Weather in Cape Town in August

A good month. August is a solid month to be in Cape Town. Highs average 15.6 °C, lows 13 °C, and rain falls on 12 days — nothing in the month is working against you.

August ranks 12 of 12 — near the bottom of Cape Town's year. February is the month that works, and the swing between the two is 33 points, which is a different holiday rather than a slightly better one. Worth keeping in perspective: August is the weakest month of Cape Town's year and it is still a perfectly good one. The downside here is small.

Rain on 12 days, 2 of them heavy. Enough to need a plan B, not enough to need a plan around it. Pack for 15.6 °C days and 13 °C nights; the spread matters more here than any single number.

What the averages hide

Averages flatten a month, and this one hides a few things: the day barely swings — 2.7 °C between the overnight low and the afternoon high. Across the twenty years measured, the hottest August day reached 21.8 °C and the coldest night fell to 9.2 °C, and the wettest single day dropped 31 mm — roughly 41% of the month's rain in one day.

August is statistically steady but not small: the year-to-year variation is modest in relative terms, yet the wettest August on record still delivered 152 mm against 35 mm in the driest. In a month this wet, even a tame spread is a lot of rain in absolute terms — the 76 mm average is a reasonable planning figure, not a promise.

Wind sits around 18 km/h — a steady breeze rather than a nuisance, and welcome on the warmer days, and humidity runs at 79%, high enough to notice on the warm days without dominating them.

How August sits in the year

Temperatures hold steady either side: 15.8 °C in July, 15.6 here, 16.5 in September. Nothing about the timing within the month matters much.

Daylight in August

10.8 hours of daylight, gaining 0.9 hours across the month. That is between Cape Town's extremes of 14.4 and 9.9 hours, so days are long enough not to constrain the plan.

Sea temperature

The sea sits at about 16.5 °C in August — cold — a quick dip rather than a swim, and a wetsuit if you are in for longer. The sea peaks at 20.8 °C in February and bottoms out at 16.5 °C — water lags the air by a month or two, which is why the best swimming often comes after the best weather.

How busy it gets

Off season. The genuine off season: cheapest by a distance, with the caveat that some tours and restaurants close entirely.

Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.

August in Cape Town versus nearby

If Cape Town is one option among several, the nearby comparison is worth making. Gqeberha is a better bet in August — 3.8 °C warmer, 6 days less rain. Pietermaritzburg is a better bet in August — 8.2 °C warmer, 6 days less rain.

So: August is a compromise. February is 33 points better and is what Cape Town is actually like at its best — worth moving the trip for if that is possible, and worth adjusting expectations for if it is not.

Every month in Cape Town

See all twelve months in Cape Town, or where else to go in August.