Cape Town Weather in September
South Africa · Mediterranean climate · Data averaged from 2020-01-01 to 2024-12-31 (5 years)
September in Cape Town sees average temperatures ranging from a low of 10.5°C (50.9°F) to a high of 17.5°C (63.5°F), with a mean of 13.8°C (56.8°F). Compared to the annual average of 16.8°C (62.2°F), this month is 3.0°C cooler than the yearly norm. Precipitation averages 56.2mm, making it approximately 3.0mm drier than the monthly average of 60.0mm. The city receives an average of 9.9 hours of sunshine per day during September, with relative humidity averaging 76.6%. Wind speeds reach an average maximum of 22.1 km/h. For travelers, this month offers a temperature experience in Cape Town, with drier-than-average conditions compared to the rest of the year.
Cape Town's climate data reveals a fascinating pattern: it's one of the few Southern Hemisphere cities with a true Mediterranean climate. I was there in January (their summer) expecting tropical heat — instead got dry, windy, 26°C days perfect for wine country visits. The data shows December-February as ideal, but watch for the 'Cape Doctor' — a strong southeast wind that can disrupt plans. Winter (June-August) is wet and cool, but the whale watching peaks in July.
September vs Adjacent Months
| Metric | August | September | October |
|---|---|---|---|
| Mean Temp | 12.8°C (55.0°F) | 13.8°C (56.8°F) | 16.9°C (62.4°F) |
| Rainfall | 108.9mm | 56.2mm | 26.2mm |
| Sunshine | 8.9 hrs | 9.9 hrs | 11.8 hrs |
| Humidity | 78.2% | 76.6% | 72.7% |
| Wind | 21.2 km/h | 22.1 km/h | 24.2 km/h |
| Rainy Days | 16.2 | 13.2 | 10.8 |
Seasonal Context
September falls in Autumn in the Northern Hemisphere. Autumn sees temperatures gradually cooling from summer highs. For travelers visiting Cape Town in September, the data indicates mixed conditions based on the combination of temperature, precipitation, and daylight hours.
Frequently Asked Questions
What is the average temperature in Cape Town in September?
The average temperature in Cape Town during September ranges from 10.5°C (50.9°F) to 17.5°C (63.5°F), with a mean of 13.8°C (56.8°F).
How much does it rain in Cape Town in September?
Cape Town receives an average of 56.2mm of precipitation in September, spread across approximately 13.2 rainy days.
What should I pack for Cape Town in September?
Based on September weather data, pack warm layers, a medium jacket, and waterproof outerwear.
Is September a good time to visit Cape Town?
September is a cooler month, suitable for travelers who prefer mild weather and fewer crowds. Pack warm layers and enjoy indoor attractions.
Other Months for Cape Town
Cities with Similar September Climate (Mediterranean)
Data Source: Open-Meteo historical archive (2020-01-01 to 2024-12-31). Daily measurements aggregated into monthly climate normals. Coordinates: -33.92°, 18.42°. Timezone: Africa/Johannesburg. Last updated: 2026-07-30.