The African Monsoon Recent Evolution and Current Status Include Week-1 and Week-2 Outlooks Update prepared by Climate Prediction Center / NCEP 23 March.

The African Monsoon Recent Evolution and

Current Status

Include Week-1 and Week-2 Outlooks

Update prepared byClimate Prediction Center / NCEP

23 March 2015For more information, visit:http://www.cpc.ncep.noaa.gov/products/Global_Monsoons/African_Monsoons/precip_monitoring.shtml

Outline

• Highlights

• Recent Evolution and Current Conditions

• NCEP GEFS Forecasts

• Summary

Highlights:Last 7 Days

• Portions of the Gulf of Guinea and Central Africa countries, and coastal Tanzania received above-average rainfall.

• Suppressed rainfall continued to prevail over the Lake Victoria region, and portions of the Southern Africa countries.

• Week-1 outlooks call for an increased chance for above-average rainfall over southern Angola, northern Namibia, eastern DRC, Uganda, Rwanda Burundi, western Kenya, northwestern Tanzania, and southern Ethiopia and the neighboring areas of northern Kenya and Somalia. In contrast, there is an increased chance for below-average rainfall over Malawi, portions of southern Tanzania and eastern Zambia, eastern Zimbabwe, and northern Mozambique.

Rainfall Patterns: Last 7 Days

During the past seven days, above-average rainfall was observed over southern Cote d’Ivoire, southern Ghana, Togo, Benin, and central and southern Nigeria. Above-average rainfall was also observed over local areas in Cameroon, western Gabon, northern Congo Brazzaville, western DRC, northwestern Angola, eastern Tanzania, and local areas in Zimbabwe, Namibia and South Africa. In contrast, portions of CAR, South Sudan Republic, eastern DRC, Uganda, Rwanda, Burundi, many parts of Tanzania and Angola, much of Zambia, Malawi, Mozambique and Madagascar had below-average rainfall.

Rainfall Patterns: Last 30 Days

During the past 30 days, rainfall was above-average over portions of Cote d’Ivoire, central and southeastern Nigeria, western Gabon, eastern CAR, western South Sudan Republic, western and northern of DRC, southeastern Tanzania, northern Mozambique, and many parts of Madagascar. In contrast, much of Angola, eastern DRC, Rwanda, Burundi, Uganda, southeastern South Sudan Republic, portions of Ethiopia, Kenya and Tanzania, much of Zambia, Malawi, central and southern Mozambique, northern Namibia, Botswana, Zimbabwe, much of South Africa, and local areas in Madagascar had below-average rainfall.

Rainfall Patterns: Last 90 Days

During the past 90 days, rainfall was above-average over local areas in the Gulf of Guinea countries, portions of southern CAR and northern DRC, Malawi, northern Mozambique, and Madagascar. In contrast, Equatorial Guinea, Gabon, much of Angola, central and southern DRC, Namibia, western Botswana, northern Zambia, Tanzania, Uganda, portions of Ethiopia, Kenya, South Africa and southern Mozambique had below-average rainfall.

Rainfall Patterns: Last 180 Days

During the past 180 days, rainfall was above-average over parts of Guinea-Conakry, Liberia, western Cote d’Ivoire, local areas in Burkina Faso, southern CAR, western Gabon, portions of northern DRC, South Sudan Republic, portions of Ethiopia, local areas in Sudan, southern Malawi, northern Mozambique, and central and southern Madagascar. In contrast, portions of Cameroon, Equatorial Guinea, eastern Gabon, southern Congo-Brazzaville, Angola, southern DRC, Namibia, portions of Botswana, Zambia, and portions of South Africa had below-average rainfall.

Recent Rainfall Evolution

Daily evolution of rainfall over the last 90 days at selected places reflects that moderate to heavy rainfall helped to offset accumulated rainfall deficits over southern Nigeria (top-left panel), whereas it helped to erode some of the seasonal rainfall deficits over eastern Tanzania (bottom-right panel) and Ethiopia (top-right panel).

Atmospheric Circulation:Last 7 Days

The 850hpa wind anomalies (left panel) featured easterly flow across the Lake Victoria region and its associated convergence over the western parts of Equatorial Africa.

NCEP GEFS Model ForecastsNon-Bias Corrected Probability of

precipitation exceedance Week-1: Valid 24 March – 30 March 2015

Week-2: Valid 31 March – 6 April 2015

For week-1 (left panel), there is an increased chance for rainfall to exceed 50 mm over portions Cameroon, DRC, southern Ethiopia, the Lake Victoria region, Angola and portions of Namibia and southern Botswana.

Week-1 Precipitation Outlooks

24 March – 30 March 2015

1. There is an increased chance for above-average rainfall over southern Angola and northern Namibia: Anomalous lower-level westerly flow from the Atlantic Ocean with its associated lower-level convergence is expected to enhance rainfall in the region. Confidence: Moderate

2. There is an increased chance for above-average rainfall over eastern DRC, Uganda, Rwanda Burundi, western Kenya and northwestern Tanzania: Anomalous lower-level convergence, combined with the projected phase of the MJO is expected to enhance rainfall in the region. Confidence: Moderate

3. There is an increased chance for above-average rainfall over southern Ethiopia and the neighboring areas of northern Kenya and Somalia: Anomalous lower-level southeasterly flow from the Indian Ocean with its associated lower-level convergence is expected to enhance rainfall in the region. Confidence: Moderate

4. There is an increased chance for below-average rainfall over Malawi, portions of southern Tanzania and eastern Zambia, eastern Zimbabwe, and northern Mozambique: Anomalous lower-level anti-cyclonic circulation near the Mozambique Channel is expected to suppress rainfall in the region. Confidence: Moderate

Week-1 Precipitation Outlooks

31 March – 6 April 20151. There is an increased chance for above-average rainfall

over southeastern Nigeria, Cameroon, Equatorial Guinea, Gabon, Congo-Brazzaville, western CAR and western DRC: Anomalous lower-level convergence coupled with upper-level divergence is expected to enhance rainfall in the region. Confidence: Moderate

2. There is an increased chance for below-average rainfall over southern Ethiopia, eastern Uganda, Kenya, and portions of southern Somalia and northern Tanzania: Anomalous lower-level dry northerly flow with its associated lower-level divergence is expected to suppress rainfall in the region. Confidence: Moderate

Summary

• During the past seven days, above-average rainfall was observed over southern Cote d’Ivoire, southern Ghana, Togo, Benin, and central and southern Nigeria. Above-average rainfall was also observed over local areas in Cameroon, western Gabon, northern Congo Brazzaville, western DRC, northwestern Angola, eastern Tanzania, and local areas in Zimbabwe, Namibia and South Africa. In contrast, portions of CAR, South Sudan Republic, eastern DRC, Uganda, Rwanda, Burundi, many parts of Tanzania and Angola, much of Zambia, Malawi, Mozambique and Madagascar had below-average rainfall.

• During the past 30 days, rainfall was above-average over portions of Cote d’Ivoire, central and southeastern Nigeria, western Gabon, eastern CAR, western South Sudan Republic, western and northern of DRC, southeastern Tanzania, northern Mozambique, and many parts of Madagascar. In contrast, much of Angola, eastern DRC, Rwanda, Burundi, Uganda, southeastern South Sudan Republic, portions of Ethiopia, Kenya and Tanzania, much of Zambia, Malawi, central and southern Mozambique, northern Namibia, Botswana, Zimbabwe, much of South Africa, and local areas in Madagascar had below-average rainfall.

• During the past 90 days, rainfall was above-average over local areas in the Gulf of Guinea countries, portions of southern CAR and northern DRC, Malawi, northern Mozambique, and Madagascar. In contrast, Equatorial Guinea, Gabon, much of Angola, central and southern DRC, Namibia, western Botswana, northern Zambia, Tanzania, Uganda, portions of Ethiopia, Kenya, South Africa and southern Mozambique had below-average rainfall.

• Week-1 outlooks call for an increased chance for above-average rainfall over southern Angola, northern Namibia, eastern DRC, Uganda, Rwanda Burundi, western Kenya, northwestern Tanzania, and southern Ethiopia and the neighboring areas of northern Kenya and Somalia. In contrast, there is an increased chance for below-average rainfall over Malawi, portions of southern Tanzania and eastern Zambia, eastern Zimbabwe, and northern Mozambique.