How can we see from this Synoptic Chart that it is summer in South Africa?
The South Atlantic High Pressure and South Indian High Pressure are far south
The Mid-latitude Cyclones are far south and will miss South Africa
There is a low pressure over all of South Africa
The temperatures are high over much of the country
The South Indian High Pressure is blocking the path of the Mid latitude Cyclones. This compresses the isobars ahead of the frontal systems and results in high wind due to a high pressure gradient force.
There is a low pressure off the east coast of Madagascar. Tropical cyclones develop in this region and sometimes reach South Africa. This low pressure can be clearly seen on the satellite image.
Despite the low pressure over much of the country, there is very little cloud.
You can see the Mid-latitude Cyclones on the satellite map.