1. The African Monsoon Recent Evolution and Current Status Include Week-1 and Week-2 Outlooks Update prepared by Climate Prediction Center / NCEP 29 October 2012 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 Moderate to locally heavy rainfall resulted in moisture surpluses over portions of the Gulf of Guinea and Central African countries, and South Sudan. Week-1 outlooks call for an increased chance for above-average rainfall over eastern DRC, the Lake Victoria region, western Tanzania, and northern Zambia and Malawi. In contrast, there is an increased chance for below-average rainfall over portions of Nigeria, Cameroon, CAR, and northern DRC.

4. Rainfall Patterns: Last 7 Days During the past seven days, above-average rainfall was observed over portions of Sierra Leone, Liberia and Cote d’Ivoire, much of Ghana, local areas in Burkina Faso, Mali and Cameroon, Equatorial Guinea, local areas in Chad and Congo, portions of CAR, South Sudan, portions of DRC, Angola and Botswana, local areas in Zimbabwe and South Africa, portions of Madagascar, local areas in Kenya and Ethiopia. In contrast, portions of Cameroon, southern Gabon, Congo, local areas in Angola and Uganda, portions of Kenya, Somalia, and local areas in Ethiopia had below average rainfall.

5. Rainfall Patterns: Last 30 Days During the past 30 days, above-average rainfall was observed over portions of eastern Senegal and Mali, Guinea, Sierra Leone, Liberia, much of Cote D’Ivoire, Ghana, local areas in Burkina Faso, portions of Togo, Benin, much of Nigeria, Cameroon and Gabon, portions of CAR, Congo and Angola, portions of DRC, local areas in Ethiopia, southern Uganda, central Kenya and southern Somalia, portions of Zimbabwe, eastern Botswana, southern Mozambique, portions of South Africa and many parts of Madagascar. In contrast, local areas in Mali and Burkina Faso, central Benin, southern Chad, local areas in CAR and South Sudan, and portions of DRC, Somalia, local areas in South Africa, and much of Ethiopia had below average rainfall.

6. Rainfall Patterns: Last 90 Days During the past 90 days, southern Mauritania, portions of Senegal, much of Guinea, Guinea-Bissau, Sierra Leone, Mali and Burkina Faso, portions of Liberia, and eastern Nigeria, local areas in Niger, southern Chad, northern Cameroon, portions of CAR and DRC, South Sudan, local areas in Angola, northern Uganda, western Kenya, portions of Ethiopia and eastern South Africa had above average rainfall. In contrast, rainfall was below average over eastern Ghana, Togo, local areas in Nigeria, southern Cameroon, portions of DRC, northeastern Ethiopia and Eritrea.

7. Rainfall Patterns: Last 180 Days During the past 180 days, rainfall was above-average over local areas in Senegal, southern Mauritania, many parts of Mali, Guinea Bissau, Guinea, Sierra Leone, local areas in Cote d’Ivoire, Burkina Faso, local areas in Ghana and Benin, portions of Nigeria and Niger, southern Chad, northern Cameroon, portions of CAR, portions of Gabon and DRC, South Sudan, Uganda, western Kenya, local areas in Ethiopia and eastern South Africa. Eastern Liberia, southern Cote d’Ivoire, southern Benin, portions of Nigeria, southern Cameroon, Equatorial Guinea, northern Gabon, portions of Ethiopia and Eritrea had below average rainfall.

8. Recent Rainfall Evolution Daily evolution of rainfall over the last 90 days at selected stations reflects that rainfall remained above average despite the decreasing trend of rainfall over Gabon (bottom panel – left). Moderate to heavy rains continued to erode some of the rainfall deficits over Madagascar. Seasonal total rainfall remained below average due to the recent rainfall decrease over portions of western Ethiopia (top panel – right).

9. Atmospheric Circulation: Last 7 Days The 850hPa wind anomaly (left panel) featured anomalous northeasterly flow across portions of Central African region. Anomalous lower-level cyclonic shear was observed over Southeast Africa, and anomalous easterly flow prevailed over the Horn of Africa.

10. NCEP GEFS Model Forecasts Non-Bias Corrected Probability of precipitation exceedance Week-1: Valid 30 October – 05 November 2012 Week-2: Valid 06 – 12 November 2012 For week-1 (left panel), there is an increased chance for rainfall to exceed 50 mm across eastern DRC and the Lake Victoria region. For week-2 (right-panel), the higher probabilities of exceedence tend to increase over western Equatorial Africa, while slightly decreasing over the Lake Victoria region.

11. 30 October – 05 November 2012 Experimental Week-1 Precipitation Outlooks 1.There is an increased chance for below-average rainfall over eastern Nigeria, southern Chad, CAR and northern DRC: Anomalous westerly winds are expected to suppress rainfall in the region. Confidence: Moderate 2.There is an increased chance for above-average rainfall over eastern DRC, western Tanzania, Uganda, western Kenya, northern Zambia, and northern Malawi: Anomalous lower-level westerly flow from Congo combined with areas of lower level convergence are expected to enhance rainfall in the region. Confidence: Moderate

12. Experimental Week-2 Precipitation Outlooks 06 – 12 November 2012 1.There is an increased chance for below-average rainfall over southeastern Angola, and portions of Zambia, Zimbabwe, and Botswana: Anomalous low-level divergence is expected to suppress rainfall in the region. Confidence: Moderate

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