African Monsoon: Recent Evolution & Outlook Update

1. The African Monsoon Recent Evolution and Current StatusInclude Week-1 and Week-2 Outlooks Update prepared by Climate Prediction Center / NCEP 4 March 2019 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 rainfall totals exceeded 100mm over parts of northern Madagascar. • Suppressed rainfall prevailed over many places in Southern Africa. • Week-1 outlooks call for an increased chance for below-average rainfall over much of CAR, western South Sudan, northern DRC, central and eastern Angola, eastern Namibia, western Zambia, Botswana and western Zimbabwe. In contrast, there is an increased chance for above-average rainfall over eastern Zambia, Malawi, Tanzania, northern Mozambique, and central and northern Madagascar.

4. Rainfall Patterns: Last 7 Days Weekly rainfall totals exceeded 100mm over parts of northern Madagascar. Rainfall was above-average over parts of parts of Nigeria, CAR, local areas in Ethiopia, parts of DRC, central and southern Tanzania, parts of northern Zambia and northern Mozambique, and northeastern Madagascar. Many parts of Liberia, Cote d’Ivoire, Ghana, Gabon, southern Congo-Brazzaville, much of Angola, Namibia, Botswana, South Africa, many parts of Zambia, Zimbabwe, Malawi, Mozambique, and many parts of Madagascar had below-average rainfall.

5. Rainfall Patterns: Last 30 Days During the past 30 days, rainfall was above-average parts of Cote d’Ivoire, southern Nigeria, Cameroon, much of CAR, parts of South Sudan, northeastern and southwestern Ethiopia, local areas in Gabon, northern Congo-Brazzaville, many parts of DRC, local areas in Angola, many parts of Tanzania, eastern Zambia, parts of Botswana and Zimbabwe, many parts of South Africa, Malawi, portions of Mozambique, and the far northern Madagascar. Below-average rainfall was observed over Equatorial Guinea, portions of Gabon and Congo-Brazzaville, parts of Ethiopia and Kenya, parts of northern Tanzania, much of Angola, Namibia, western Zambia, southern Malawi, northern Zimbabwe, central Mozambique, and many parts of Madagascar.

6. Rainfall Patterns: Last 90 Days During the past 90 days, portions of Côte d’Ivoire, local areas in Ghana and Benin, southern Nigeria, northern Cameroon, much of Central African Republic, much of Congo-Brazzaville, many parts of DRC, local areas in Ethiopia, and Kenya, much of Tanzania, local areas in Angola, eastern and northern Zambia, Malawi, many parts of Mozambique, Botswana, local areas in Zimbabwe, parts of South Africa, and northern and southern Madagascar had above-average rainfall. Rainfall was below-average over parts of Sierra Leone, Liberia, Ghana and Togo, local areas in Nigeria, southern Cameroon, Equatorial Guinea, much of Gabon, portions of DRC, parts of Ethiopia and Kenya. Below-average rainfall was also observed over many parts of Angola, Namibia, western Zambia, Zimbabwe, parts of Botswana and South Africa, and portions of Madagascar.

7. Rainfall Patterns: Last 180 Days During the past 180 days, rainfall was above-average over many parts of Mauritania, much of Senegal, The Gambia, Guinea-Bissau, Guinea-Conakry, Mali, Sierra Leone, Liberia, much of Cote d’Ivoire and Burkina Faso, Ghana, Togo, Benin, portions of Nigeria and Cameroon, Niger, parts of Chad and CAR, Sudan, local areas in South Sudan, Eritrea, portions of Ethiopia, many parts of Tanzania, much of Congo-Brazzaville, many parts of DRC, northwestern Angola, local areas in Botswana and South Africa, eastern Zambia, Malawi, much of Mozambique, and portions of Madagascar. Below-average rainfall was observed over parts of Nigeria and Cameroon, Equatorial Guinea, Gabon, parts of southern Chad, portions of CAR, parts of DRC, parts of South Sudan, portions of Ethiopia, Somalia, local areas in Uganda, Kenya, local areas in Tanzania, many parts of Angola and Namibia, western Zambia, parts of Botswana, Zimbabwe, many parts of South Africa, and portions of Madagascar.

8. Recent Rainfall Evolution Daily evolution of rainfall over the last 90 days at selected locations shows that seasonal total rainfall remained below-average over southern Angola (left panel) and western Zambia (bottom left). Moderate to heavy rainfall sustained moisture surpluses over parts of northern Malawi (top right).

9. Atmospheric Circulation:Last 7 Days An area of anomalous upper-level wind convergence is evident across Southern Africa (right panel).

10. NCEP GEFS Model ForecastsNon-Bias Corrected Probability of precipitation exceedance Week-1: Valid 5 – 11 March, 2019 Week-2: Valid 12 – 18 March, 2019 For week-1 (left panel) , there is an increased chance for weekly rainfall totals to exceed 50 mm over parts of western Angola, southern and eastern DRC, eastern Zambia, parts of Ethiopia and Tanzania, Malawi, northern Mozambique, and central and northern Madagascar. For week-2 (right panel), there is an increased chance for weekly rainfall totals to exceed 50 mm over local areas in Gabon and Angola, parts of southern and eastern DRC, portions of Tanzania, northern Malawi, and northern Madagascar.

11. Week-1 Precipitation Outlooks 5 – 11 March, 2019 • There is an increased chance for below-average rainfall across much of CAR, western South Sudan and northern DRC: An area of anomalous lower-level divergence is expected to suppress rainfall in the region. Confidence: Moderate • There is an increased chance for below-average rainfall over central and eastern Angola, eastern Namibia, western Zambia, Botswana and western Zimbabwe: An area of anomalous lower-lever 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 eastern Zambia, Malawi, Tanzania, northern Mozambique, Comoros, and central and northern Madagascar: An area of anomalous lower-level cyclonic flow and upper-level divergence, combined with the projected phase of the MJO is expected to enhance rainfall in the region. Confidence: High

12. Week-2 Precipitation Outlooks 12 – 18 March, 2019 • There is an increased chance for below-average rainfall over much of CAR, parts of northern Congo-Brazzaville, northern DRC and western South Sudan: An area of anomalous lower-level divergence and upper-level convergence is expected to enhance rainfall in the region. Confidence: Moderate • There is an increased chance for below-average rainfall over eastern Angola, northeastern Namibia, western and southern Zambia, northern Namibia, Zimbabwe and parts of western Mozambique: An area of anomalous lower-lever 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 parts of eastern DRC, Burundi, Tanzania, and parts of northeastern Zambia: An area of anomalous lower-level convergence and upper-level divergence is expected to enhance rainfall in the region. Confidence: Moderate • There is an increased chance for above-average rainfall over northern Madagascar: An area of anomalous lower-level cyclonic flow and upper-level divergence is expected to enhance rainfall in the region. Confidence: Moderate

13. Summary • Weekly rainfall totals exceeded 100mm over parts of northern Madagascar. Rainfall was above-average over parts of parts of Nigeria, CAR, local areas in Ethiopia, parts of DRC, central and southern Tanzania, parts of northern Zambia and northern Mozambique, and northeastern Madagascar. Many parts of Liberia, Cote d’Ivoire, Ghana, Gabon, southern Congo-Brazzaville, much of Angola, Namibia, Botswana, South Africa, many parts of Zambia, Zimbabwe, Malawi, Mozambique, and many parts of Madagascar had below-average rainfall. • During the past 30 days, rainfall was above-average parts of Cote d’Ivoire, southern Nigeria, Cameroon, much of CAR, parts of South Sudan, northeastern and southwestern Ethiopia, local areas in Gabon, northern Congo-Brazzaville, many parts of DRC, local areas in Angola, many parts of Tanzania, eastern Zambia, parts of Botswana and Zimbabwe, many parts of South Africa, Malawi, portions of Mozambique, and the far northern Madagascar. Below-average rainfall was observed over Equatorial Guinea, portions of Gabon and Congo-Brazzaville, parts of Ethiopia and Kenya, parts of northern Tanzania, much of Angola, Namibia, western Zambia, southern Malawi, northern Zimbabwe, central Mozambique, and many parts of Madagascar. • During the past 90 days, portions of Côte d’Ivoire, local areas in Ghana and Benin, southern Nigeria, northern Cameroon, much of Central African Republic, much of Congo-Brazzaville, many parts of DRC, local areas in Ethiopia, and Kenya, much of Tanzania, local areas in Angola, eastern and northern Zambia, Malawi, many parts of Mozambique, Botswana, local areas in Zimbabwe, parts of South Africa, and northern and southern Madagascar had above-average rainfall. Rainfall was below-average over parts of Sierra Leone, Liberia, Ghana and Togo, local areas in Nigeria, southern Cameroon, Equatorial Guinea, much of Gabon, portions of DRC, parts of Ethiopia and Kenya. Below-average rainfall was also observed over many parts of Angola, Namibia, western Zambia, Zimbabwe, parts of Botswana and South Africa, and portions of Madagascar. • Week-1 outlooks call for an increased chance for below-average rainfall over much of CAR, western South Sudan, northern DRC, central and eastern Angola, eastern Namibia, western Zambia, Botswana and western Zimbabwe. In contrast, there is an increased chance for above-average rainfall over eastern Zambia, Malawi, Tanzania, northern Mozambique, and central and northern Madagascar.