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 19 January 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 100mm over portions of Tanzania, northern Mozambique and northern Madagascar, whereas suppressed rainfall prevailed over central and southern Mozambique. • Week-1 outlooks call for an increased chance for above-average rainfall over eastern Namibia, western South Africa, southeastern DRC and portions of Tanzania. In contrast, there is an increased chance for below-average rainfall over parts of eastern Botswana, northeastern South Africa, southern Malawi, Zimbabwe, Mozambique, and southern Madagascar.

4. Rainfall Patterns: Last 7 Days During the past seven days, rainfall was above-average over local areas in Gabon, portions of eastern Angola and eastern Namibia, western Zambia, Botswana, portions of Zimbabwe and South Africa, much of Tanzania, southwestern Kenya, northern Mozambique and portions of Madagascar. In contrast, portions of southern Gabon, portions of Angola and Namibia, local areas in DRC, southern Malawi, central and southern Mozambique and western Madagascar had below-average rainfall.

5. Rainfall Patterns: Last 30 Days During the past 30 days, rainfall was below-average over Equatorial Guinea, much of Gabon, northern Congo-Brazzaville, northern DRC, parts of Uganda, southeastern Angola, local areas in Namibia, portions of Zambia, eastern Botswana, Zimbabwe, Malawi, portions of South Africa, central and southern Mozambique, and parts of western Madagascar. In contrast, local areas in Gabon, southern Congo-Brazzaville, southern and eastern DRC, many parts of Angola, Namibia, portions of northern Zambia, local areas in western Botswana, Kenya, Tanzania, portions of northern 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 portions of Mali, Senegal, Gambia, Guinea-Bissau, Guinea-Conakry, Sierra Leone, Liberia, much of Cote d’Ivoire, Ghana, Burkina Faso, local areas in southeastern Nigeria and southern Chad, western CAR, local areas in Gabon, much of South Sudan Republic, southern and eastern Sudan, portions of southern DRC, many parts of Ethiopia, Kenya, Uganda, much of Tanzania, Somalia, parts of Angola and western Namibia, portions of northern Zambia northern Mozambique, and much of Madagascar. In contrast, parts of Nigeria, portions of southern Cameroon, Equatorial Guinea, portions of Gabon, central and northern DRC, eastern CAR, many parts of Angola, eastern Namibia, Botswana, southern Zambia, much of Zimbabwe, Malawi, Mozambique, South Africa and local areas in western Madagascar received below-average rainfall.

7. Rainfall Patterns: Last 180 Days During the past 180 days, rainfall was above-average over many parts of Mauritania, Senegal, Gambia, much of Guinea, Guinea-Bissau, Sierra Leone, Liberia, Mali, Burkina Faso, portions of Cote d’Ivoire and northern Nigeria, parts of Niger and Chad, portions of CAR and Gabon, local areas in Congo-Brazzaville, portions of southern DRC, South Sudan Republic, southern and eastern Sudan, southern Somalia, much of Ethiopia, Kenya and Tanzania, local areas in southwestern Angola, western Namibia, portions of northern Zambia, northern Mozambique, coastal South Africa, and much of Madagascar. In contrast, local areas in Cote d’Ivoire, portions of Ghana, southern Togo, southern Benin, much of Nigeria, parts of Cameroon, Equatorial Guinea, much of Angola and DRC, parts of northeastern Ethiopia, southern Zambia, eastern Namibia, Botswana, Zimbabwe, Mozambique, and much of South Africa, and parts of western 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 helped to erode some of the accumulated rainfall deficits over parts of Angola (bottom left), whereas seasonal total rainfall remained below-average over much of Zimbabwe (bottom right). In contrast, seasonal total rainfall remained above-average over portions of Tanzania (top right).

9. Atmospheric Circulation:Last 7 Days The 850 hPa wind anomalies (left panel) featured lower-level cyclonic flow across southern Africa, and anomalous onshore flow across Southeastern Africa, which may have contributed to the observed above-average rainfall in the regions.

10. NCEP GEFS Model ForecastsNon-Bias Corrected Probability of precipitation exceedance Week-1: Valid 20 – 26 Jan, 2016 Week-2: Valid 27 Jan – 02 Feb, 2016 For week-1 (left panel), there is an increased chance for rainfall to exceed 50 mm over eastern Angola, eastern Namibia, southeastern DRC, northern Zambia, northern Malawi, eastern and southern Tanzania, local areas in South Africa and northern Madagascar. For week-2 (right panel), there is an increased chance for rainfall to exceed 50mm over portions of Angola, Zambia, northern Malawi, southern Tanzania, and local areas in northern Mozambique and northern Madagascar.

11. Week-1 Precipitation Outlooks 20 – 26 Jan, 2016 • There is an increased chance for above-average rainfall across eastern Namibia and western South Africa: Interactions between mid-latitude and tropical systems across Southern Africa is expected to enhance rainfall in the region. Confidence: Moderate • There is an increased chance for below-average rainfall over parts of eastern Botswana, northeastern South Africa, southern Malawi, Zimbabwe, Mozambique, and southern Madagascar: A broad area of lower-level divergence and upper-level convergence is expected to suppress rainfall in the region. Confidence: Moderate • There is an increased chance for above-average rainfall over portions of southeastern DRC and Tanzania: Anomalous westerly flow from the Congo Basin combined with anomalous upper-level divergence is expected to enhance rainfall in the region. Confidence: Moderate

12. Week-2 Precipitation Outlooks 27 Jan – 02 Feb, 2016 • There is an increased chance for below-average rainfall over portions of southern Zambia, Zimbabwe, southern Malawi, Mozambique, and Madagascar: A broad area of anomalous lower level divergence, coupled with upper-level convergence is expected to suppress rainfall in the region. Confidence: Moderate • There is an increased chance for above-average rainfall over southern Tanzania: An area of anomalous lower-level convergence and upper-level divergence is expected to enhance rainfall in the region. Confidence: Moderate

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