, with a rainy season from late December to July and a dry season from August to November.
The city is the capital of the state of Maranhão and is located in the north-east of Brazil, on an island near the coast, the island of Upaon-açu (or São Luís). On the island there are also the cities of São José de Ribamar, Paço do Lumiar, and Raposa. In the area, there are branches of some rivers that flow into the sea, the main one being the Mearim River. To the east is the Lençóis Maranhenses National Park, characterized by a surreal landscape, where sand dunes rise over a lagoon.
The best time to visit São Luís is from August to November, being the driest and sunniest of the year.
. Here are the average temperatures.
January is generally a very hot, muggy month. The average temperature is of
28.1 °C, with a minimum of
24.8 °C and a maximum of
31.4 °C.

On the coldest nights of the month, the temperature usually drops to around
22.5 °C.

On the warmest days of the month, the temperature usually reaches around
33.5 °C.

Precipitation amounts to
245 mm, distributed over 13 days.
The day lasts on average 12 hours and 10 minutes.

There are on average 5 hours of sunshine per day. So, the sun shines 40% of the time.
The average humidity is 79%. Hence, the air is normally humid.
The average wind speed is of
14.2 kph.

The average sea temperature is of
28.1 °C. Therefore, the sea is pleasantly warm and allows long swims.
February is generally a very hot, muggy month. The average temperature is of
27.7 °C, with a minimum of
24.4 °C and a maximum of
31 °C.

On the coldest nights of the month, the temperature usually drops to around
22 °C.

On the warmest days of the month, the temperature usually reaches around
33 °C.

Precipitation amounts to
375 mm, distributed over 17 days.
The day lasts on average 12 hours and 10 minutes.

There are on average 4 hours of sunshine per day. So, the sun shines 33% of the time.
The average humidity is 82%. Hence, the air is normally humid.
The average wind speed is of
12.1 kph.

The average sea temperature is of
28.4 °C. Therefore, the sea is pleasantly warm and allows long swims.
March, the least warm month of the year, is generally a warm to hot, muggy month. The average temperature is of
27.5 °C, with a minimum of
24.3 °C and a maximum of
30.7 °C.

On the coldest nights of the month, the temperature usually drops to around
22.5 °C.

On the warmest days of the month, the temperature usually reaches around
32.5 °C.

Precipitation amounts to
430 mm, distributed over 23 days.
The day lasts on average 12 hours and 5 minutes.

There are on average 3.5 hours of sunshine per day. So, the sun shines 29% of the time.
The average humidity is 84%. Hence, the air is normally humid.
The average wind speed is of
10.5 kph.

The average sea temperature is of
28.5 °C. Therefore, the sea is pleasantly warm and allows long swims.
April is generally a very hot, muggy month. The average temperature is of
27.6 °C, with a minimum of
24.4 °C and a maximum of
30.9 °C.

On the coldest nights of the month, the temperature usually drops to around
22.5 °C.

On the warmest days of the month, the temperature usually reaches around
32.5 °C.

Precipitation amounts to
475 mm, distributed over 22 days.
The day lasts on average 12 hours and 0 minutes.

There are on average 4 hours of sunshine per day. So, the sun shines 32% of the time.
The average humidity is 84%. Hence, the air is normally humid.
The average wind speed is of
9.2 kph.

The average sea temperature is of
28.7 °C. Therefore, the sea is pleasantly warm and allows long swims.
May is generally a very hot, muggy month. The average temperature is of
28 °C, with a minimum of
24.5 °C and a maximum of
31.4 °C.

On the coldest nights of the month, the temperature usually drops to around
22.5 °C.

On the warmest days of the month, the temperature usually reaches around
33.5 °C.

Precipitation amounts to
315 mm, distributed over 20 days.
The day lasts on average 12 hours and 0 minutes.

There are on average 5 hours of sunshine per day. So, the sun shines 44% of the time.
The average humidity is 82%. Hence, the air is normally humid.
The average wind speed is of
9.4 kph.

The average sea temperature is of
28.6 °C. Therefore, the sea is pleasantly warm and allows long swims.
June is generally a very hot, muggy month. The average temperature is of
28 °C, with a minimum of
24.4 °C and a maximum of
31.6 °C.

On the coldest nights of the month, the temperature usually drops to around
22.5 °C.

On the warmest days of the month, the temperature usually reaches around
33 °C.

Precipitation amounts to
175 mm, distributed over 13 days.
The day lasts on average 12 hours and 0 minutes.

There are on average 7 hours of sunshine per day. So, the sun shines 59% of the time.
The average humidity is 80%. Hence, the air is normally humid.
The average wind speed is of
10.3 kph.

The average sea temperature is of
28.4 °C. Therefore, the sea is pleasantly warm and allows long swims.
July is generally a very hot, muggy month. The average temperature is of
28 °C, with a minimum of
24.4 °C and a maximum of
31.6 °C.

On the coldest nights of the month, the temperature usually drops to around
22.5 °C.

On the warmest days of the month, the temperature usually reaches around
33 °C.

Precipitation amounts to
130 mm, distributed over 10 days.
The day lasts on average 12 hours and 0 minutes.

There are on average 7.5 hours of sunshine per day. So, the sun shines 64% of the time.
The average humidity is 78%. Hence, the air is normally humid.
The average wind speed is of
11.4 kph.

The average sea temperature is of
27.9 °C. Therefore, the sea is pleasantly warm and allows long swims.
August is generally a very hot, muggy month. The average temperature is of
28.4 °C, with a minimum of
24.8 °C and a maximum of
32.1 °C.

On the coldest nights of the month, the temperature usually drops to around
23 °C.

On the warmest days of the month, the temperature usually reaches around
34 °C.

Precipitation amounts to
30 mm, distributed over 4 days.
The day lasts on average 12 hours and 0 minutes.

There are on average 8.5 hours of sunshine per day. So, the sun shines 70% of the time.
The average humidity is 75%. Hence, the air is normally humid.
The average wind speed is of
14.9 kph.

The average sea temperature is of
27.5 °C. Therefore, the sea is pleasantly warm and allows long swims.
September is generally a very hot, muggy month. The average temperature is of
28.8 °C, with a minimum of
25.2 °C and a maximum of
32.4 °C.

On the coldest nights of the month, the temperature usually drops to around
23 °C.

On the warmest days of the month, the temperature usually reaches around
34 °C.

Precipitation amounts to
25 mm, distributed over 2 days.
The day lasts on average 12 hours and 5 minutes.

There are on average 8.5 hours of sunshine per day. So, the sun shines 69% of the time.
The average humidity is 72%. Hence, the air is normally humid.
The average wind speed is of
18.3 kph.

The average sea temperature is of
27.2 °C. Therefore, the sea is pleasantly warm and allows long swims.
October is generally a very hot, muggy month. The average temperature is of
29 °C, with a minimum of
25.6 °C and a maximum of
32.5 °C.

On the coldest nights of the month, the temperature usually drops to around
23.5 °C.

On the warmest days of the month, the temperature usually reaches around
34 °C.

Precipitation amounts to only
7.6 mm, and all occurs in one day.
The day lasts on average 12 hours and 10 minutes.

There are on average 8 hours of sunshine per day. So, the sun shines 67% of the time.
The average humidity is 71%. Hence, the air is normally humid.
The average wind speed is of
19.8 kph.

The average sea temperature is of
27.3 °C. Therefore, the sea is pleasantly warm and allows long swims.
November, the hottest month of the year, is generally a very hot, muggy month. The average temperature is of
29.1 °C, with a minimum of
25.8 °C and a maximum of
32.5 °C.

On the coldest nights of the month, the temperature usually drops to around
23.5 °C.

On the warmest days of the month, the temperature usually reaches around
34 °C.

Precipitation amounts to
10.5 mm, and all occurs in one day.
The day lasts on average 12 hours and 10 minutes.

There are on average 8 hours of sunshine per day. So, the sun shines 67% of the time.
The average humidity is 71%. Hence, the air is normally humid.
The average wind speed is of
19.2 kph.

The average sea temperature is of
27.5 °C. Therefore, the sea is pleasantly warm and allows long swims.
December, the hottest month of the year, is generally a very hot, muggy month. The average temperature is of
29 °C, with a minimum of
25.7 °C and a maximum of
32.4 °C.

On the coldest nights of the month, the temperature usually drops to around
23 °C.

On the warmest days of the month, the temperature usually reaches around
34 °C.

Precipitation amounts to
75 mm, distributed over 4 days.
The day lasts on average 12 hours and 20 minutes.

There are on average 6.5 hours of sunshine per day. So, the sun shines 54% of the time.
The average humidity is 73%. Hence, the air is normally humid.
The average wind speed is of
18.2 kph.

The average sea temperature is of
27.8 °C. Therefore, the sea is pleasantly warm and allows long swims.