You will always experience pleasant temperatures in Johannesburg. It has a subtropical highland climate and winter is sunny and mild. Summers are warm and get pretty wet. During summer it usually does not get any warmer than 33 °C and in winter temperatures are most days higher than 15 °C. During the night it can cool off quite a bit. Average temperature 24,7 °C in summer and 18,0 °C in winter.
Johannesburg is located in the eastern plateau area of South Africa known as the Highveld, at an elevation of 1,753 metres (5,751 ft) above sea level, so the climate is tempered by altitude, and it's pleasant and healthy (even though the city is polluted).
Being that the city is in the Southern Hemisphere, the seasons are reversed in comparison with Europe or North America. Since South Africa is located at the south of the equator line, the seasons are as follows.
Spring | : | September, October and November | |
Summer | : | December, January, February | |
Autumn | : | March, April, May | |
Winter | : | June, July, and August |
During the months of March, April, May, August and September you are most likely to experience good weather with pleasant average temperatures that fall between 20 degrees Celsius (68°F) and 26 degrees Celsius (79°F). The best months to visit Johannesburg are probably April, September and October, since they are mild months, not as rainy as summer and not as cold as winter. However, on closer view, Johannesburg can be visited throughout the year, since the summer is not too hot and it's sunny, even though it is disturbed by thunderstorms, while the winter is almost always mild and sunny during the day, although nights are often cold.