench Maji, Wolayita, Gurage, Hadiya, some parts of Sidama, Gamogofa and Segen Peoples zones of SNNPR and most parts of Somali Regions during the 2nd dekad of November 2015.
In general according to the NMA decadal forecast ( 2rd dekad of November 2015), the expected heavy rainfall will likely cause flash floods in some parts of SNNP, Southern Oromia and Somali Regions.