Weather and climate in Johannesburg (South Africa)

In Johannesburg, the largest city of South Africa, the climate is subtropical, with mild, sunny winters (when, however, nights are cold) and pleasantly warm summers, usually sunny, but with some afternoon thunderstorms. The city is located near the Tropic, but also on a plateau at 1,700 meters (5,600 feet) 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.
The average temperature goes from 10 °C (50 °F) in June and July to 21 °C (70 °F) in January. Here are the average temperatures.

Rainfall amounts to 700 millimeters (27.5 inches) per year and is concentrated in the warm period, from October to March, when the rains occur in the form of downpours or thunderstorms. On the contrary, winter is a dry season, with rare and sporadic rains. Here is the average precipitation.

Winter, from May to August, is mild and sunny during the day, but nights are cold. In the coldest months, June and July, the minimum temperature is near freezing (0 °C or 32 °F), especially in the outskirts of the city and in the countryside, where light frosts can occur.
The cold record is even -8 °C (17 °F), recorded on June 13, 1979.
In the daytime, however, when the sun usually shines, the air becomes mild, and the maximum temperature hovers around 18/20 °C (64/68 °F). In August, the temperature already begins to increase a bit.
Every once in a while, however, cold air masses arrive here from the south, and in these cases, the maximum temperature can remain around 10 °C (50 °F).
Since winter is a dry season, and as mentioned, the air is usually mild during the day, snow is a very rare phenomenon; sometimes, however, a bit of light snow can fall in the early morning. Snowfalls with accumulation on the ground, however, are not impossible, in fact, they occurred in May 1956, in August 1962, in June 1964, in September 1981, and more recently, on June 28, 2007, and on August 7, 2012. In nearby Pretoria, located at a bit lower altitude, snow is even more rare.

Summer, from November to March, is pleasantly warm, with cool nights, and possible showers and thunderstorms in the afternoon or in the evening. Hot days are rare, in fact, the temperature rarely exceeds 30 °C (86 °F), but the tropical sun at high altitudes is very strong, so it requires appropriate protection.
However, the temperature reached 36 °C (97 °F) in January 2016.

Spring and autumn are mild and sunny, although sometimes, in April and September, it can get cold at night, while in October, there is often summer-like weather, warm during the day, and with the first thunderstorms.



Since the sky is usually clear, the amount of sunshine in Johannesburg is very good throughout the year, even though the least sunny season is the summer because of showers and thunderstorms, which, however, do not last long and soon give way to the sun. There are as many as 3,100 hours of sunshine per year. Here are the average sunshine hours per day.

Best Time

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. The choice may therefore depend on the itinerary: for example, if you want to visit the Kruger Park, in the north-east of South Africa, you can choose winter, from June to August, a period that can be a bit cold and also rainy in the south of the country.

Johannesburg - Climate data

The average temperature of the coldest month (July) is of 10.7 °C (51.3 °F), that of the warmest month (January) is of 20.4 °C (68.8 °F). Here are the average temperatures.
Precipitation amounts to 705 millimeters (27.8 inches) per year: so, it is at an intermediate level. It ranges from 5 mm (0.2 in) in the driest months (July, August) to 125 mm (4.9 in) in the wettest one (January). Here is the average precipitation.
There are on average around 3125 sunshine hours per year. Here are the average hours of sunshine per day.

Johannesburg - Weather by month

Based on the period 1991-2020

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January, the warmest month of the year, is generally a warm month. The average temperature is of 20.4 °C (69 °F), with a minimum of 14.6 °C (58.3 °F) and a maximum of 26.3 °C (79.3 °F).
On the coldest nights of the month, the temperature usually drops to around 10 °C (50 °F).
On the warmest days of the month, the temperature usually reaches around 30.5 °C (87 °F).
Precipitation amounts to 125 mm (4.9 in), distributed over 14 days.
The day lasts on average 13 hours and 35 minutes.
There are on average 8 hours of sunshine per day. So, the sun shines 59% of the time.
The average humidity is 69%.
The average wind speed is 14 kph (8 mph).

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February is generally a warm month. The average temperature is of 20.3 °C (69 °F), with a minimum of 14.4 °C (57.9 °F) and a maximum of 26.3 °C (79.3 °F).
On the coldest nights of the month, the temperature usually drops to around 10.5 °C (51 °F).
On the warmest days of the month, the temperature usually reaches around 29.5 °C (85.5 °F).
Precipitation amounts to 90 mm (3.5 in), distributed over 10 days.
The day lasts on average 13 hours and 0 minutes.
There are on average 8 hours of sunshine per day. So, the sun shines 61% of the time.
The average humidity is 68%.
The average wind speed is 13 kph (8 mph).

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March is generally a warm month. The average temperature is of 19.1 °C (66 °F), with a minimum of 13.2 °C (55.7 °F) and a maximum of 25 °C (77.1 °F).
On the coldest nights, the temperature usually drops to around 8.5 °C (47.5 °F).
On the warmest days, the temperature usually reaches around 28.5 °C (83.5 °F).
Precipitation amounts to 90 mm (3.5 in), distributed over 11 days.
The day lasts on average 12 hours and 10 minutes.
There are on average 7.5 hours of sunshine per day. So, the sun shines 63% of the time.
The average humidity is 67%.
The average wind speed is 12 kph (7 mph).

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April is generally a very mild month. The average temperature is of 16.4 °C (62 °F), with a minimum of 10.2 °C (50.4 °F) and a maximum of 22.7 °C (72.8 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 4.5 °C (40 °F).
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 26 °C (79 °F).
Precipitation amounts to 50 mm (2 in), distributed over 8 days.
The day lasts on average 11 hours and 25 minutes.
There are on average 8 hours of sunshine per day. So, the sun shines 69% of the time.
The average humidity is 62%.
The average wind speed is 12 kph (8 mph).

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May is generally a mild month. However, there are remarkable differences between night and day. The average temperature is of 13.7 °C (57 °F), with a minimum of 7.1 °C (44.8 °F) and a maximum of 20.4 °C (68.6 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 0.5 °C (32.5 °F).
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 24 °C (75.5 °F).
Precipitation amounts to 15 mm (0.6 in), distributed over 3 days.
The day lasts on average 10 hours and 50 minutes.
There are on average 9 hours of sunshine per day. So, the sun shines 82% of the time.
The average humidity is 50%.
The average wind speed is 12 kph (7 mph).

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June is generally a mild month. However, there are remarkable differences between night and day. The average temperature is of 11.0 °C (52 °F), with a minimum of 4.2 °C (39.5 °F) and a maximum of 17.9 °C (64.3 °F).
On the coldest nights, the temperature usually drops to around -2 °C (28.5 °F).
On the warmest days, the temperature usually reaches around 21.5 °C (71 °F).
Precipitation amounts to 10 mm (0.4 in), distributed over 2 days.
The day lasts on average 10 hours and 30 minutes. June 21, the winter solstice, is the shortest day of the year in the Southern Hemisphere.
There are on average 9 hours of sunshine per day. So, the sun shines 85% of the time.
The average humidity is 48%.
The average wind speed is 13 kph (8 mph).

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July, the coldest month of the year, is generally a mild month. However, there are remarkable differences between night and day. The average temperature is of 10.7 °C (51 °F), with a minimum of 3.6 °C (38.6 °F) and a maximum of 17.8 °C (64.1 °F).
On the coldest nights of the month, the temperature usually drops to around -2.5 °C (27.5 °F).
On the warmest days of the month, the temperature usually reaches around 22 °C (71.5 °F).
Precipitation amounts to only 5 mm (0.2 in), and all occurs in one day.
The day lasts on average 10 hours and 40 minutes.
There are on average 9 hours of sunshine per day. So, the sun shines 86% of the time.
The average humidity is 45%.
The average wind speed is 13 kph (8 mph).

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August is generally a mild month. However, there are remarkable differences between night and day. The average temperature is of 13.4 °C (56 °F), with a minimum of 6 °C (42.9 °F) and a maximum of 20.8 °C (69.4 °F).
On the coldest nights of the month, the temperature usually drops to around -0.5 °C (31 °F).
On the warmest days of the month, the temperature usually reaches around 25.5 °C (77.5 °F).
Precipitation amounts to only 5 mm (0.2 in), distributed over 2 days.
The day lasts on average 11 hours and 10 minutes.
There are on average 9 hours of sunshine per day. So, the sun shines 82% of the time.
The average humidity is 42%.
The average wind speed is 15 kph (9 mph).

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September is generally a very mild month. However, there are remarkable differences between night and day. The average temperature is of 17.0 °C (63 °F), with a minimum of 9.4 °C (49 °F) and a maximum of 24.6 °C (76.3 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 2.5 °C (36.5 °F).
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 29.5 °C (84.5 °F).
Precipitation amounts to 25 mm (1 in), distributed over 4 days.
The day lasts on average 12 hours and 0 minutes.
There are on average 9.5 hours of sunshine per day. So, the sun shines 78% of the time.
The average humidity is 41%.
The average wind speed is 16 kph (10 mph).

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October is generally a warm month. However, there are remarkable differences between night and day. The average temperature is of 18.7 °C (66 °F), with a minimum of 11.4 °C (52.4 °F) and a maximum of 26 °C (78.7 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 5 °C (40.5 °F).
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 30.5 °C (87.5 °F).
Precipitation amounts to 75 mm (3 in), distributed over 9 days.
The day lasts on average 12 hours and 40 minutes.
There are on average 8.5 hours of sunshine per day. So, the sun shines 69% of the time.
The average humidity is 52%.
The average wind speed is 17 kph (10 mph).

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November is generally a warm month. However, there are remarkable differences between night and day. The average temperature is of 19.2 °C (67 °F), with a minimum of 12.5 °C (54.6 °F) and a maximum of 25.8 °C (78.4 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 6 °C (43 °F).
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 30 °C (86.5 °F).
Precipitation amounts to 110 mm (4.3 in), distributed over 13 days.
The day lasts on average 13 hours and 25 minutes.
There are on average 8.5 hours of sunshine per day. So, the sun shines 62% of the time.
The average humidity is 61%.
The average wind speed is 16 kph (10 mph).

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December is generally a warm month. The average temperature is of 20.1 °C (68 °F), with a minimum of 14 °C (57.2 °F) and a maximum of 26.1 °C (79 °F).
On the coldest nights of the month, the temperature usually drops to around 9 °C (48.5 °F).
On the warmest days of the month, the temperature usually reaches around 30 °C (86 °F).
Precipitation amounts to 105 mm (4.1 in), distributed over 14 days.
The day lasts on average 13 hours and 50 minutes. December 21, the summer solstice, is the longest day of the year in the Southern Hemisphere.
There are on average 8.5 hours of sunshine per day. So, the sun shines 62% of the time.
The average humidity is 67%.
The average wind speed is 15 kph (10 mph).