Update  

 Latest GFS model guidence as well as EURO (ECMWF) guidence is showing the possibility of some very extreme weather for maritime travellers off to the south of South Africa. The EURO is showing wind speeds in excess of 90km/h. This would make sense given the latest intensity of the low pressure system which appears to be deepening to around 930hpa.  I would advise those planning on being on the water this weekend to keep an eye on the local weather forecasts as winds may reach strong gales and large swells also becoming possible. Though it's important to note that this system is still days away and the model data will change from run to run.

Model information is showing the progression of two frontal weather systems set to influence weather in the Western Cape and possibly southern areas of the Eastern Cape later on in the period. The first of the systems is a cut-off low with a cold front which is expected to develop off the south west of the Western Cape (as can be seen in the first image below) from Tuesday 12th May and deepen a bit on Wednesday, this system will remain fairly shallow and while it is likely to bring some decent rainfall and some moderate winds the main system will develop behind this.