Africa: Drought and floods hazards assessment 26 Feb 2004

Report
from US Agency for International Development
Published on 25 Feb 2004


CCA Guidance for Gulf of Guinea Rainfall in March-May 2004 at One Month Lead
The Gulf of Guinea region is defined as that between 5N and 12N; 15W-10E. The prediction for Mar-Apr-May 2004 rainfall at one month lead (ggMAM1.gif) essentially calls for climatology over the region. There is one very weak signal of lower than climatological probability for rainfall in the southwest portion of the area. Over Africa, the heaviest rainfall continued to occur over the central and southern portion of the continent extending from Southern Cameroon to central Namibia in the west throughout the continent to southern Kenya and South Africa on the east. In particular, Lesotho received over 20 mm of rain and Swaziland about 50 mm during this period. Southern Madagascar and eastern Botswana continued to receive little or no rainfall.

Western Africa indicated widespread rainfall with up to 25 mm in some areas. Scattered showers were observed from northern Western Sahara through Morocco into northern Algeria with amounts up to about 50 mm in scattered locations.

NOAA/CPC USGS



Africa Weather Hazards Assessment Text Explanation
February 26 - March 3, 2004

1) Long term drought continues in the Sool Plateau region of northern Somalia due to poor rainfall during the past 5+ seasons. No improvement is likely until at least March as hydrological and agricultural problems remain.

2) Continued light showers were seen in parts of southern Ethiopia during the last week, though long term drought remains. Additional precipitation is not expected during the next period. No changes were seen during the past two months in parts of northeastern Ethiopia / western Somalia which are experiencing drought conditions due to poor rainfall the recent two seasons.

3) After a week of light showers throughout much of eastern Tanzania, precipitation increased during the past seven days, as weekly accumulations exceeded 75 mm in many areas. Dryness forecast during the last days of February may fit in well to recent erratic moisture patterns in the region, though hit and miss thunderstorms still may lead to locally heavy rains.

4) and 5) Long term drought continues in much of southern Mozambique, Swaziland, and eastern South Africa due to poor rainfall during the past few seasons. In areas of central and southern Mozambique, seasonal deficits continue to accumulate as high pressure continues to dominate the weather pattern around the area. Including much of east and southeastern Zimbabwe, substantial rains have not fallen since the end of January. Further to the south and west, areas in and around the Maize Triangle of South Africa, Swaziland, and Lesotho have seen an increase in precipitation during the past weeks, though the effects of an earlier failure remains. Agricultural damage has already taken its toll in much of the area, though any late-planted crops may feel positive effects of this increased moisture. Rains are forecast during the next week in these areas, though southeastern Zimbabwe and southern Mozambique will not likely receive similar accumulations.

6) Heavy rains have continued during the past week throughout much of western and central Zambia and neighboring regions, as river levels continue to rise. Most notably, the Mid to Upper Zambezi, Okavango, and Kafue Rivers are exhibiting increasing flows, and forecast precipitation will likely continue this trend. Reports downstream from near Victoria Falls and the Kariba Reservoir show effects of increased flows, though no flooding concerns are evident.

7) The first period of substantial precipitation since early December was seen last week throughout Morocco and northwestern Algeria. After a quick start to the rainy season in the area, rainfall decreased to next to nothing for nearly two and a half months, as agricultural and hydrological drought emerged. While the recent rains will increase moisture supply in the region, agricultural problems in many areas may be beyond restoration for this season.

Timothy Love