SWAZILAND SEASONAL RAINFALL FORECAST FOR THE 2010/11 SEASON

Overview

The country’s seasonal rainfall outlook for the 2010/11 show an increased chance of Normal to Above-Normal Rainfall over most parts of the country during the October-November-December (OND) 2010 period. There is an increased chance for Above-Normal rainfall in the western half of the country with a Normal to below-Normal chance over the Eastern half of the country during the January, February and March (JFM) 2011 period. A regional perspective forecast for the entire season is presented below starting with the OND period;

October-November-December (OND) 2010 Rainfall forecast

There is an increased chance for Normal-to-Above-Normal rainfall throughout the country during the October – November – December (OND) period of the 2010/11 season, with a bias of Above-Normal to Normal rainfall in the Middleveld and Lubombo Plateau zones. The Highveld and Lowveld zones are likely to receive Normal Rainfall during OND.

The regional breakdown of the predicted OND rainfall probabilities are as presented below:

Highveld

There is a chance of Normal-to-Above-Normal Rainfall in this region during the October-November-December (OND) 2010 period.

Middleveld

There is a high chance for Above-Normal-to-Normal Rainfall over most parts of this region during the OND 2010 period.

Ntfonjeni Lowveld -25.80

Piggs Peak ManangaLomahasha There is an increased chance for -26.00 Normal to Above-Normal Rainfall 40 35 35 over most parts of this region -26.20 Motshane RDA 40 during the OND 2010 period. Mbabane 25 35 40Luve RDA 25 -26.40 40 35 KalangaSiteki Lubombo Matsapha 25 Malkerns 25 Tikhuba -26.60 Mankayane Siphofaneni There is a chance for Above- Normal to Normal Rainfall in this Mhlangatsha Bigbend -26.80 Sithobela region during the OND 2010 period. SRDASandleni Nsoko -27.00 MahmbaNhlangano RDA Hluthi RDA Category -27.20 Lavumisa Above Normal -27.40 30.80 31.00 31.20 31.40 31.60 31.80 32.00 32.20 Below

January –February –March (JFM) 2011 Rainfall

The July predictor (SST) used currently puts most of the western parts of the country in Above-Normal to Normal rainfall while the eastern parts of the country in a Normal to Below-Normal category. The regional breakdown of the predicted January-February-March (JFM) 2011 rainfall probabilities are Ngonini -25.80 Mayiwane as presented below:

Bulembu Border Piggs Peak ManangaLomahasha Mhlume Highveld -26.00 Homsted Malolotja Nokwane Mpala Simunye Foyers -26.20 25 There is an increased 40 Mbabane 40Luve 40 chance of Above-Normal to 35 35 Mpaka25 Normal rainfall over most -26.40 Mpisi KalangaSiteki35 25 MalkernsMatsapha25 40 areas within the region during Usutud4 Sanroy Tikhuba -26.60 Mankayane Siphofaneni35 the JFM period. Latitude Tambuti Bloemond Kubuta StPhillipsBigbend Middleveld -26.80 Sithobela

SRDA Nsoko -27.00 Sandleni There is an increased Nhlangano chance of Above-Normal to Hlutsi -27.20 Normal rainfall over most of Nsalitje Lavumisa the region during the forecast

-27.40 period, JFM 2011. 30.80 31.00 31.20 31.40 31.60 31.80 32.00 32.20 Longitude Category

Above

Normal Lowveld Below

There is a chance for Normal to Below-Normal rainfall over the Lowveld region during the JFM period.

Lubombo

There is a chance for Normal to Below-Normal rainfall over the Lubombo Plateau during the JFM 2011 period.

Conclusion

Presently, seasonal-to-inter-annual forecasting allows predictions for large areas over seasonal timescales. This means that, seasonal forecasts may not fully account for all factors that influence local and time specific climate variability. Shorter timescale climate variations may occur, which can be determined through daily and ten-day weather forecasts and monthly climate outlooks. The Swaziland Meteorological Service will continuously provide updates monthly during the season.

For more information contact:

Emmanuel D. Dlamini Director Swaziland Meteorological Services P. O. Box 58 Mbabane

Tel:- 404 8859 or 404 6724 Fax:- 404 1530 Email:- [email protected]