Climate Insights for Clanwilliam

The climate in Clanwilliam is temperate. The average annual temperature is 18°C and approximately 244mm of precipitation falls per year. June is the wettest month, receiving around 54mm of rainfall. Clanwilliam is in the Southern Hemisphere. The seasons are reversed — summer runs from December to February, while winter falls between June and August. The summer months are: February, January, December. The coldest months are August, July, June, when temperatures can drop to 6°C.

Temperatures in Clanwilliam vary considerably across the year, with a 24°C difference between the coldest and warmest months. The warmest month is February, when average highs reach 30°C and the mean temperature sits around 23°C. August is the coolest month, with minimum temperatures around 6°C and an average of 12°C. On average, daily temperatures fluctuate by about 13°C between overnight lows and afternoon highs. The sharpest temperature change occurs between May and June, with a 3°C shift in average temperatures.

Clanwilliam is a quite dry location, receiving approximately 244mm of precipitation annually, which averages out to around 20mm per month. The wettest month is June, averaging 54mm of rainfall. July and August also tend to see above-average precipitation. The driest month is February, with just 4mm. That's 50mm less than June, the wettest month. Rainfall is heavily concentrated in certain months, creating a distinct wet and dry season. Visitors should plan around these patterns, as the difference between peak and low months is dramatic.

Clanwilliam is relatively calm, with an average annual wind speed of 3km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is November, averaging 3km/h, though still comfortable for most outdoor activities. The calmest conditions occur in May, with average winds dropping to 2km/h, making it an ideal period for wind-sensitive activities. There is moderate seasonal variation in wind speed, with a 1km/h gap between the calmest and windiest months.

It is currently autumn in Clanwilliam, which began on March 20, 2026. Clanwilliam is in the Southern Hemisphere, where the seasons are reversed — spring starts in September, summer in December, autumn in March, and winter in June. The warmest period peaks in February at around 30°C, while the coldest stretch bottoms out in August near 6°C. Winter is next, beginning on June 21, 2026 — 3 days from now.

The best time to visit Clanwilliam is during January, February, March, April, May, October, November and December, when the weather is most comfortable for travellers. During these months, average temperatures hover around 20°C with modest rainfall averaging 12mm per month. By contrast, August can be quite cold with temperatures dropping to 6°C. With minimal rainfall expected, you can pack light and plan outdoor activities with confidence.

The table below shows monthly climate averages for Clanwilliam based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.