, with a long, dry season from November to May, and a rainy season from June to October.
The city (also known as Ndar) is located in the northwest of Senegal, on the coast, and at the mouth of the Senegal River, beyond which lies Mauritania.
The old city is located on an island, in front of which there is a barrier island, called Langue de Barbarie.
To the northeast is the Djoudj National Bird Sanctuary. To the south-west is the Lompoul desert.
The length of the rainy period and the amount of rainfall varies according to the years, however, the region of Saint-Louis, where precipitation drops below 400 mm (15.5 in) per year, is the driest in the country.
During the day it is hot all year round, but from December to February the nights are quite cool and the humidity is quite low.
In St. Louis, the
. Here are the average temperatures.
January, the coolest month of the year, is generally a warm to hot month. However, there are remarkable differences between night and day. The average temperature is of
23.8 °C, with a minimum of
16.1 °C and a maximum of
31.4 °C.

On the coldest nights of the month, the temperature usually drops to around
13 °C.

On the warmest days of the month, the temperature usually reaches around
37 °C.

Precipitation amounts to only
2.5 mm, distributed over 0 days.
The day lasts on average 11 hours and 20 minutes.

There are on average 8 hours of sunshine per day. So, the sun shines 69% of the time.
The average humidity is 45%.
The average wind speed is of
12.6 kph.

The average sea temperature is of
20.5 °C. Therefore, the sea is cool for swimming.
February is generally a warm to hot month. However, there are remarkable differences between night and day. The average temperature is of
24.8 °C, with a minimum of
17.1 °C and a maximum of
32.4 °C.

On the coldest nights of the month, the temperature usually drops to around
14 °C.

On the warmest days of the month, the temperature usually reaches around
38.5 °C.

Precipitation amounts to only
0.6 mm, distributed over 0 days.
The day lasts on average 11 hours and 35 minutes.

There are on average 8.5 hours of sunshine per day. So, the sun shines 73% of the time.
The average humidity is 49%.
The average wind speed is of
14.2 kph.

The average sea temperature is of
19.5 °C. Therefore, the sea is very cool for swimming.
March is generally a warm to hot month. However, there are remarkable differences between night and day. The average temperature is of
25.4 °C, with a minimum of
17.8 °C and a maximum of
33 °C.

On the coldest nights of the month, the temperature usually drops to around
15 °C.

On the warmest days of the month, the temperature usually reaches around
40.5 °C.

Precipitation amounts to only
0.2 mm, distributed over 0 days.
The day lasts on average 12 hours and 5 minutes.

There are on average 9 hours of sunshine per day. So, the sun shines 74% of the time.
The average humidity is 57%.
The average wind speed is of
15.9 kph.

The average sea temperature is of
19.5 °C. Therefore, the sea is very cool for swimming.
April is generally a warm to hot month. However, there are remarkable differences between night and day. The average temperature is of
24.9 °C, with a minimum of
18.3 °C and a maximum of
31.5 °C.

On the coldest nights of the month, the temperature usually drops to around
15.5 °C.

On the warmest days of the month, the temperature usually reaches around
42 °C.

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

There are on average 9.5 hours of sunshine per day. So, the sun shines 76% of the time.
The average humidity is 66%.
The average wind speed is of
17.4 kph.

The average sea temperature is of
19.8 °C. Therefore, the sea is very cool for swimming.
May is generally a warm to hot, muggy month. The average temperature is of
25 °C, with a minimum of
19.7 °C and a maximum of
30.3 °C.

On the coldest nights of the month, the temperature usually drops to around
17 °C.

On the warmest days of the month, the temperature usually reaches around
40 °C.

Precipitation amounts to only
0.1 mm, distributed over 0 days.
The day lasts on average 12 hours and 55 minutes.

There are on average 9 hours of sunshine per day. So, the sun shines 70% of the time.
The average humidity is 73%. Hence, the air is normally humid.
The average wind speed is of
16.5 kph.

The average sea temperature is of
20.9 °C. Therefore, the sea is cool for swimming.
June is generally a warm to hot, muggy month. The average temperature is of
26.6 °C, with a minimum of
22.7 °C and a maximum of
30.6 °C.

On the coldest nights of the month, the temperature usually drops to around
20 °C.

On the warmest days of the month, the temperature usually reaches around
39 °C.

Precipitation amounts to only
6.5 mm, distributed over 0 days.
The day lasts on average 13 hours and 5 minutes. June 21, the summer solstice, is the longest day of the year in the Northern Hemisphere.

There are on average 7.5 hours of sunshine per day. So, the sun shines 57% of the time.
The average humidity is 79%. Hence, the air is normally humid.
The average wind speed is of
14.5 kph.

The average sea temperature is of
23.8 °C. Therefore, the sea is warm enough for swimming.
July is generally a very hot, muggy month. The average temperature is of
27.9 °C, with a minimum of
24.5 °C and a maximum of
31.3 °C.

On the coldest nights of the month, the temperature usually drops to around
21 °C.

On the warmest days of the month, the temperature usually reaches around
37 °C.

Precipitation amounts to
43.1 mm, distributed over 3 days.
The day lasts on average 13 hours and 0 minutes.

There are on average 8 hours of sunshine per day. So, the sun shines 61% of the time.
The average humidity is 79%. Hence, the air is normally humid.
The average wind speed is of
13.7 kph.

The average sea temperature is of
26.5 °C. Therefore, the sea is pleasantly warm and allows long swims.
August is generally a very hot, muggy month. The average temperature is of
28.6 °C, with a minimum of
25.1 °C and a maximum of
32.1 °C.

On the coldest nights of the month, the temperature usually drops to around
21 °C.

On the warmest days of the month, the temperature usually reaches around
36.5 °C.

Precipitation amounts to
91.5 mm, distributed over 7 days.
The day lasts on average 12 hours and 35 minutes.

There are on average 8 hours of sunshine per day. So, the sun shines 64% of the time.
The average humidity is 81%. Hence, the air is normally humid.
The average wind speed is of
12.3 kph.

The average sea temperature is of
27.8 °C. Therefore, the sea is pleasantly warm and allows long swims.
September is generally a very hot, muggy month. The average temperature is of
29 °C, with a minimum of
25.1 °C and a maximum of
33 °C.

On the coldest nights of the month, the temperature usually drops to around
20.5 °C.

On the warmest days of the month, the temperature usually reaches around
38.5 °C.

Precipitation amounts to
103.7 mm, distributed over 7 days.
The day lasts on average 12 hours and 10 minutes.

There are on average 7.5 hours of sunshine per day. So, the sun shines 62% of the time.
The average humidity is 81%. Hence, the air is normally humid.
The average wind speed is of
10.8 kph.

The average sea temperature is of
28.4 °C. Therefore, the sea is pleasantly warm and allows long swims.
October, the hottest month of the year, is generally a very hot, muggy month. The average temperature is of
29.2 °C, with a minimum of
24 °C and a maximum of
34.5 °C.

On the coldest nights of the month, the temperature usually drops to around
20 °C.

On the warmest days of the month, the temperature usually reaches around
41 °C.

Precipitation amounts to
23.7 mm, distributed over 2 days.
The day lasts on average 11 hours and 50 minutes.

There are on average 8.5 hours of sunshine per day. So, the sun shines 71% of the time.
The average humidity is 72%. Hence, the air is normally humid.
The average wind speed is of
11.6 kph.

The average sea temperature is of
27.9 °C. Therefore, the sea is pleasantly warm and allows long swims.
November is generally a warm to hot month. However, there are remarkable differences between night and day. The average temperature is of
27.5 °C, with a minimum of
20.3 °C and a maximum of
34.7 °C.

On the coldest nights of the month, the temperature usually drops to around
17 °C.

On the warmest days of the month, the temperature usually reaches around
40 °C.

Precipitation amounts to only
0.1 mm, distributed over 0 days.
The day lasts on average 11 hours and 25 minutes.

There are on average 8 hours of sunshine per day. So, the sun shines 72% of the time.
The average humidity is 56%.
The average wind speed is of
11.4 kph.

The average sea temperature is of
25.9 °C. Therefore, the sea is warm enough for swimming.
December is generally a warm to hot month. However, there are remarkable differences between night and day. The average temperature is of
25 °C, with a minimum of
17.4 °C and a maximum of
32.5 °C.

On the coldest nights of the month, the temperature usually drops to around
14 °C.

On the warmest days of the month, the temperature usually reaches around
38 °C.

Precipitation amounts to only
0.3 mm, distributed over 0 days.
The day lasts on average 11 hours and 10 minutes. December 21, the winter solstice, is the shortest day of the year in the Northern Hemisphere.

There are on average 7.5 hours of sunshine per day. So, the sun shines 67% of the time.
The average humidity is 49%.
The average wind speed is of
11.8 kph.

The average sea temperature is of
23.2 °C. Therefore, the sea can be considered barely acceptable for swimming.