Climate averages 1991–2020
Heidelberg, South Africa weather
in September.
A warm, fairly dry month: the 6th warmest and the 5th driest of the year. Meets the pleasant-weather rule
Long-term climate patterns, not a forecast for a particular trip.
September is a warm month in Heidelberg, South Africa: daytime highs average 25.1°C and nights cool to about 9.8°C. By daytime temperature it is the 6th warmest of the 12 months.
Expect about 22 mm of rain on roughly 4 days, which makes September a fairly dry month (the 5th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 11 h 55 min on an average September day.
The nearest other city in this atlas is Nigel (14 km away). In September its highs average 24.8°C, about as warm as Heidelberg, South Africa, with 23 mm of rain.
Among the 95 cities listed in South Africa, Heidelberg, South Africa ranks joint 36th of 95 for the warmest September highs and joint 47th of 95 for the driest September (rainfall, lowest first). The mean September high of those 95 cities is 24.3°C; Heidelberg, South Africa is 0.8°C warmer than that mean.
From September to October, average highs rise by 0.8°C to 25.9°C, and monthly rainfall rises from 22 mm to 78 mm.
The annual picture
September in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Heidelberg, South Africa climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 25.7°C15.4°C | 15.4°C | 130 | 16.0 | 13.614 h |
| February | 25.5°C15.2°C | 15.2°C | 100 | 12.8 | 13.013 h |
| March | 24.3°C13.6°C | 13.6°C | 84 | 11.4 | 12.312 h |
| April | 22.0°C10.6°C | 10.6°C | 41 | 6.8 | 11.511 h |
| May | 19.9°C6.9°C | 6.9°C | 15 | 2.7 | 10.811 h |
| June | 17.6°C3.8°C | 3.8°C | 7.4 | 1.5 | 10.511 h |
| July | 17.8°C3.0°C | 3.0°C | 3.3 | 0.7 | 10.611 h |
| August | 21.0°C5.9°C | 5.9°C | 11 | 2.1 | 11.211 h |
| September, selected | 25.1°C9.8°C | 9.8°C | 22 | 3.6 | 11.912 h |
| October | 25.9°C12.3°C | 12.3°C | 78 | 10.5 | 12.713 h |
| November | 25.5°C13.5°C | 13.5°C | 101 | 13.8 | 13.413 h |
| December | 25.7°C15.0°C | 15.0°C | 140 | 16.9 | 13.814 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
September in nearby cities
- Nigel in SeptemberSouth Africa · 14 kmHigh 24.8°C · Low 9.6°C · 23 mm rain
- Tokoza in SeptemberSouth Africa · 28 kmHigh 24.9°C · Low 9.5°C · 23 mm rain
- Brakpan in SeptemberSouth Africa · 30 kmHigh 24.5°C · Low 9.3°C · 23 mm rain
- Alberton in SeptemberSouth Africa · 35 kmHigh 24.7°C · Low 9.5°C · 22 mm rain
- Benoni in SeptemberSouth Africa · 35 kmHigh 24.4°C · Low 9.2°C · 23 mm rain
- Germiston in SeptemberSouth Africa · 38 kmHigh 24.5°C · Low 9.3°C · 23 mm rain
- Etwatwa in SeptemberSouth Africa · 43 kmHigh 24.7°C · Low 9.7°C · 23 mm rain
- Johannesburg in SeptemberSouth Africa · 46 kmHigh 23.4°C · Low 8.5°C · 22 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Heidelberg) is explained once on the Heidelberg, South Africa year overview and on the Sources, method and limits page.