Climate averages 1991–2020
Westonaria 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 Westonaria: daytime highs average 25.5°C and nights cool to about 15.1°C. By daytime temperature it is the joint 2nd warmest of the 12 months.
Expect about 141 mm of rain on roughly 18 days, which makes December a wet month (the wettest month of the year). Daylight, from sunrise to sunset, lasts about 13 h 45 min on an average December day.
The nearest other city in this atlas is Randfontein (16 km away). In December its highs average 24.7°C, 0.8°C cooler than Westonaria, with 141 mm of rain.
Among the 95 cities listed in South Africa, Westonaria ranks joint 54th of 95 for the warmest December highs and joint 78th of 95 for the driest December (rainfall, lowest first). The mean December high of those 95 cities is 26.6°C; Westonaria is 1.1°C cooler than that mean.
From December to January, average highs stay level at 25.5°C, and monthly rainfall falls from 141 mm to 132 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
Westonaria climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 25.5°C15.5°C | 15.5°C | 132 | 16.9 | 13.614 h |
| February | 25.2°C15.2°C | 15.2°C | 118 | 14.4 | 13.013 h |
| March | 23.9°C13.7°C | 13.7°C | 90 | 12.8 | 12.312 h |
| April | 21.6°C10.6°C | 10.6°C | 45 | 7.3 | 11.511 h |
| May | 19.5°C7.2°C | 7.2°C | 18 | 3.1 | 10.811 h |
| June | 17.1°C4.0°C | 4.0°C | 8.1 | 1.4 | 10.511 h |
| July | 17.2°C3.2°C | 3.2°C | 3.2 | 0.8 | 10.711 h |
| August | 20.4°C6.0°C | 6.0°C | 9.7 | 1.9 | 11.211 h |
| September | 24.6°C9.7°C | 9.7°C | 21 | 3.4 | 11.912 h |
| October | 25.7°C12.3°C | 12.3°C | 73 | 10.4 | 12.713 h |
| November | 25.4°C13.6°C | 13.6°C | 99 | 13.9 | 13.413 h |
| December, selected | 25.5°C15.1°C | 15.1°C | 141 | 18.4 | 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
- Randfontein in DecemberSouth Africa · 16 kmHigh 24.7°C · Low 14.3°C · 141 mm rain
- Soweto in DecemberSouth Africa · 22 kmHigh 24.9°C · Low 14.6°C · 141 mm rain
- Carletonville in DecemberSouth Africa · 25 kmHigh 26.2°C · Low 15.5°C · 136 mm rain
- Roodepoort in DecemberSouth Africa · 28 kmHigh 24.4°C · Low 13.9°C · 141 mm rain
- Krugersdorp in DecemberSouth Africa · 29 kmHigh 24.6°C · Low 14.1°C · 128 mm rain
- Evaton in DecemberSouth Africa · 31 kmHigh 26.1°C · Low 15.4°C · 139 mm rain
- Johannesburg in DecemberSouth Africa · 41 kmHigh 24.3°C · Low 13.7°C · 138 mm rain
- Randburg in DecemberSouth Africa · 43 kmHigh 25.4°C · Low 14.8°C · 117 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 Westonaria) is explained once on the Westonaria year overview and on the Sources, method and limits page.
Soweto, Roodepoort and Randfontein lie in the same rainfall cell, so their rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.