Ten-day Drought Watch for Southern Africa Issue No. 19
Period: 21 - 30 April 2002
Review of the rainfall situation
Above normal rainfall over Namibia and northern Tanzania.
Data not received from Angola, Botswana, Mauritius, Swaziland, South Africa and Zambia.
The southern parts of the SADC are in transition period (Summer - Winter).
Tropical Cyclone Kesiny is currently active.
Northern parts of Tanzania, northern Angola and most of DRC are expected to have moderate rainfall.
Likelihood of Tropical Cyclone Kesiny affecting some of the SADC countries.
Moderate falls are expected over most parts of the DRC, central Mozambique, northern Tanzania and northern Angola. There is also a likelihood of moderate rains over Mauritius.
The rest of the region will be mostly dry.
Most of DRC, northern Tanzania and Seychelles had between 30 to 150mm. The rest of SADC had below 30mm.
Namibia, northern Tanzania and some coastal areas of Mozambique had normal to above rainfall. The remainder of the region had below normal rainfall.
In cases where actual rainfall data were not received, satellite imagery was used . Rainfall estimates show significant falls over northwestern Angola. No or little rains were estimated over Botswana, South Africa, Swaziland, and Zambia.
EL-NINO/SOUTHERN OSCILLATION (ENSO) UPDATE
The development of a warm (El- Niño) episode continued in the equatorial Pacific during March 2002. Warmer than normal sea surface and sub surface temperatures were observed throughout most of the equatorial Pacific. The warming is said to have affected Peruvian marine fisheries, where the cold-water anchovy has been replaced by tropical species. It is likely that these conditions represent the early stages of El- Niño.
The warming of surface and subsurface waters in the eastern equatorial Pacific was due to the arrival of an oceanic Kelvin wave that propagated eastward from the central equatorial Pacific starting in mid December.
The latest statistical and coupled model predictions show a spread from near normal conditions to moderate warm episode conditions during the remainder of 2002.
DMC will continue closely monitoring the El- Niño situation together with collaborating partners and relevant updates will be issued from time to time.
The middle level anticyclone over Botswana was the predominant feature. However, some transient frontal systems gave some significant rains to the southwestern parts of the region.
The zonal arm of the ITCZ continued to affect much of the DRC and northern Tanzania .
TROPICAL CYCLONE SEASON
Although, the tropical cyclone season is drawing towards an end, a Tropical Cyclone Kesiny developed on 2 May 2002. Currently, severe Tropical storm with a central pressure of 976hPa is moving west-south-westwards at a speed of 6 knots.
According to the Meteo-France/Tropical Cyclone Centre/La Reunion the tropical cyclone Kesiny is expected to intensify.
DETAILED SECTOR SPECIFIC OUTLOOK FOR THE PERIOD 06 - 16 MAY 2002
The middle level trough is expected to affect the southern parts of the sub-region resulting in a few showers. Meanwhile, the zonal arm of the ITCZ is expected to continue affecting the extreme northern areas.
The latest Satellite imagery, Fig.5 , shows Tropical cyclone Kesiny to the northeast of Madagascar, which might affect some SADC countries.
EASTERN SECTOR: (Tanzania, Mozambique and Malawi)
Southern Malawi, central Mozambique and northern Tanzania are expected to receive light to moderate rains. The rest of the sector would remain dry.
CENTRAL SECTOR: (Zambia, Zimbabwe and Botswana)
The entire sector will be mainly dry.
INDIAN OCEAN ISLANDS : (Mauritius and Seychelles)
Light rains are expected over Seychelles for the early part of the forecast period. Moderate rains are likely over Mauritius.
SOUTH AND SOUTHWESTERN SECTOR: (South Africa, Lesotho, Swaziland and Namibia)
A few showers are expected in the early part of the period becoming mostly dry thereafter.
NORTHWESTERN SECTOR : (DRC and Angola)
Lights to moderate rains are expected over most of DRC except southern areas. Angola will be mostly dry except for the northern areas.