According to the South African Weather Services, forecasting systems currently suggest an increased likelihood of an El Nino phase to develop towards the southern hemisphere spring season.
At this stage it is still too early to predict the impact on the next summer season (2017/18) over Southern Africa. However, historically it May have a negative impact on summer rainfall.
It will be recalled that sea surface temperature (SST) values in the Equatorial Pacific have to consistently be 1°C (or more) warmer than normal, for an El Nino condition to be declared.
Whilst ENSO (El Nino Southern Oscillation) is not considered to be a significant driver of climate trends during the Southern African winter months. It is nevertheless important to continue to monitor changes in ENSO, as the state/phase of ENSO becomes an important feature of seasonal predictions in the summer months.

Seasonal forecast:
Rainfall
There is a significant amount of uncertainty in this product at the current time, as the forecasting systems tend to have difficulty in producing skillful forecasts during the winter season.
Moreover, a forecast for below normal rainfall over the summer rainfall region in May, June and July is not particularly significant as these months (at least for the interior of SA) are normally characterised as being almost entirely rain-free.
There is a hint that April, May and June might have a chance of above normal rainfall for Western Cape, however the seasonal forecast team do not have a high level of confidence in this particular aspect of the forecast