Period: 1 - 10 May 2002
Review of the rainfall situation
Moderate rainfall over northeastern Tanzania.
This is the last bulletin for the season.
Tropical Cyclone Kesiny is no longer active.
Moderate rainfall expected over northeastern and coastal belt of Tanzania and northern DRC.
For, most of SADC, rainfall season has come to an end.
Moderate rainfall is expected over north eastern and coastal belt of Tanzania and northern DRC.
Remainder of the SADC region will be mainly dry.
Most of SADC, reported rainfall between 0 (zero) and 30mm. However, the mean ranifall for this dekad for Botswana, Lesotho, Malawi, Mauritius, Mozambique, Tanzania and Zimbabwe is 7.0, 11.0, 11.2, 24.6, 30.0, 42.0 and 3.6mm respectively, Fig. 1 . These are considerably less than the means during the peak of the season. This is an indication that the rainfall season has come to an end.
Meanwhile, the percentage of normal rainfall shows that most of SADC had below normal rainfall (less than 65%) except for the northwestern Tanzania, Lesotho and Mauritius where it was above normal.
EL-NINO/SOUTHERN OSCILLATION (ENSO) UPDATE
Warmer than normal sea surface and sub surface temperatures were observed throughout most of the equatorial Pacific during April 2002. Sea surface temperature anomalies were up to 2°C warmer than average in the region between the Galapagos Islands and the South American coast, and greater than 1°C warmer than average immediately to the west of 180°W. Although there was considerable warming in the eastern equatorial Pacific during February-April, there was little change in SSTs or subsurface temperature anomalies in the Nino regions. Atmospheric indices for low-level winds, sea level pressure (SOI) and precipitation (OLR) continue to indicate near-normal conditions, which is consistent with this lack of evolution of an El- Nino in the central equatorial Pacific.
There has been no additional significant Kelvin wave activity, which implies that a slow evolution towards possible El-Nino conditions is likely through the reminder of 2002.
The assessment agrees well with latest statistical and several coupled model prediction, which show a gradual warming over the next several months with weak to moderate El-Nino conditions by the end of 2002.
DMC in conjunction with our partners will continue to closely monitor the El- Niño situation and relevant updates will be issued from time to time.
The continental anticyclone over southern Africa remained the predominant feature and has maintained stable conditions as the winter season starts.
TROPICAL CYCLONE SEASON
Tropical Cyclone Kesiny, developed as a depression south of Seychelles on 2/5/2002 and matured on 9/5/2002. It moved in west-south-west direction and crossed the northern tip of Madagascar, eventually died overland.
DETAILED SECTOR SPECIFIC OUTLOOK FOR THE PERIOD 16 - 26 MAY 2002
EASTERN SECTOR: (Tanzania, Mozambique and Malawi)
Mostly dry except over the eastern and coastal belt of Tanzania and eastern Mozambique where light to moderate showers are anticipated.
CENTRAL SECTOR: (Zambia, Zimbabwe and Botswana)
The entire sector will be mostly dry.
INDIAN OCEAN ISLANDS : (Mauritius and Seychelles)
Light rains are expected over the sector.
SOUTH AND SOUTHWESTERN SECTOR: (South Africa, Lesotho, Swaziland and Namibia)
Mostly dry except for some light showers over Lesotho, Swaziland and southeastern South Africa.
NORTHWESTERN SECTOR : (DRC and Angola)
Light to moderate showers over the north DRC but mostly dry elsewhere.