Zanzibar weather in four lines
- It is hot all year. Twenty eight to thirty three degrees by day, every month, and the sea never drops below twenty five.
- Two rainy seasons, and they are different. The long rains in April and May genuinely disrupt a trip. The short rains in November are afternoon showers.
- The wind decides more than the rain. The kusi from June to September is what makes those months dry, breezy and busy.
- Humidity is the real variable. February is the hottest month and July the most comfortable, despite only five degrees between them.
Pick a month
Temperature, sea, rainfall, sunshine and how busy it gets, with a verdict for the beach, for diving and for kitesurfing. The figures are seasonal averages, so read the shape rather than the decimal.
Zanzibar weather in January
BusyThe warm window
Air (day / night)
32° / 24°
Sea
28°
Rain
65 mm
~8 days
Sunshine
8 h/day
In short
Hot and bright, sea at 28 degrees, with short showers that clear as fast as they arrive.
Our advice
A good gap between the two rainy spells. Book early, the festive high season still has hold of it.
Zanzibar weather in February
BusyThe warm window, and the driest of the southern summer
Air (day / night)
33° / 24°
Sea
29°
Rain
55 mm
~6 days
Sunshine
8 h/day
In short
The hottest month and one of the driest. Calm sea at 29 degrees and the best underwater visibility of the summer.
Our advice
The best trade off between heat, sea and clear sky before the long rains. This is the month for Mnemba and Pemba.
Zanzibar weather in March
ModerateThe long rains begin, Masika
Air (day / night)
32° / 24°
Sea
29°
Rain
145 mm
~12 days
Sunshine
7 h/day
In short
The weather turns during the month. Early March still holds, late March does not.
Our advice
The first two weeks are usable. Keep the plan loose, because the water clouds up in places.
Zanzibar weather in April
QuietThe long rains at their peak
Air (day / night)
30° / 23°
Sea
29°
Rain
380 mm
~18 days
Sunshine
5 h/day
In short
The wettest month of the year: rain most days, grey skies, rough sea and poor visibility underwater.
Our advice
Avoid it for a beach trip. In exchange, prices bottom out and the sites are empty.
Zanzibar weather in May
QuietThe long rains easing
Air (day / night)
29° / 22°
Sea
28°
Rain
290 mm
~16 days
Sunshine
6 h/day
In short
Still wet, but the trend is downward, especially in the last week. Almost nobody about.
Our advice
Late May the weather picks up slowly. A real budget option if you accept the risk of losing days.
Zanzibar weather in June
ModerateThe dry season starts
Air (day / night)
29° / 21°
Sea
27°
Rain
55 mm
~8 days
Sunshine
8 h/day
In short
Dry weather returns, the air is softer and the south east trade winds get up. The kite season restarts.
Our advice
One of the best value months of the year: dry, pleasant, without July's crowds or July's prices.
Zanzibar weather in July
BusyDry season, high season
Air (day / night)
28° / 20°
Sea
26°
Rain
45 mm
~7 days
Sunshine
8 h/day
In short
Dry and sunny, cooler than the summer, with steady wind. This is the peak of the kitesurf season at Paje and Jambiani.
Our advice
Bring something warm for the evenings. Book hotels and boat trips months ahead.
Zanzibar weather in August
BusyDry season, high season
Air (day / night)
28° / 20°
Sea
25°
Rain
40 mm
~7 days
Sunshine
8 h/day
In short
The driest and windiest month, with the sea a little cooler at 25 degrees. Kiting at its best, beaches at their busiest.
Our advice
The most reliable weather of the year. It is also the fullest, so lock everything in early.
Zanzibar weather in September
ModerateDry season
Air (day / night)
29° / 21°
Sea
25°
Rain
50 mm
~8 days
Sunshine
9 h/day
In short
Dry, very sunny, the sea warming again and diving visibility coming back.
Our advice
The window for avoiding the summer crowds without giving up the weather.
Zanzibar weather in October
ModerateThe end of the dry season
Air (day / night)
30° / 22°
Sea
26°
Rain
90 mm
~10 days
Sunshine
9 h/day
In short
Hot, dry and bright, with a calm sea and excellent visibility underwater before the short rains.
Our advice
One of the best diving months at Mnemba. Book before the festive season pushes prices up.
Zanzibar weather in November
QuietThe short rains, Vuli
Air (day / night)
31° / 23°
Sea
27°
Rain
210 mm
~14 days
Sunshine
8 h/day
In short
Passing showers, often late in the day, between long clear spells. Nothing like April.
Our advice
Unreliable rather than ruinous, and the prices are soft. Have a plan B for the heavy afternoons.
Zanzibar weather in December
BusyThe short rains end, then the holidays
Air (day / night)
32° / 24°
Sea
28°
Rain
130 mm
~12 days
Sunshine
8 h/day
In short
Hot, with the rain thinning out through the month, a warm sea at 28 degrees and a festive mood by Christmas.
Our advice
Holiday high season: hotels full and prices peaking from about 20 December to 5 January. Book very early.
Indicative seasonal averages for Unguja, the main island. Real figures move from one year to the next, so the point is the shape of the seasons rather than the decimal. For an actual forecast, use a forecasting service.
Zanzibar weather by month
Temperatures barely move here. What changes is the rain and the wind, and those are what decide a month.
| Month | Daytime | Rain | Sea | Verdict |
|---|---|---|---|---|
| January | 32°C | Low | 29°C | Hot, humid, busy. Good. |
| February | 33°C | Low | 29°C | The hottest and among the best. Flat sea, best visibility. |
| March | 33°C | Rising | 29°C | Still good early, deteriorating fast at the end. |
| April | 31°C | Heavy | 28°C | The long rains. Avoid unless price is everything. |
| May | 30°C | Heavy | 27°C | Still wet, clearing late. Cheapest month of the year. |
| June | 29°C | Low | 26°C | Dry, breezy, cooler. High season starts. |
| July | 28°C | Low | 25°C | Coolest and windiest. Peak kusi for kitesurfing. |
| August | 28°C | Low | 25°C | Busy, windy, dry. The European holiday month. |
| September | 29°C | Low | 26°C | Dry, calmer, and quieter than August. Underrated. |
| October | 30°C | Rising | 27°C | Warm, flat sea, and the short rains arriving late. |
| November | 31°C | Moderate | 28°C | Short rains, mostly afternoon showers. Good value. |
| December | 32°C | Falling | 28°C | Wet early, superb by Christmas, and priced accordingly. |
The rain is not the British kind. Even in the wet months it usually arrives as a heavy afternoon downpour rather than an overcast day. Read when to go to Zanzibar for the month by month verdict.
The four seasons that actually exist here
Swahili has names for them, and they are more useful than the European vocabulary because they describe wind and rain rather than temperature. The temperature barely moves all year.
January and February
Kaskazi
The warm window
The north east monsoon. Hot, humid, with short sharp showers that pass. The sea reaches 29 degrees and the underwater visibility is at its best of the southern summer.
March to May
Masika
The long rains
The one season worth planning around. April is the wettest month of the year, with rain most days, grey skies and a rough sea. Prices collapse, and so does the beach holiday.
June to September
Kipupwe
The dry, cooler season
The south east trade winds, dry air and the most reliable weather of the year. Cooler nights, a sea down at 25 degrees in August, and the peak of the kite season.
October to December
Vuli
The short rains
Passing afternoon showers rather than days of rain. October is dry and excellent. November is unpredictable and cheap. December dries out as the holidays approach.
The two rainy seasons are not the same thing
This is the confusion that costs people a holiday. A booking site will tell you November and April are both wet, and leave it there. On the ground they are barely comparable.
November brings around 210 millimetres over fourteen days, usually as an afternoon downpour that clears by evening. You lose an hour, not a day, and you pay low season rates for the privilege.
April brings 380 millimetres over eighteen days, with heavy cloud between the showers, a sea churned up enough to close the boat tripsand visibility underwater that makes diving pointless. Some hotels simply shut.
The sea is warm all year, and that is the point
Between 25 and 29 degrees, twelve months a year. There is no month where the water is a reason to stay out of it, which is unusual and is a large part of why the island works as a destination whenever you can get away.
What does change is what the water is doing. The trade winds of July and August put chop on the surface and make the diving harder while making the kitesurfing world class. February and October give you glass and the visibility that goes with it.
Questions people ask
What is the rainiest month in Zanzibar?
April, by a distance. It averages around 380 millimetres across roughly eighteen rainy days, against forty in August. March and May are wet too, but April is the month where a beach holiday stops working.
Is Zanzibar hot all year round?
Yes, and the variation is small. Daytime highs run from 28 degrees in August to 33 in February, and the sea never drops below 25. What changes through the year is the rain and the wind, not the temperature.
When is the sea warmest in Zanzibar?
February and March, at about 29 degrees. The coolest is August at 25, which is still warmer than the Mediterranean in summer. Nobody has ever needed a wetsuit here for comfort.
Does it rain all day during the rainy season?
It depends which rainy season. During the short rains of November and December, showers are usually an hour or two in the afternoon and the rest of the day is fine. During the long rains of April, it can rain for most of the day for several days in a row.