Last updated: August 31, 2025
September in Johannesburg, South Africa marks the transition into the spring season, showcasing a delightful blend of sunny days and cooler evenings. With maximum temperatures soaring to 32°C (91°F), the city invites outdoor activities and exploration, while the average temperature rests at a comfortable 17°C (64°F). Notably, nighttime can bring a brisk chill, with temperatures dipping to a minimum of -1°C (31°F). Rainfall is light, with only 8 mm (0.3 in) accumulated over just 2 days, and humidity levels hovering around 74%. Overall, September offers a refreshing climate, perfect for enjoying the vibrant culture and beautiful landscapes of Johannesburg.
As September rolls into Johannesburg, the city begins to shake off the winter chill, presenting a delightful transition in temperatures. With minimums around -1°C (31°F), brisk mornings give way to pleasantly warm afternoons, where averages reach around 17°C (64°F). Meanwhile, the maximum temperature can soar to an impressive 32°C (91°F), inviting locals and travelers alike to bask in the sun. This month marks a noticeable shift from the colder winter months, as daily temperatures start to climb, setting the stage for the vibrant spring season ahead. The combination of mild lows and warm highs makes September a fantastic time to explore the city's outdoor wonders and enjoy its lively atmosphere.
In September, Johannesburg sees a noticeable uptick in precipitation as spring begins to emerge, with an average rainfall of 8 mm (0.3 in) recorded over 2 days. This marks a slight increase compared to the preceding winter months, which were characterized by their minimal rainfall, reaching only 6 mm in June and 2 mm in July. As the city transitions into October, the precipitation significantly surges to 63 mm (2.5 in), showcasing the onset of the rainy season. This trend highlights Johannesburg's climatic shift from the dry winter months towards a more humid and vibrant spring, setting the stage for the lush greenery that follows in the later months of the year.
In September, Johannesburg enjoys a refreshing shift in humidity, with levels averaging 74%. This marks a gradual decrease from the peak of 82% observed in May and continues the trend of lower humidity that starts in mid-year. After the drier months of June and July, where humidity plummeted to 71% and 73% respectively, September brings a mild resurgence, balancing comfort with a hint of crispness in the air. This transitional month sets the stage for the warmer spring that follows, indicating a gentle return to the higher humidity levels typical of the later months in the year. Overall, September's climate is a refreshing prelude to the more humid days that characterize Johannesburg in the summer.
As September unfolds in Johannesburg, the UV Index reaches a notable 11, categorizing it as extreme. This marks a continuation of high UV exposure seen throughout the winter months, as the city transitions into spring. Despite the decline from winter’s UV readings, the burn time remains a swift 10 minutes, encouraging locals and visitors alike to prioritize sun protection. This trend suggests that even as temperatures warm, vigilance against UV radiation is crucial, echoing the extreme levels recorded in the preceding summer months. As always, staying informed is key to enjoying the outdoors safely—check out the comprehensive guide on the Johannesburg UV Index for further insights.
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As September unfolds in Johannesburg, the city basks in a delightful 337 hours of sunshine, marking a transition to the warmer months ahead. This month showcases a noticeable uptick in daylight compared to the winter months, where June's 298 hours felt rather subdued. With each passing month, the city has been steadily drenched in sun, peaking at 371 hours by December. September's brightness not only represents a hopeful sign of the approaching summer but also serves as a reminder of nature's rhythm, as it follows August's 329 hours, creating an inviting atmosphere for both locals and visitors alike. The steady increase through spring hints at the vibrant energy that Johannesburg will radiate as it progresses toward its sun-drenched summer peak.
In September, Johannesburg basks in the afterglow of winter, with a 78% chance of sunny weather. This marks a slight decrease from the peak sunny days of July, which boasts a remarkable 95%. As the city transitions from winter to spring, the likelihood of sunshine begins to decrease gradually during the next few months before hitting its yearly low in December. The trend clearly indicates that while September may see a dip in the sunshine odds compared to the colder months, it remains a delightful time for outdoor activities, as the promise of clear skies and pleasant temperatures beckon residents and visitors alike to enjoy the vibrant beginnings of spring.
As September unfolds in Johannesburg, daylight begins to extend its embrace, marking a subtle shift in the seasonal rhythm. With 11 hours of daylight, the month mirrors both August and April, suggesting a balance between the lingering coolness of winter and the approaching warmth of spring. This gradual increase in daylight hours is a precursor to the radiant 12 hours found in October, setting the stage for longer, sun-kissed days ahead. In the broader context, September acts as a bridge, where the daylight duration is reinvigorated after the winter months, hinting at the vitality and brightness that the summer will soon bring. The days lengthen steadily, inviting both nature and residents to awaken and thrive in the enriched daylight.
As September rolls into Johannesburg, the gentle breezes signify the transition from winter to spring, with an average wind speed of 3.7 m/s (8 mph). This month showcases a slight increase compared to the previous winter months, where the wind largely hovered around 2.9 m/s (6-7 mph). With the fresh gusts seen in late August carrying over, September's winds bring a sense of rejuvenation and anticipation. Looking ahead, the wind speeds are set to rise even further in October and November, peaking at 4.2 m/s (9 mph), ushering in a vibrant atmosphere as the city begins to bloom. Johannesburg's winds during this time reflect not just a change in climate but also an invitation to embrace the joys of spring.
Weather in Johannesburg varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Johannesburg, focusing on differences in temperature, rainfall, humidity, and UV levels.
In September, Johannesburg experiences a more moderate climate with temperatures ranging from a chilly minimum of -1°C (31°F) to a pleasant average of 17°C (64°F), peaking at a warm 32°C (91°F). The precipitation is minimal, with only about 8 mm (0.3 in) falling over two days and humidity averaging 74%. In contrast, January brings warmer temperatures, with a minimum of 9°C (48°F) and an average of 20°C (69°F), reaching a maximum of 33°C (92°F). However, it also sees a significant increase in rainfall, totaling 130 mm (5.1 in) across 14 days, along with a slight rise in humidity to 79%. For more detailed information, check out Johannesburg weather in January.
September and February showcase distinct weather patterns and temperatures. In September, temperatures range from a chilly minimum of -1°C (31°F) to a warm average of 17°C (64°F) and can peak at 32°C (91°F). The month sees relatively low precipitation, totaling just 8 mm (0.3 in) over about 2 days, with humidity levels around 74%. In contrast, February offers milder temperatures, with minimums of 10°C (51°F) and an average of 20°C (68°F), peaking at 31°C (87°F). However, it experiences significantly higher rainfall, accumulating 138 mm (5.4 in) over approximately 16 days, with humidity rising to 77%. For more detailed insights, you can check this link: Johannesburg weather in February.
September and March display notable differences in weather patterns. In September, temperatures range from a chilly minimum of -1°C (31°F) to a warm maximum of 32°C (91°F), with an average of 17°C (64°F) and only 8 mm (0.3 in) of precipitation over just 2 days. In contrast, March boasts milder conditions, with minimum temperatures starting at 8°C (46°F) and a higher average of 19°C (66°F). However, it also brings more rainfall, with precipitation totaling 79 mm (3.1 in) spread across 10 days. The humidity levels are slightly higher in March at 77%, compared to September’s 74%. For more detailed information, you can check out Johannesburg weather in March.
When comparing the weather in September and April, notable differences can be observed. September experiences a wider temperature range, with minimums dipping to -1°C (31°F) and maximums reaching up to 32°C (91°F), while April has milder temperatures ranging from 3°C (38°F) to a maximum of 29°C (85°F). Moreover, April sees significantly higher precipitation, totaling 63 mm (2.5 in) over 10 days, compared to September's mere 8 mm (0.3 in) over just 2 days. Humidity levels are also slightly higher in April at 81%, compared to September's 74%. For more detailed information about April weather, you can refer to Johannesburg weather in April.
In comparing the weather in September and May, we observe some notable differences. September experiences a broader range of temperatures, with minimums dropping to -1°C (31°F) and maximums reaching up to 32°C (91°F), often leading to more comfortable average temperatures of 17°C (64°F). In contrast, May has a cooler average, with temperatures ranging from a minimum of -1°C (30°F) to a maximum of 26°C (78°F), resulting in an average of 13°C (56°F). When it comes to precipitation, September is drier with only 8 mm (0.3 in) over two days, while May sees slightly more rain at 13 mm (0.5 in) but over just one day. Notably, humidity levels are higher in May at 82% compared to 74% in September, contributing to the overall comfort levels in each month. For further details on weather in May, you can visit Johannesburg weather in May.
When comparing the weather in September and June, it is evident that September is significantly warmer, with average temperatures reaching 17°C (64°F) compared to June's average of 11°C (51°F). While September can experience a maximum of 32°C (91°F) and even dips to a minimum of -1°C (31°F), June sees its temperatures ranging from a chilly -4°C (24°F) at night up to a maximum of 24°C (76°F). Precipitation is slightly higher in September, with 8 mm (0.3 in) over two days, compared to June's 6 mm (0.2 in) over a single day. Both months share similar humidity levels, with September at 74% and June at 73%. For detailed insights into June weather, refer to Johannesburg weather in June.
September weather in Johannesburg is generally warmer than in July, with average temperatures soaring to 17°C (64°F), while July's average lingers at a cooler 10°C (51°F). September also experiences a broader temperature range, with minimum temperatures reaching as low as -1°C (31°F) and maximums climbing up to 32°C (91°F). In contrast, July's temperatures see a minimum of -4°C (25°F) and a maximum of only 25°C (78°F). Precipitation is slightly higher in September, with 8 mm (0.3 in) measured over two days, compared to July's virtually dry conditions with just 2 mm (0.1 in) and no rainy days. Both months maintain a similar level of humidity, around 71-74%. For a closer look at July's climate, you can check Johannesburg weather in July.
September displays a notable shift in weather patterns compared to August. While both months start with a minimum temperature of -1°C (31°F), September boasts a significantly higher average temperature of 17°C (64°F) and a maximum of 32°C (91°F), compared to August's average of 14°C (57°F) and maximum of 27°C (80°F). Additionally, September sees a slight increase in humidity at 74%, compared to August’s 68%. Precipitation levels also rise, with September receiving 8 mm (0.3 in) over two days, whereas August remains dry with only 3 mm (0.1 in) recorded across the month, marking zero rainy days. For more information on August weather specifics, visit Johannesburg weather in August.
In September, the weather tends to be warm during the day, with average temperatures around 17°C (64°F) and maximums reaching up to 32°C (91°F). However, it can also drop to a chilly minimum of -1°C (31°F) at night, providing a stark contrast. Precipitation is minimal, with only 8 mm (0.3 in) recorded over just two days and humidity at a steady 74%.
In contrast, October sees slightly warmer average temperatures of 19°C (66°F) and peaks reaching 33°C (92°F). The month is significantly wetter, with a total precipitation of 63 mm (2.5 in) spread across eight days, maintaining the same humidity level of 74%. This change signals a shift towards more unstable weather as the season progresses. For more detailed information, you can check Johannesburg weather in October.
In September, the weather is characterized by a wide range of temperatures, with a minimum of -1°C (31°F) and a maximum of 32°C (91°F), offering an average of 17°C (64°F). The month sees relatively low precipitation, with only 8 mm (0.3 inches) spreading over just 2 days, and humidity levels around 74%. In contrast, November experiences milder temperatures, with a minimum of 4°C (40°F) and a maximum reaching 34°C (93°F), averaging 20°C (68°F). However, November is significantly wetter, recording 97 mm (3.8 inches) of rain over 13 days, along with higher humidity levels at 82%. For more details on November weather, visit Johannesburg weather in November.
September and December showcase stark differences in weather patterns. In September, temperatures range from a chilly minimum of -1°C (31°F) to a warm maximum of 32°C (91°F), with an average of 17°C (64°F). The month experiences minimal rainfall, with only 8 mm (0.3 in) over just 2 days, and a humidity level of 74%. In contrast, December sees a notable rise in temperatures, with a minimum of 10°C (50°F) and a maximum reaching 34°C (93°F), resulting in a warmer average of 20°C (69°F). However, December is significantly wetter, experiencing 146 mm (5.7 in) of precipitation over 19 days, alongside a slightly higher humidity level of 81%. For more detailed information, check out Johannesburg weather in December.
As September unfolds in Johannesburg, it ushers in a refreshing transition from the chill of winter to the warmth of spring. With maximum temperatures reaching a comfortable 32°C (91°F) and an average hovering around 17°C (64°F), the weather is pleasantly mild. While rain is infrequent, with only a couple of wet days and minimal precipitation, the humidity can rise to 74%, adding a slight stickiness to the air. This month is distinctively warmer and sunnier compared to the preceding winter months, making it an ideal time to enjoy the blossoming landscapes. For a deeper understanding of how Johannesburg's weather evolves throughout the year, explore the detailed insights in Johannesburg Climate.