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 February 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 • Rainfall was below-average over parts of Angola and Namibia, and much of Tanzania. • Above-average rainfall was observed across portions of Botswana, Zimbabwe, southern Mozambique and South Africa. • Week-1 outlooks call for an increased chance for above-average rainfall across northern Angola, southern DRC, northern Zambia, Malawi, southern Tanzania, northern Mozambique, and the Lake Victoria region. There is an increased chance for below-average rainfall over parts southern Angola, southern Zambia, Namibia, Botswana, South Africa, Zimbabwe, and Mozambique.

4. Rainfall Patterns: Last 7 Days Weekly rainfall totals exceeded 100mm across parts of southwestern Zambia and northern Botswana, portions of Zimbabwe, and local areas in Mozambique. Rainfall was below-average across portions of the Gulf of Guinea region, southern Congo-Brazzaville, parts of Angola and Namibia, much of Tanzania, northern Mozambique, and parts of Madagascar. Southern Zambia, Botswana, much of Zimbabwe, western and southern Mozambique, many parts of South Africa and local areas in Madagascar had above-average rainfall.

5. Rainfall Patterns: Last 30 Days During the past 30 days, rainfall was above-average along the Gulf of Guinea coast, southern CAR, northeastern Ethiopia, northern Congo-Brazzaville, many parts of DRC, local areas in Angola, parts of Tanzania, eastern Zambia, parts of Botswana, southern Zimbabwe, many parts of South Africa, northern Malawi, and portions of Mozambique and the far northern Madagascar. Below-average rainfall was observed over Equatorial Guinea, Gabon local areas in DRC, southwestern Ethiopia, many parts of Uganda, southwestern Kenya, parts of Tanzania, portions of Angola, Namibia, western Zambia, 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, local areas in Nigeria and Cameroon, southern Central African Republic, much of Congo-Brazzaville, many parts of DRC, local areas in Ethiopia, Somalia and Kenya, much of Tanzania, parts of Angola, eastern Zambia, Malawi, many parts of Mozambique, Botswana, portions of Zimbabwe and South Africa, and northern Madagascar had above-average rainfall. Rainfall was below-average over parts of Liberia and Ghana, Togo, local areas in Nigeria, parts of Cameroon, Equatorial Guinea, Gabon, western CAR, portions of DRC, parts of Ethiopia and Uganda, parts of Somalia and Kenya. Below-average rainfall was also observed over many parts of Angola, Namibia, western Zambia, northern 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, many parts of Chad, portions of 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, 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, many parts of South Sudan, southern 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). Light to Moderate rainfall sustained moisture surpluses over parts of Mozambique (top right).

9. Atmospheric Circulation:Last 7 Days An area of anomalous lower-level wind convergence was evident across southeastern Africa.

10. NCEP GEFS Model ForecastsNon-Bias Corrected Probability of precipitation exceedance Week-1: Valid 20 – 26 February, 2019 Week-2: Valid February 27 – March 5, 2019 For week-1 (left panel) , there is an increased chance for weekly rainfall totals to exceed 50 mm over local areas in Ethiopia and Uganda, eastern and southern DRC, southern Tanzania, eastern Zambia, northern Mozambique and local areas in Madagascar. For week-2 (right panel), there is an increased chance for weekly rainfall totals to exceed 50 mm over parts of Gabon, portions of Angola and DRC, local areas in Uganda and Tanzania, northern Mozambique and Madagascar.

11. Week-1 Precipitation Outlooks 20 - 26 February, 2019 • There is an increased chance for above-average rainfall throughout northern Angola, southern DRC, northern Zambia, Malawi, southern Tanzania, and northern Mozambique: 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 below-average rainfall over parts southern Angola, southern Zambia, Namibia, Botswana, South Africa, Zimbabwe, and Mozambique: A broad area of anomalous upper-level convergence, coupled with pockets of lower-level divergence is expected to suppress rainfall in the region. Confidence: Moderate • There is an increased chance for above-average rainfall over the Lake Victoria region of Uganda, Rwanda, Tanzania, and Kenya: An area of anomalous lower-level convergence and upper-level divergence is expected to enhance rainfall in the region. Confidence: Moderate

12. Week-2 Precipitation Outlooks February 27 – March 5, 2019 • There is an increased chance for above-average rainfall throughout parts of Gabon, Congo, DRC, northern Angola, and northern Zambia: A broad 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 below-average rainfall across parts of southern Angola, northern Namibia, southern Zambia, northern Botswana, and western Zimbabwe: An area of anomalous lower-level divergence and upper-level convergence is expected to suppress rainfall in the region. Confidence: Moderate

13. Summary • Weekly rainfall totals exceeded 100mm across parts of southwestern Zambia and northern Botswana, portions of Zimbabwe, and local areas in Mozambique. Rainfall was below-average across portions of the Gulf of Guinea region, southern Congo-Brazzaville, parts of Angola and Namibia, much of Tanzania, northern Mozambique, and parts of Madagascar. Southern Zambia, Botswana, much of Zimbabwe, western and southern Mozambique, many parts of South Africa and local areas in Madagascar had above-average rainfall. • During the past 30 days, rainfall was above-average along the Gulf of Guinea coast, southern CAR, northeastern Ethiopia, northern Congo-Brazzaville, many parts of DRC, local areas in Angola, parts of Tanzania, eastern Zambia, parts of Botswana, southern Zimbabwe, many parts of South Africa, northern Malawi, and portions of Mozambique and the far northern Madagascar. Below-average rainfall was observed over Equatorial Guinea, Gabon local areas in DRC, southwestern Ethiopia, many parts of Uganda, southwestern Kenya, parts of Tanzania, portions of Angola, Namibia, western Zambia, 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, local areas in Nigeria and Cameroon, southern Central African Republic, much of Congo-Brazzaville, many parts of DRC, local areas in Ethiopia, Somalia and Kenya, much of Tanzania, parts of Angola, eastern Zambia, Malawi, many parts of Mozambique, Botswana, portions of Zimbabwe and South Africa, and northern Madagascar had above-average rainfall. Rainfall was below-average over parts of Liberia and Ghana, Togo, local areas in Nigeria, parts of Cameroon, Equatorial Guinea, Gabon, western CAR, portions of DRC, parts of Ethiopia and Uganda, parts of Somalia and Kenya. Below-average rainfall was also observed over many parts of Angola, Namibia, western Zambia, northern Zimbabwe, parts of Botswana and South Africa, and portions of Madagascar. • Week-1 outlooks call for an increased chance for above-average rainfall across northern Angola, southern DRC, northern Zambia, Malawi, southern Tanzania, northern Mozambique, and the Lake Victoria region. There is an increased chance for below-average rainfall over parts southern Angola, southern Zambia, Namibia, Botswana, South Africa, Zimbabwe, and Mozambique.