Weather in Zanzibar in August

Prime time. August is about as good as Zanzibar gets. Highs average 27.2 °C, lows 24.2 °C, and rain falls on 4 days — nothing in the month is working against you.

August ranks 2 of 12 in Zanzibar. Only July scores clearly higher, and the difference is small enough to be settled by price rather than weather.

Rain falls on only 4 days, so an itinerary with no wet-weather fallback is a reasonable risk. Nothing specialised needed — this is the month you pack for the trip rather than for the weather.

What the averages hide

Averages flatten a month, and this one hides a few things: it never really gets hot: not one day in an average August reaches 30 °C; the day barely swings — 3 °C between the overnight low and the afternoon high. Across the twenty years measured, the hottest August day reached 28.4 °C and the coldest night fell to 22.8 °C.

August is moderately variable: 5 mm in the driest year against 28 mm in the wettest, around an average of 14 mm. Roughly two Augusts in three land near that average, and the third does something else entirely.

Wind sits around 19.8 km/h — a steady breeze rather than a nuisance, and welcome on the warmer days, and humidity is unremarkable at 74%.

How August sits in the year

Temperatures hold steady either side: 27 °C in July, 27.2 here, 27.8 in September. Nothing about the timing within the month matters much.

Daylight in August

Zanzibar sits close enough to the equator that daylight barely moves all year — 11.9 hours in August, against a range of just 0.7 hours across the whole calendar. Sunrise and sunset land at roughly the same time whenever you come.

Sea temperature

The sea sits at about 25.6 °C in August — warm enough to stay in as long as you like. The sea peaks at 29.5 °C in March and bottoms out at 25.6 °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

Peak season. Expect the highest prices of the year and to be booking well ahead.

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

August in Zanzibar versus nearby

If Zanzibar is one option among several, the nearby comparison is worth making. Dar es Salaam is close enough to be a coin toss — within a degree on temperature, the same number of rain days. Mombasa is the weaker option in August — 3.4 °C warmer, 4 days more rain.

So: August is effectively as good as it gets here — 1 points behind July, which is inside the margin where the weather stops being the deciding factor and price starts being it.

Every month in Zanzibar

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