Weather in Cape Town in August

How August compares

August is the 12th warmest month of the year in Cape Town and ranks 134th of 134 destinations we compare for August - see where else is hot in August. Against London's average high of 21.4°C in August, Cape Town is 4.9°C cooler by day and 3.8°C cooler at night.

Daytime and night-time in August

The typical August day in Cape Town peaks at 16.5°C, but that is an average: the warmest 10% of days reach 20.2°C or more. Roughly 1 in 125 days top 25°C. Nights average 9.7°C; one night in ten drops to 6.9°C or lower, so pack a layer for evenings - it is genuinely cool after dark. Between 1991 and 2020 the hottest August day here reached 26.0°C (1998-08-27) and the coldest night 3.5°C (2003-08-21).

Rain in August

Wet (more than 8 rainy days): about 10 days with 1 mm or more, 74 mm in total. Year to year it varies a lot - the wettest August was 2013 with 175 mm, the driest 1991 with 20 mm. Humidity averages 80%.

Sea temperature in August

The sea averages 14.3°C - too cold for most (under 18°c). Depending on the year it ranges from 13.4°C to 14.9°C. For the warmest sea here, come in February (18.4°C).

Sunshine and daylight

Around 5.8 hours of sunshine a day (estimated from cloud cover), 10.7 hours of daylight: the sun rises about 07:25 and sets about 18:16 local time in mid-August. Average cloud cover is 46%.

Is August a good time to visit Cape Town?

August is not the strongest month here: mild days and frequent rain. The best months for Cape Town on our scoring are February, January, March; months averaging 25°C or more: Jan, Feb.

Expect cooler days than a London August

August is Cape Town's coolest month by daytime temperature, with average highs below London's 21.4°C. That makes it better suited to being out and about in layers than sitting around in beachwear. Warmer spells do happen: the warmest 10% of days reach 20.2°C or more, but days reaching 25°C are rare. A light top may be comfortable during a warmer afternoon, though it should not be your only option. Pack trousers, a jumper and a jacket, especially for evenings. Average night lows of 9.7°C mean outdoor dinners can feel chilly, while the coldest nights call for something warmer than a thin cardigan.

Leave room to change plans around rain

Rain is a real consideration in August, with about 10 rainy days, so a tightly scheduled outdoor holiday is a poor fit. Keep weather-sensitive plans movable and have indoor alternatives rather than assuming every day will stay dry. A waterproof jacket and shoes that cope with wet conditions are sensible luggage choices. The catch is not constant gloom: August still averages about 5.8 hours of sunshine a day within 10.7 hours of daylight. That leaves scope for time outside, but sunshine is not a promise of an uninterrupted dry afternoon. Make use of brighter periods and allow yourself to rearrange plans.

Treat the sea as scenery, not a warm swim

The sea averages 14.3°C, firmly in the cold category, so August does not suit a holiday built around comfortable swimming. Its year-to-year range of 13°C to 15°C offers little reason to hope for warm water even in a milder year. You can still spend time by the coast, but dress for the air temperature and keep a warm layer handy rather than planning long stretches in swimwear. If you mainly want mild conditions for time outdoors and do not mind adjusting to showers, the month can work. If warm afternoons and easy sea swimming are priorities, the weather is a substantial compromise.