The African Monsoon Recent Evolution and Current Status Include Week-1 and Week-2 Outlooks Update prepared by Climate Prediction Center / NCEP 12 January 2015 For more information, visit:

Outline Highlights Recent Evolution and Current Conditions NCEP GEFS Forecasts Summary

Highlights: Last 7 Days Weekly total rainfall surpluses exceeded 100mm over portions of Mozambique, southeastern Tanzania and western Madagascar. Suppressed rainfall continued to prevail over much of the Central and Southern Africa countries. Week-1 outlooks call for an increased chance for below-average rainfall over Equatorial Guinea, Gabon, Congo-Brazzaville, much of DRC, northern Angola, Botswana and Zimbabwe. In contrast, there is an increased chance for above-average rainfall over eastern Zambia, much of Malawi, southern Tanzania, Mozambique and Madagascar.

Rainfall Patterns: Last 7 Days During the past seven days, below-average rainfall was observed over Equatorial Guinea, Gabon, Congo-Brazzaville, much of DRC, Angola, Uganda, Rwanda, Burundi, western Tanzania, northern Namibia, Botswana, Zimbabwe, South Africa and southern Mozambique. In contrast, local areas in DRC and Angola, eastern Zambia, Malawi, portions of southern Tanzania, northern Mozambique and Madagascar had above-average rainfall.

Rainfall Patterns: Last 30 Days During the past 30 days, rainfall was below-average over portions of southern Cameroon and CAR, much of Equatorial Guinea, Gabon, Congo-Brazzaville, DRC, Angola, Namibia, Uganda, southwestern Ethiopia, Kenya, and portions of Tanzania and South Africa. In contrast, local areas in Gabon, northern DRC and Tanzania, southern Zambia, eastern Botswana, much of Zimbabwe, Malawi, much of Mozambique, local areas in Tanzania and South Africa, and much of Madagascar had above-average rainfall.

Rainfall Patterns: Last 90 Days During the past 90 days, Liberia, southern CAR, local areas in northern DRC, western Gabon, portions of South Sudan Republic, local areas in Tanzania, eastern Zimbabwe, central and southern Mozambique, southern Malawi, local areas in northern Botswana, and portions of eastern Madagascar had above-average rainfall. Below-average rainfall was observed over portions of Equatorial Guinea, southern Congo-Brazzaville, portions of Kenya, southern Somalia, Angola, Central and Southern DRC, Zambia, northern Malawi, and eastern South Africa.

Rainfall Patterns: Last 180 Days During the past 180 days, rainfall was above-average over portions of Guinea-Conakry, Liberia, western Cote d’Ivoire, portions of Mali, western Burkina Faso, Gabon, portions of South Sudan Republic, Ethiopia, Eritrea, southern and eastern Sudan, portions of the Lake Victoria region, eastern Zimbabwe, central Mozambique and local areas in Madagascar. In contrast, much of Nigeria, Cameroon, Equatorial Guinea, southern Congo-Brazzaville, northern Gabon, Angola, southern DRC, northern Zambia, and local areas in Madagascar and eastern South Africa had below-average rainfall.

Recent Rainfall Evolution Daily evolution of rainfall over the last 90 days at selected places reflects that seasonal total rainfall remained below-average over parts of Angola (bottom left) and eastern Zambia (top-right). Moderate to heavy rainfall helped to offset accumulated rainfall deficits over parts of northern Mozambique (bottom-tight).

Atmospheric Circulation: Last 7 Days The 850hpa wind anomalies (left panel) featured lower-level cyclonic circulation across southeastern Africa, which may have contributed to the observed heavy rainfall in the region.

NCEP GEFS Model Forecasts Non-Bias Corrected Probability of precipitation exceedance Week-1: Valid 13 – 19 January 2015 Week-2: Valid 20 – 26 January 2015 For week-1 (left panel) and week-2 (right panel) there is an increased chance for rainfall to exceed 50 mm over portions of Angola, Zambia, Malawi, northern Mozambique and Madagascar.

Week-1 Precipitation Outlooks 13 Jan – 19 Jan There is an increased chance for below-average rainfall over Equatorial Guinea, eastern Gabon, Congo- Brazzaville and northern DRC: Anomalous lower-level divergence combined with anomalous upper-level convergence is expected to suppress rainfall in the region. Confidence: Moderate 2.There is an increased chance for below-average rainfall over eastern Botswana, southern Zimbabwe, and northern South Africa: Anomalous lower-level divergence, combined with upper-level convergence is expected to suppress rainfall in the region. Confidence: Moderate 3.There is an increased chance for above-average rainfall over northern Mozambique, southern Malawi, and much of Madagascar: A broad area of anomalous lower-level lower level cyclonic circulation combined with upper-level divergence is expected to enhance rainfall in the region. Confidence: Moderate 4.There is an increased chance for above-average rainfall across the Mozambique Channel and the neighboring places of Mozambique and Madagascar: Potential tropical cyclone development in the Mozambique Channel is expected to enhance rainfall in the region.

Week-2 Precipitation Outlooks 20 Jan – 26 Jan There is an increased chance for below-average rainfall over portions of Congo-Brazzaville and northern DRC: Anomalous lower-level divergence combined with upper-level convergence is expected to suppress rainfall in the region. Confidence: Moderate 2.There is an increased chance for above-average rainfall over southern Angola and western Zambia: Anomalous lower-level convergence combined with upper-level divergence is expected to enhance rainfall in the region. Confidence: Moderate 3.There is an increased chance for below-average rainfall over eastern Botswana, Zimbabwe, and parts of western Mozambique: Anomalous lower-level divergence combined with anomalous upper level convergence is expected to suppress rainfall in the region. Confidence: Moderate

Summary During the past seven days, below-average rainfall was observed over Equatorial Guinea, Gabon, Congo-Brazzaville, much of DRC, Angola, Uganda, Rwanda, Burundi, western Tanzania, northern Namibia, Botswana, Zimbabwe, South Africa and southern Mozambique. In contrast, local areas in DRC and Angola, eastern Zambia, Malawi, portions of southern Tanzania, northern Mozambique and Madagascar had above-average rainfall. During the past 30 days, rainfall was below-average over portions of southern Cameroon and CAR, much of Equatorial Guinea, Gabon, Congo-Brazzaville, DRC, Angola, Namibia, Uganda, southwestern Ethiopia, Kenya, and portions of Tanzania and South Africa. In contrast, local areas in Gabon, northern DRC and Tanzania, southern Zambia, eastern Botswana, much of Zimbabwe, Malawi, much of Mozambique, local areas in Tanzania and South Africa, and much of Madagascar had above-average rainfall. During the past 90 days, Liberia, southern CAR, local areas in northern DRC, western Gabon, portions of South Sudan Republic, local areas in Tanzania, eastern Zimbabwe, central and southern Mozambique, southern Malawi, local areas in northern Botswana, and portions of eastern Madagascar had above-average rainfall. Below-average rainfall was observed over portions of Equatorial Guinea, southern Congo-Brazzaville, portions of Kenya, southern Somalia, Angola, Central and Southern DRC, Zambia, northern Malawi, and eastern South Africa. Week-1 outlooks call for an increased chance for below-average rainfall over Equatorial Guinea, Gabon, Congo-Brazzaville, much of DRC, northern Angola, Botswana and Zimbabwe. In contrast, there is an increased chance for above-average rainfall over eastern Zambia, much of Malawi, southern Tanzania, Mozambique and Madagascar.