Climate - Nosy Be (Madagascar)

In Nosy Be (or Nossi-bé), the climate is tropical, hot all year round, with a rainy, hotter season from November to April and a dry season from May to October.
The island is located off the northwest coast of Madagascar. In the austral summer, this area is affected by the hot and humid monsoon coming from the north-west, while in the austral winter, the cooler and drier south-east trade winds prevail. The climate of the neighbouring islands, such as Nosy Komba, Nosy Mitsio, Nosy Tanikely and Nosy Sakatia, is similar.
In the period that could be called winter, from June to September, the night temperature drops quite often below 20 °C (68 °F), and sometimes, it can even drop to around 15/16 °C (59/61 °F), but during the day, it's almost always warm, thanks to the winds that blow from the interior of Madagascar.
Here are the average temperatures.

In an average year, about 2,200 millimeters (86 inches) of rain fall. In the rainiest months (December, January and February), the rains are definitely frequent, in fact, they occur almost daily, and they can sometimes be torrential. On the contrary, at the height of the dry season, from June to September, rare showers occur, which become a bit more frequent in May and October.
Here is the average precipitation.

The amount of sunshine in Nosy Be is good from May to October, while it is acceptable in the rainiest months, from December to February, when, apart from showers and thunderstorms, the sun shines for a few hours a day. Here are the average sunshine hours per day.

From November to mid-May, Nosy Be may be affected by the tropical cyclones of the South-West Indian Ocean, which, in any case, are more common from January to March.



The sea in Nosy Be is warm enough to swim in all year round, since the water temperature ranges from 26 °C (79 °F) between July and October to 29 °C (84 °F) between January and April. Here are the average sea temperatures.

Best Time

The best time to go to Nosy Be goes from mid-May to October. In the first half of May, usually, the weather is already good, but there is still some risk, though low, of tropical cyclones, as happened with cyclone Kesiny, which affected this area around May 10, 2002.

Nosy Be - Weather by month

Based on the period 1991-2020

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In January, the weather in Nosy Be is usually very hot and muggy. The average temperature is of 28.0 °C (82 °F), with a minimum of 23.9 °C (74.9 °F) and a maximum of 32.1 °C (89.7 °F).
On the coldest nights of the month, the temperature usually drops to around 22.5 °C (72 °F).
On the warmest days of the month, the temperature usually reaches around 34 °C (93.5 °F).
Precipitation amounts to 465 mm (18.3 in), distributed over 20 days.
The day lasts on average 12 hours and 50 minutes.
There are on average 6 hours of sunshine per day. So, the sun shines 47% of the time.
The average humidity is 81%. Hence, the air is normally humid.
The average wind speed is 7 kph (5 mph).
The average sea temperature is of 29 °C (84 °F). Therefore, the sea is pleasantly warm and allows long swims.

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In February, the weather in Nosy Be is usually very hot and muggy. The average temperature is of 27.9 °C (82 °F), with a minimum of 23.8 °C (74.9 °F) and a maximum of 32 °C (89.6 °F).
On the coldest nights of the month, the temperature usually drops to around 22.5 °C (72 °F).
On the warmest days of the month, the temperature usually reaches around 34.5 °C (94 °F).
Precipitation amounts to 425 mm (16.7 in), distributed over 16 days.
The day lasts on average 12 hours and 30 minutes.
There are on average 6 hours of sunshine per day. So, the sun shines 48% of the time.
The average humidity is 81%. Hence, the air is normally humid.
The average wind speed is 7 kph (4 mph).
The average sea temperature is of 29 °C (84 °F). Therefore, the sea is pleasantly warm and allows long swims.

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In March, the weather in Nosy Be is usually very hot and muggy. The average temperature is of 28.2 °C (83 °F), with a minimum of 23.8 °C (74.9 °F) and a maximum of 32.5 °C (90.5 °F).
On the coldest nights, the temperature usually drops to around 20.5 °C (69 °F).
On the warmest days, the temperature usually reaches around 34.5 °C (94 °F).
Precipitation amounts to 285 mm (11.2 in), distributed over 13 days.
The day lasts on average 12 hours and 5 minutes.
There are on average 7 hours of sunshine per day. So, the sun shines 60% of the time.
The average humidity is 79%. Hence, the air is normally humid.
The average wind speed is 6 kph (4 mph).
The average sea temperature is of 29 °C (84.5 °F). Therefore, the sea is pleasantly warm and allows long swims.

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In April, the weather in Nosy Be is usually very hot and muggy. The average temperature is of 28.2 °C (83 °F), with a minimum of 23.6 °C (74.4 °F) and a maximum of 32.8 °C (91 °F).
On the coldest nights, the temperature usually drops to around 21.5 °C (71 °F).
On the warmest days, the temperature usually reaches around 34.5 °C (93.5 °F).
Precipitation amounts to 140 mm (5.5 in), distributed over 7 days.
The day lasts on average 11 hours and 50 minutes.
There are on average 8 hours of sunshine per day. So, the sun shines 69% of the time.
The average humidity is 75%. Hence, the air is normally humid.
The average wind speed is 6 kph (4 mph).
The average sea temperature is of 29 °C (84.5 °F). Therefore, the sea is pleasantly warm and allows long swims.

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In May, the weather in Nosy Be is usually warm to hot and muggy. The average temperature is of 27.0 °C (81 °F), with a minimum of 21.9 °C (71.5 °F) and a maximum of 32.1 °C (89.8 °F).
On the coldest nights, the temperature usually drops to around 18 °C (64.5 °F).
On the warmest days, the temperature usually reaches around 34.5 °C (94 °F).
Precipitation amounts to 60 mm (2.4 in), distributed over 3 days.
The day lasts on average 11 hours and 30 minutes.
There are on average 9 hours of sunshine per day. So, the sun shines 76% of the time.
The average humidity is 72%. Hence, the air is normally humid.
The average wind speed is 6 kph (4 mph).
The average sea temperature is of 28.5 °C (83.5 °F). Therefore, the sea is pleasantly warm and allows long swims.

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In June, the weather in Nosy Be is usually warm to hot. The average temperature is of 25.8 °C (78 °F), with a minimum of 20.4 °C (68.8 °F) and a maximum of 31.2 °C (88.1 °F).
On the coldest nights, the temperature usually drops to around 17 °C (63 °F).
On the warmest days, the temperature usually reaches around 33 °C (91.5 °F).
Precipitation amounts to 50 mm (2 in), distributed over 3 days.
The day lasts on average 11 hours and 25 minutes.
There are on average 8.5 hours of sunshine per day. So, the sun shines 73% of the time.
The average humidity is 70%.
The average wind speed is 7 kph (4 mph).
The average sea temperature is of 27 °C (81 °F). Therefore, the sea is pleasantly warm and allows long swims.

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In July, the least warm month of the year, the weather in Nosy Be is usually warm to hot. The average temperature is of 25.1 °C (77 °F), with a minimum of 19.5 °C (67 °F) and a maximum of 30.7 °C (87.2 °F).
On the coldest nights of the month, the temperature usually drops to around 16.5 °C (61.5 °F).
On the warmest days of the month, the temperature usually reaches around 33 °C (91.5 °F).
Precipitation amounts to 35 mm (1.4 in), distributed over 3 days.
The day lasts on average 11 hours and 25 minutes.
There are on average 8.5 hours of sunshine per day. So, the sun shines 75% of the time.
The average humidity is 67%.
The average wind speed is 7 kph (4 mph).
The average sea temperature is of 26 °C (79 °F). Therefore, the sea is warm enough for swimming.

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In August, the weather in Nosy Be is usually warm to hot. The average temperature is of 25.4 °C (78 °F), with a minimum of 19.6 °C (67.3 °F) and a maximum of 31.2 °C (88.1 °F).
On the coldest nights of the month, the temperature usually drops to around 16.5 °C (61.5 °F).
On the warmest days of the month, the temperature usually reaches around 33 °C (91 °F).
Precipitation amounts to 40 mm (1.6 in), distributed over 3 days.
The day lasts on average 11 hours and 40 minutes.
There are on average 9 hours of sunshine per day. So, the sun shines 79% of the time.
The average humidity is 64%.
The average wind speed is 8 kph (5 mph).
The average sea temperature is of 25.5 °C (78 °F). Therefore, the sea is warm enough for swimming.

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In September, the weather in Nosy Be is usually warm to hot. The average temperature is of 26.0 °C (79 °F), with a minimum of 20.2 °C (68.4 °F) and a maximum of 31.8 °C (89.3 °F).
On the coldest nights, the temperature usually drops to around 17.5 °C (64 °F).
On the warmest days, the temperature usually reaches around 33.5 °C (92.5 °F).
Precipitation amounts to 40 mm (1.6 in), distributed over 3 days.
The day lasts on average 12 hours and 0 minutes.
There are on average 9.5 hours of sunshine per day. So, the sun shines 77% of the time.
The average humidity is 62%.
The average wind speed is 8 kph (5 mph).
The average sea temperature is of 26 °C (78.5 °F). Therefore, the sea is warm enough for swimming.

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In October, the weather in Nosy Be is usually very hot. The average temperature is of 27.7 °C (82 °F), with a minimum of 22.2 °C (72 °F) and a maximum of 33.1 °C (91.6 °F).
On the coldest nights, the temperature usually drops to around 19 °C (66 °F).
On the warmest days, the temperature usually reaches around 35 °C (94.5 °F).
Precipitation amounts to 95 mm (3.7 in), distributed over 5 days.
The day lasts on average 12 hours and 25 minutes.
There are on average 9 hours of sunshine per day. So, the sun shines 73% of the time.
The average humidity is 61%.
The average wind speed is 9 kph (6 mph).
The average sea temperature is of 26.5 °C (79.5 °F). Therefore, the sea is pleasantly warm and allows long swims.

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In November, the hottest month of the year, the weather in Nosy Be is usually very hot. The average temperature is of 28.3 °C (83 °F), with a minimum of 23.2 °C (73.8 °F) and a maximum of 33.3 °C (91.9 °F).
On the coldest nights, the temperature usually drops to around 20.5 °C (69 °F).
On the warmest days, the temperature usually reaches around 35 °C (95.5 °F).
Precipitation amounts to 190 mm (7.5 in), distributed over 10 days.
The day lasts on average 12 hours and 40 minutes.
There are on average 8.5 hours of sunshine per day. So, the sun shines 66% of the time.
The average humidity is 66%.
The average wind speed is 8 kph (5 mph).
The average sea temperature is of 27.5 °C (81.5 °F). Therefore, the sea is pleasantly warm and allows long swims.

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In December, the hottest month of the year, the weather in Nosy Be is usually very hot and muggy. The average temperature is of 28.0 °C (82 °F), with a minimum of 23.6 °C (74.5 °F) and a maximum of 32.4 °C (90.3 °F).
On the coldest nights of the month, the temperature usually drops to around 21 °C (70 °F).
On the warmest days of the month, the temperature usually reaches around 34 °C (93.5 °F).
Precipitation amounts to 360 mm (14.2 in), distributed over 14 days.
The day lasts on average 12 hours and 55 minutes.
There are on average 7 hours of sunshine per day. So, the sun shines 55% of the time.
The average humidity is 76%. Hence, the air is normally humid.
The average wind speed is 7 kph (4 mph).
The average sea temperature is of 28.5 °C (83.5 °F). Therefore, the sea is pleasantly warm and allows long swims.