Gauteng, South Africa · population 2,026,469 · 91 weather stations within 200 km · records 1859 to 2025
Johannesburg has an average annual daytime high of 23.1°C, based on the 1951 to 1980 baseline. Its warmest month is January, when highs typically reach 26.3°C, and its coldest is July, with overnight lows near 1.0°C.
These figures reflect annual averages, not single-day records. Daily observations are outside this dataset's precision.
Since 1900, Johannesburg's average temperature has risen by +1.6°C. Compared to the earliest station records that begin in 1859, warming totals +1.7°C.
20-year smoothed annual temperature reconstructed from station anomalies. Dashed line: 1951–1980 baseline.
Daytime highs sit within a comfortable 15°C to 26°C range.
Johannesburg's average annual daytime high is 23.1°C, based on the 1951 to 1980 baseline period. The warmest month is January, with highs averaging 26.3°C, and the coldest is July, with lows averaging 1.0°C.
January is the warmest month in Johannesburg, with typical daytime highs of 26.3°C.
2015 is the hottest year on record for Johannesburg, running +2.0°C above the 1951 to 1980 baseline.
Yes. Since 1900, Johannesburg has warmed by roughly +1.6°C.
March to December typically offers the most comfortable daytime highs, in the 15°C to 26°C range.
Baseline period 1951 to 1980. Monthly averages are the mean of station observations weighted by proximity. Warming trend is the 20-year smoothed anomaly against that baseline.