Last updated: August 31, 2025
December in Johannesburg, South Africa showcases a dynamic blend of weather, characterized by maximum temperatures soaring to 34°C (93°F), while the average temperature hovers around a comfortable 20°C (69°F). As the month progresses, residents and visitors experience minimum temperatures dipping to a chilly 10°C (50°F) at night. With humidity levels reaching a substantial 81%, the city feels lush and vibrant. Rainfall is prevalent, with 146 mm (5.7 in) of precipitation spread across 19 days, adding a refreshing twist to the summer heat and contributing to the region's lush landscapes.
In December, Johannesburg, South Africa, experiences a warm climate with temperatures ranging from a minimum of 10°C (50°F) to a sizzling maximum of 34°C (93°F). The average temperature hovers around 20°C (69°F), providing a comfortable backdrop for outdoor activities and holiday festivities. This month marks a transition into summer, with temperatures steadily rising from the cooler months of April and May. The warmest temperatures are accompanied by an increase in rainfall, typical of the South African summer, making December a vibrant and lively time in the city. As the year draws to a close, Johannesburg's warm and sunny days invite both locals and tourists alike to soak up the festive atmosphere.
December is a notably wet month in Johannesburg, South Africa, with precipitation peaking at 146 mm (5.7 in) across an average of 19 rainy days. This increase in rainfall marks a significant rise compared to the preceding months, particularly after the lower totals in the dry winter, where July recorded only 2 mm (0.1 in). As summer approaches, December's abundant rains contribute to the vibrant greenery of the landscape, invigorating the city just before the year closes. The trend of higher precipitation continues from November, which sees 97 mm (3.8 in), setting the stage for December's climactic rainfall—a clear signal that Johannesburg transforms into a wetter and livelier environment as the festive season unfolds.
In December, Johannesburg experiences a humidity level of 81%, marking a subtle uptick that aligns with the wetter season. This increase follows November's peak of 82%, reflecting a trend where the city sees its highest humidity levels during the late spring and early summer months. As the year progresses from the drier winter months of June and July, which see humidity dip to around 71% and 73% respectively, we observe a gradual rise in humidity from August onwards. Overall, December's humidity showcases Johannesburg's transition into summer, bringing warmth and moisture that enhance the city's vibrant atmosphere.
In December, Johannesburg experiences a notably high UV Index of 16, categorizing its exposure as extreme. This means that unprotected skin may burn in as little as 10 minutes, underscoring the need for diligent sun protection during this time. Following a trend of increasing intensity from the beginning of summer, December’s UV levels continue to rise compared to earlier months, which were already characterized by high UV ratings. As the heat intensifies, residents and visitors should remain vigilant and plan outdoor activities accordingly. For more details on UV levels throughout the year, visit Johannesburg UV Index.
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In Johannesburg, South Africa, December shines as a radiant conclusion to the year, boasting an impressive 371 hours of sunshine. This month marks a delightful trend, as daylight hours peak during the summer season, just slightly surpassing the 370 hours recorded in November. The city's sunshine consistently escalates from the drier winter months, with a gradual ascent beginning in October, when the sun blesses residents with 362 hours. Each subsequent month, from August's 329 hours to December, showcases a stunning upward trajectory, providing the perfect backdrop for outdoor activities and festive celebrations in this vibrant city. As the warm sun bathes Johannesburg, it’s clear that December not only lights up the skies but also lifts the spirit of all who gather under its golden glow.
In Johannesburg, the likelihood of sunny weather in December stands at 41%, marking a noticeable shift as the year transitions towards summer. This percentage is relatively modest compared to the sunnier months leading up to December, where the chances peak at an impressive 95% in July. The trend shows a gradual increase in sunshine from the cooler months of April through October, with November also experiencing a steady 60% likelihood of clear skies. However, come December, the sunny outlook begins to wane, hinting at the possible onset of summer rains. Thus, while December still offers some sunny days, it's less reliable than the preceding months, leaving room for a mix of weather patterns to shape holiday plans.
In December, Johannesburg, South Africa basks in an average of 13 hours of daylight, marking the height of summer and the season’s longest days. This pattern of extended daylight begins to emerge in late spring, with November also offering 13 hours, while the trend starts its gradual ascent in October with 12 hours. Following the shorter days of winter from May to July, where daylight is limited to 10 hours, a clear increase is observed as the year progresses. The gradual shift from 11 hours in August and September to the peak of 13 hours in December showcases Johannesburg's vibrant summer, making it a perfect time to enjoy outdoor activities and bask in the sun's warmth.
In Johannesburg, December brings a gentle average wind speed of 3.3 m/s (7 mph), providing a refreshing contrast to the summer heat. Notably, this month sees a slight uptick from the calmer months of March through May, which were marked by consistent winds around 2.6 to 2.7 m/s. The winds tend to pick up as the year progresses, peaking in November at 4.2 m/s (9 mph) before settling into the moderately breezy December. This mild windswept atmosphere complements the festive spirit of the holiday season, making it a delightful time to enjoy outdoor activities amidst the vibrant surroundings. Thus, December serves as a transitional month, blending lower wind speeds from earlier months with the livelier gusts that herald the upcoming months of summer.
Weather in Johannesburg varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Johannesburg, focusing on differences in temperature, rainfall, humidity, and UV levels.
In December, temperatures in Johannesburg range from a minimum of 10°C (50°F) to a maximum of 34°C (93°F), with an average of 20°C (69°F). The month sees significant precipitation, totaling 146 mm (5.7 in) over 19 days, accompanied by higher humidity at 81%. Conversely, January presents slightly cooler conditions, with a minimum of 9°C (48°F) and a maximum of 33°C (92°F), while still maintaining the same average temperature of 20°C (69°F). Precipitation decreases to 130 mm (5.1 in) over just 14 days, and humidity also drops to 79%. For more insights about January's weather specifics, you can visit Johannesburg weather in January.
In December, Johannesburg experiences warmer weather with temperatures ranging from a minimum of 10°C (50°F) to a maximum of 34°C (93°F), while in February, the temperature slightly decreases, peaking at 31°C (87°F). Both months have an average temperature of around 20°C (69°F), but December tends to be more humid, with humidity levels at 81% compared to February's 77%. Precipitation is also more frequent in December, with 146 mm (5.7 in) falling over 19 days, whereas February sees less rainfall at 138 mm (5.4 in) over 16 days. For more detailed weather information, check out Johannesburg weather in February.
In December, Johannesburg experiences warmer weather, with temperatures ranging from a minimum of 10°C (50°F) to a maximum of 34°C (93°F) and an average of 20°C (69°F). The month is also characterized by higher humidity at 81% and significant precipitation, totaling 146 mm (5.7 in) over 19 days. In contrast, March brings slightly cooler temperatures, with a minimum of 8°C (46°F), an average of 19°C (66°F), and a maximum of 30°C (86°F). This month sees less precipitation, amounting to 79 mm (3.1 in) over just 10 days, with humidity slightly lower at 77%. For more detailed information, you can check out Johannesburg weather in March.
In December, Johannesburg experiences much warmer weather, with average temperatures ranging from a minimum of 10°C (50°F) to a maximum of 34°C (93°F). The month is characterized by significant precipitation, totaling 146 mm (5.7 in) over 19 days, contributing to a humid atmosphere with a consistent humidity level of 81%. In contrast, April brings cooler temperatures, with a minimum of 3°C (38°F) and a maximum of 29°C (85°F), and an average temperature of 16°C (61°F). Precipitation in April is considerably less, at 63 mm (2.5 in) over only 10 days, while humidity remains steady at 81%. For more detailed information, you can check Johannesburg weather in April.
In comparing the weather between December and May, December tends to be significantly warmer, with temperatures ranging from a minimum of 10°C (50°F) to a maximum of 34°C (93°F), and an average of 20°C (69°F). This month is also characterized by high humidity at 81% and considerable rainfall, receiving 146 mm (5.7 in) over 19 days. In contrast, May offers a much cooler climate, featuring temperatures from a minimum of -1°C (30°F) to a maximum of 26°C (78°F), with an average of 13°C (56°F). The precipitation is minimal in May, with only 13 mm (0.5 in) spread over just one day, while humidity remains slightly higher at 82%. For more specific insights into Johannesburg's May weather, you can visit Johannesburg weather in May.
When comparing December and June weather, December is characterized by warm temperatures with a minimum of 10°C (50°F) and an average of 20°C (69°F), peaking at a maximum of 34°C (93°F). It also experiences considerable precipitation, with 146 mm (5.7 in) over 19 days, contributing to a high humidity of 81%. In contrast, June presents much cooler conditions, featuring minimum temperatures of -4°C (24°F) and an average of 11°C (51°F), with a maximum of 24°C (76°F). The month is notably dry, receiving only 6 mm (0.2 in) of rain over just 1 day, along with lower humidity at 73%. For a detailed look at the weather patterns during this month, check out Johannesburg weather in June.
December and July present contrasting weather patterns in Johannesburg. In December, temperatures range from a mild 10°C (50°F) at night to a hot 34°C (93°F) during the day, with an average temperature of 20°C (69°F). This month sees considerable precipitation, with about 146 mm (5.7 in) of rain spread over 19 days, resulting in a humidity level of 81%. In stark contrast, July features much cooler conditions, with minimum temperatures dropping to -4°C (25°F) and a maximum of 25°C (78°F), averaging around 10°C (51°F). Precipitation is minimal in July, totaling just 2 mm (0.1 in) and recorded on no days, accompanied by a lower humidity of 71%. For more detailed weather insights, you can visit Johannesburg weather in July.
When comparing the weather in December and August, it's clear that they present contrasting climates. December features much warmer temperatures, with a minimum of 10°C (50°F) and a maximum of 34°C (93°F), along with higher humidity at 81%. This month also experiences significant rainfall, averaging 146 mm (5.7 in) over 19 days. In stark contrast, August brings cooler weather with temperatures ranging from a minimum of -1°C (30°F) to a maximum of 27°C (80°F), along with a much drier atmosphere, receiving only 3 mm (0.1 in) of precipitation across the month and having no rainy days. For a more detailed look at Johannesburg's weather in August, you can visit Johannesburg weather in August.
When comparing the weather in December and September, notable differences emerge. December features a significantly warmer climate, with temperatures ranging from a minimum of 10°C (50°F) to a maximum of 34°C (93°F) and an average of 20°C (69°F). In contrast, September experiences much cooler conditions, with temperatures ranging from -1°C (31°F) to 32°C (91°F), and an average temperature of 17°C (64°F). Additionally, December sees higher precipitation, with 146 mm (5.7 in) over 19 days, compared to September's minimal 8 mm (0.3 in) across just 2 days. Humidity is also higher in December at 81%, compared to 74% in September. For more detailed information, visit Johannesburg weather in September.
December weather in Johannesburg exhibits a warmer climate compared to October. The minimum temperature in December is significantly higher at 10°C (50°F), with average highs reaching 34°C (93°F). In contrast, October experiences a cooler minimum temperature of 4°C (40°F) and average highs of 33°C (92°F). Additionally, December sees more rainfall, with 146 mm (5.7 in) over 19 days, while October has only 63 mm (2.5 in) over 8 days. The humidity also increases in December to 81%, compared to October's 74%. For a closer look at October's weather specifics, check out Johannesburg weather in October.
In comparing the weather of December and November, December tends to be slightly warmer, with minimum temperatures of 10°C (50°F) compared to November's 4°C (40°F), while both months share the same maximum temperature of 34°C (93°F). The average temperature remains consistent at around 20°C (68°F to 69°F) for both months. However, December experiences a higher level of precipitation, with 146 mm (5.7 in) over 19 days, while November has less rainfall at 97 mm (3.8 in) over 13 days. Humidity is slightly lower in December at 81% compared to November's 82%. For more details, check Johannesburg weather in November.
As December unfolds in Johannesburg, the city's weather shines a spotlight on its vibrant summer season. With maximum temperatures soaring to a sweltering 34°C and an average of 20°C, the warmth invites both locals and visitors to enjoy outdoor festivities and lush green landscapes. However, it’s important to note that December also brings a fair share of rain, with 19 days experiencing precipitation, contributing to a high humidity level of 81%. This contrasts sharply with the drier, cooler months preceding it, making December a unique blend of warmth and humidity. For those interested in a deeper dive into Johannesburg's climate patterns, explore more at Johannesburg Climate.