It is often said that in Cape Town you can experience all four seasons in one day as the weather can change quite suddenly.
In particular it can rain quite heavily for a half an hour and then be a lovely clear sunny day. In September you can expect to see the sun the
wind and the rain on most days.
September is the end of winter and the start of Spring in South Africa – Capetonians tend to
think that if the temperature drops below 21°C (70°F) it is really cold so this is the time when they start to recover from the winter – when
temperatures can get as low as 12°C (54°F).
In the first week of September the average daily high temperature over the past
ten years is 19°C (66°F) with a maximum high of 37°C (99°F and a lowest high of 15°C (59°F) and an average low of 10°C - max 13° (55°F) min
5°C(41°F). Since 2004 there has been a 40% chance of some rain on any day; it has rained on average for 8% of the time – mostly light to moderate
rain.