Climate averages 1991–2020
Heidelberg, South Africa weather
in December.
A warm, wet month: the joint 2nd warmest and the wettest of the year.
Long-term climate patterns, not a forecast for a particular trip.
December is a warm month in Heidelberg, South Africa: daytime highs average 25.7°C and nights cool to about 15.0°C. By daytime temperature it is the joint 2nd warmest of the 12 months.
Expect about 140 mm of rain on roughly 17 days, which makes December a wet month (the wettest month of the year). Daylight, from sunrise to sunset, lasts about 13 h 46 min on an average December day.
The nearest other city in this atlas is Nigel (14 km away). In December its highs average 25.3°C, about as warm as Heidelberg, South Africa, with 147 mm of rain.
Among the 95 cities listed in South Africa, Heidelberg, South Africa ranks 51st of 95 for the warmest December highs and joint 76th of 95 for the driest December (rainfall, lowest first). The mean December high of those 95 cities is 26.6°C; Heidelberg, South Africa is 1.0°C cooler than that mean.
From December to January, average highs stay level at 25.7°C, and monthly rainfall falls from 140 mm to 130 mm.
The annual picture
December 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 | 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, selected | 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
December in nearby cities
- Nigel in DecemberSouth Africa · 14 kmHigh 25.3°C · Low 14.7°C · 147 mm rain
- Tokoza in DecemberSouth Africa · 28 kmHigh 25.5°C · Low 14.9°C · 130 mm rain
- Brakpan in DecemberSouth Africa · 30 kmHigh 25.0°C · Low 14.4°C · 130 mm rain
- Alberton in DecemberSouth Africa · 35 kmHigh 25.4°C · Low 14.8°C · 138 mm rain
- Benoni in DecemberSouth Africa · 35 kmHigh 25.0°C · Low 14.5°C · 130 mm rain
- Germiston in DecemberSouth Africa · 38 kmHigh 25.1°C · Low 14.6°C · 130 mm rain
- Etwatwa in DecemberSouth Africa · 43 kmHigh 25.1°C · Low 14.7°C · 135 mm rain
- Johannesburg in DecemberSouth Africa · 46 kmHigh 24.3°C · Low 13.7°C · 138 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.