Weather in Zanzibar in May

How May compares

May is the 9th warmest month of the year in Zanzibar and ranks 41st of 134 destinations we compare for May - see where else is hot in May. Against London's average high of 16.6°C in May, Zanzibar is 11.1°C warmer by day and 16.0°C warmer at night.

Daytime and night-time in May

The typical May day in Zanzibar peaks at 27.7°C, but that is an average: the warmest 10% of days reach 29.0°C or more. About 99% of days top 25°C and 1 in 36 pass 30°C. Nights average 24.3°C; one night in ten drops to 23.6°C or lower, so pack a layer for evenings. Between 1991 and 2020 the hottest May day here reached 31.8°C (2003-05-09) and the coldest night 21.5°C (1993-05-15).

Rain in May

Wet (more than 8 rainy days): about 20 days with 1 mm or more, 151 mm in total. Year to year it varies a lot - the wettest May was 2017 with 369 mm, the driest 2004 with 18 mm. Humidity averages 83%.

Sea temperature in May

The sea averages 27.9°C - warm enough to swim (22°c+). Depending on the year it ranges from 27.5°C to 28.3°C. For the warmest sea here, come in March (29.0°C).

Sunshine and daylight

Around 5.3 hours of sunshine a day (estimated from cloud cover), 11.7 hours of daylight: the sun rises about 06:25 and sets about 18:15 local time in mid-May. Average cloud cover is 55%.

Is May a good time to visit Zanzibar?

It is a reasonable choice: hot days but expect showers. The best months for Zanzibar on our scoring are September, August, July; months averaging 25°C or more: Jan, Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov, Dec.

Warm enough for swimming, but humid

The heat is dependable: temperatures reach 25°C on 99% of days, while 30°C is uncommon. That makes May suitable if you want warm weather without particularly high daytime temperatures, although humidity of 83% can still make being active feel sticky. Choose loose, breathable clothing and leave room to rest during the warmest part of the day. Nights offer little cooling, so air conditioning is a useful accommodation feature to check before booking. The sea averages about 28°C, making swimming comfortable on temperature alone. Rain and conditions on the day still need to guide when you get into the water.

Plan around rain, not uninterrupted beach days

May is a wet choice, so a holiday built entirely around lying outdoors is a gamble. About 5.3 hours of sunshine within 11.7 hours of daylight leaves room for bright weather, but does not promise a clear stretch whenever you want it. Keep outdoor plans movable and pack lightweight rain protection rather than relying on an umbrella alone. The monthly figures cannot tell you when rain will fall, so avoid assuming it will be confined to a convenient part of the day. If your dates are flexible, September, August and July are better-rated choices for Zanzibar overall; May makes more sense when warmth matters more than reliable sunshine.