The African Monsoon Recent Evolution and Current Status Include Week-1 and Week-2 Outlooks

1. The African Monsoon Recent Evolution and Current StatusInclude Week-1 and Week-2 Outlooks Update prepared by Climate Prediction Center / NCEP 11 April 2016 For more information, visit: http://www.cpc.ncep.noaa.gov/products/Global_Monsoons/African_Monsoons/precip_monitoring.shtml

2. Outline • Highlights • Recent Evolution and Current Conditions • NCEP GEFS Forecasts • Summary

3. Highlights:Last 7 Days • Weekly total rainfall exceeded 100 mm over portions of eastern Ethiopia, northern Malawi and southern Tanzania. • Week-1 outlooks call for an increased chance for below-average rainfall over southern DRC. In contrast, there is an increased chance for above-average rainfall over central and eastern Ethiopia, eastern Tanzania and northeastern Mozambique.

4. Rainfall Patterns: Last 7 Days During the past seven days, above-average rainfall was observed over local areas in Cote d’Ivoire much of Burkina Faso, Benin, much of Nigeria, northern Cameroon, Gabon, local areas in CAR, southeastern DRC, southern and eastern Ethiopia, Tanzania, northern Malawi, Zimbabwe, local areas in Mozambique, and portions of South Africa. In contrast, local areas in southeastern Nigeria and southern Cameroon, many parts of DRC, portions of South Sudan and western Ethiopia, Uganda, eastern Kenya, southern Somalia, Angola, western Zambia, and Madagascar had below-average rainfall.

5. Rainfall Patterns: Last 30 Days During the past 30 days, rainfall was below-average over portions of eastern Guinea, northern Cote d’Ivoire, local areas in southern Gabon, southern and eastern DRC, southern Congo-Brazzaville, much of Angola, portions of Namibia, Uganda, southeastern South Sudan, local areas in Ethiopia, Kenya, southern Somalia, local areas in Tanzania and northern Mozambique, parts of Zambia, and local areas in South Africa. In contrast, southern Cote d’Ivoire, Burkina Faso, Ghana, Togo, Benin, Nigeria, Cameroon, much of Gabon, Congo-Brazzaville, CAR, western South Sudan, central and northern DRC, northeastern Namibia, portions of Zambia, Botswana, Zimbabwe, portions of South Africa, Malawi, Tanzania, portions of Mozambique, and much of Madagascar had above-average rainfall.

6. Rainfall Patterns: Last 90 Days During the past 90 days, rainfall was above-average over eastern Mauritania, northern Mali, coastal Cote d’Ivoire, Burkina Faso, Togo, Benin, Nigeria, Cameroon, western Gabon, CAR, western South Sudan, eastern Ethiopia, northern DRC, local areas in Congo-Brazzaville, local areas in Kenya, much of Tanzania, eastern Namibia, much of Botswana, western Zambia, parts of South Africa, northern Mozambique, northern Malawi, and portions of Madagascar. In contrast, pats of eastern Guinea, Liberia, much of Cote d’Ivoire, southern Ghana, portions of Gabon, local areas in Congo-Brazzaville, southern and eastern DRC, many parts of Angola, portions of Namibia, Uganda, southeastern South Sudan and western Ethiopia, Kenya, southern Somalia, Uganda, portions of Zambia, local areas in southern Botswana, portions of South Africa, southern Malawi, central and southern Mozambique, and southern Madagascar had below-average rainfall.

7. Rainfall Patterns: Last 180 Days During the past 180 days, rainfall was above-average over parts of Mauritania, Senegal, Gambia, much of Guinea, Guinea-Bissau, eastern Liberia, Mali, Burkina Faso, Cote d’Ivoire, portions of Ghana, Togo, Benin, Nigeria, western Niger, southern Chad, CAR, local areas in Gabon, local areas in DRC, South Sudan Republic, southern Sudan, southern Somalia, much of Ethiopia, Kenya and Tanzania, coastal Angola, portions of western and northern Zambia, northern Botswana, northern Malawi, northern Mozambique, and parts of Madagascar. In contrast, local areas in Guinea, western Liberia, portions of Cote d’Ivoire, local areas in Ghana and Nigeria, parts of southern Cameroon, Equatorial Guinea, portions of Gabon, much of Angola and DRC, parts of central and northeastern Ethiopia, southern Zambia, portions of Namibia, parts of southern Botswana, Zimbabwe, southern Malawi, central and southern Mozambique, central and eastern South Africa, and local areas in Madagascar had below-average rainfall.

8. Recent Rainfall Evolution Daily evolution of rainfall over the last 90 days at selected locations show that moderate to locally heavy rainfall sustained moisture surpluses across parts of Tanzania (bottom right). Despite the recent rainfall increase across parts of West and East Africa, seasonal total rainfall remained below-average over parts of Ghana (bottom left) and eastern Ethiopia (top right).

9. Atmospheric Circulation:Last 7 Days The 700 hPa wind anomalies (left panel) featured an area of stronger than normal monsoon flow from the Indian Ocean and its associated convergence across the Greater Horn of Africa.

10. NCEP GEFS Model ForecastsNon-Bias Corrected Probability of precipitation exceedance Week-1: Valid 12 – 18 Apr, 2016 Week-2: Valid 19 – 25 Apr, 2016 For week-1 (left panel) and week-2 (right panel), there is an increased chance for rainfall to exceed 50 mm over portions of Cameroon and Gabon, northern Angola, parts of DRC, the Lake Victoria region, and portions of Ethiopia.

11. Week-1 Precipitation Outlooks 12 – 18 Apr, 2016 • There is an increased chance for below-average rainfall over Southern DRC: An area of lower-level divergence is expected to suppress rainfall in the region. Confidence: Moderate • There is an increased chance for above-average rainfall over portions of central and eastern Ethiopia, northwestern Somalia, and Djibouti: An area of stronger than normal monsoon flow from the Indian Ocean and anomalous lower-level convergence is expected to enhance rainfall in the region. Confidence: Moderate • There is an increased chance for above-average rainfall over eastern Tanzania and northeastern Mozambique: Anomalous onshore flow with its associated lower-level convergence is expected to enhance rainfall in the region. Confidence: Moderate

12. Week-2 Precipitation Outlooks 19 – 25 Apr, 2016 • There is an increased chance for above-average rainfall over portions of central and eastern Ethiopia: An area of stronger than normal monsoon flow from the Indian Ocean and anomalous lower-level convergence is expected to enhance rainfall in the region. Confidence: Moderate • There is an increased chance for below-average rainfall over portions of southern and eastern Kenya, and southern Somalia: Anomalous lower-level divergent flow is expected to suppress rainfall in the region. Confidence: Moderate

13. Summary • During the past seven days, above-average rainfall was observed over local areas in Cote d’Ivoire much of Burkina Faso, Benin, much of Nigeria, northern Cameroon, Gabon, local areas in CAR, southeastern DRC, southern and eastern Ethiopia, Tanzania, northern Malawi, Zimbabwe, local areas in Mozambique, and portions of South Africa. In contrast, local areas in southeastern Nigeria and southern Cameroon, many parts of DRC, portions of South Sudan and western Ethiopia, Uganda, eastern Kenya, southern Somalia, Angola, western Zambia, and Madagascar had below-average rainfall. • During the past 30 days, rainfall was below-average over portions of eastern Guinea, northern Cote d’Ivoire, local areas in southern Gabon, southern and eastern DRC, southern Congo-Brazzaville, much of Angola, portions of Namibia, Uganda, southeastern South Sudan, local areas in Ethiopia, Kenya, southern Somalia, local areas in Tanzania and northern Mozambique, parts of Zambia, and local areas in South Africa. In contrast, southern Cote d’Ivoire, Burkina Faso, Ghana, Togo, Benin, Nigeria, Cameroon, much of Gabon, Congo-Brazzaville, CAR, western South Sudan, central and northern DRC, northeastern Namibia, portions of Zambia, Botswana, Zimbabwe, portions of South Africa, Malawi, Tanzania, portions of Mozambique, and much of Madagascar had above-average rainfall. • During the past 90 days, rainfall was above-average over eastern Mauritania, northern Mali, coastal Cote d’Ivoire, Burkina Faso, Togo, Benin, Nigeria, Cameroon, western Gabon, CAR, western South Sudan, eastern Ethiopia, northern DRC, local areas in Congo-Brazzaville, local areas in Kenya, much of Tanzania, eastern Namibia, much of Botswana, western Zambia, parts of South Africa, northern Mozambique, northern Malawi, and portions of Madagascar. In contrast, pats of eastern Guinea, Liberia, much of Cote d’Ivoire, southern Ghana, portions of Gabon, local areas in Congo-Brazzaville, southern and eastern DRC, many parts of Angola, portions of Namibia, Uganda, southeastern South Sudan and western Ethiopia, Kenya, southern Somalia, Uganda, portions of Zambia, local areas in southern Botswana, portions of South Africa, southern Malawi, central and southern Mozambique, and southern Madagascar had below-average rainfall. • Week-1 outlooks call for an increased chance for below-average rainfall over southern DRC. In contrast, there is an increased chance for above-average rainfall over central and eastern Ethiopia, eastern Tanzania and northeastern Mozambique.