, with very mild or pleasantly warm winters and hot, humid and rainy summers. The rains are abundant from May to October.
The city is the capital of the province of Hainan and is located in the far south of China, at 20 degrees north latitude, on the north coast of the island of
, from December to February, is very mild, however, the north-east monsoon brings cloudy days, during which there are some drizzles, or fog can form. Sometimes, cold and windy days can occur, with highs around 13 °C (55 °F) or even below. In January 2016, the temperature dropped to 6 °C (43 °F), with a maximum of 8 °C (46.5 °F).
, the tropical cyclones of Southeast Asia. Typically, typhoons occur in this area from June to mid-November, but sometimes (though very rarely) they have affected this area outside of this period, i.e. in April or in May.
It is difficult to find the best time to visit Haikou, however you can choose the cooler period, from mid-November to the end of March. It must be said that we are on the north side of the island of Hainan, where there is not much sun in this period, and the sea is also cooler than on the southern side.
. Here are the average temperatures.
January, the coldest month of the year, is generally a warm month. The average temperature is of
18.4 °C, with a minimum of
15.6 °C and a maximum of
21.2 °C.

On the coldest nights of the month, the temperature usually drops to around
10 °C. However, it dropped to
5.9 °C in January 2016.

On the warmest days of the month, the temperature usually reaches around
28 °C. However, it reached
32.1 °C in January 2006.

Precipitation amounts to
20 mm, distributed over 9 days.
The day lasts on average 11 hours and 5 minutes.

There are on average 3.5 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
10 kph.

The average sea temperature is of
21 °C. Therefore, the sea is cool for swimming.
February is generally a warm month. The average temperature is of
19.8 °C, with a minimum of
16.8 °C and a maximum of
22.7 °C.

On the coldest nights of the month, the temperature usually drops to around
11 °C. However, it dropped to
7 °C in February 2018.

On the warmest days of the month, the temperature usually reaches around
31 °C. However, it reached
36.6 °C in February 1994.

Precipitation amounts to
35 mm, distributed over 11 days.
The day lasts on average 11 hours and 30 minutes.

There are on average 3.5 hours of sunshine per day. So, the sun shines 30% of the time.
The average humidity is 85%. Hence, the air is normally humid.
The average wind speed is of
10.1 kph.

The average sea temperature is of
21 °C. Therefore, the sea is cool for swimming.
March is generally a warm to hot, muggy month. The average temperature is of
23 °C, with a minimum of
19.6 °C and a maximum of
26.4 °C.

On the coldest nights of the month, the temperature usually drops to around
14 °C. However, it dropped to
9.9 °C in March 2005.

On the warmest days of the month, the temperature usually reaches around
34.5 °C. However, it reached
38.1 °C in March 1999.

Precipitation amounts to
50 mm, distributed over 10 days.
The day lasts on average 12 hours and 5 minutes.

There are on average 4.5 hours of sunshine per day. So, the sun shines 37% of the time.
The average humidity is 82%. Hence, the air is normally humid.
The average wind speed is of
10.9 kph.

The average sea temperature is of
22 °C. Therefore, the sea is cool for swimming.
April is generally a warm to hot, muggy month. The average temperature is of
26.3 °C, with a minimum of
22.8 °C and a maximum of
29.9 °C.

On the coldest nights of the month, the temperature usually drops to around
18 °C. However, it dropped to
14.5 °C in April 1996.

On the warmest days of the month, the temperature usually reaches around
36.5 °C. However, it reached
39.6 °C in April 2001.

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

There are on average 5.5 hours of sunshine per day. So, the sun shines 44% of the time.
The average humidity is 80%. Hence, the air is normally humid.
The average wind speed is of
10.6 kph.

The average sea temperature is of
24 °C. Therefore, the sea is warm enough for swimming.
May is generally a very hot, muggy month. The average temperature is of
28.5 °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
21.5 °C. However, it dropped to
20 °C in May 2008.

On the warmest days of the month, the temperature usually reaches around
36.5 °C. However, it reached
38.8 °C in May 2005.

Precipitation amounts to
185 mm, distributed over 16 days.
The day lasts on average 13 hours and 5 minutes.

There are on average 7 hours of sunshine per day. So, the sun shines 54% of the time.
The average humidity is 80%. Hence, the air is normally humid.
The average wind speed is of
9.2 kph.

The average sea temperature is of
27 °C. Therefore, the sea is pleasantly warm and allows long swims.
June, the hottest month of the year, is generally a very hot, muggy month. The average temperature is of
29.5 °C, with a minimum of
25.7 °C and a maximum of
33.3 °C.

On the coldest nights of the month, the temperature usually drops to around
23.5 °C. However, it dropped to
20.2 °C in June 2002.

On the warmest days of the month, the temperature usually reaches around
36.5 °C. However, it reached
37.7 °C in June 2003.

Precipitation amounts to
210 mm, distributed over 16 days.
The day lasts on average 13 hours and 20 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 56% of the time.
The average humidity is 79%. Hence, the air is normally humid.
The average wind speed is of
8.8 kph.

The average sea temperature is of
29 °C. Therefore, the sea is pleasantly warm and allows long swims.
July is generally a very hot, muggy month. The average temperature is of
29.4 °C, with a minimum of
25.8 °C and a maximum of
33.1 °C.

On the coldest nights of the month, the temperature usually drops to around
23.5 °C. However, it dropped to
22 °C in July 2004.

On the warmest days of the month, the temperature usually reaches around
36 °C. However, it reached
37.7 °C in July 1998.

Precipitation amounts to
210 mm, distributed over 14 days.
The day lasts on average 13 hours and 10 minutes.

There are on average 8 hours of sunshine per day. So, the sun shines 62% of the time.
The average humidity is 79%. Hence, the air is normally humid.
The average wind speed is of
9.1 kph.

The average sea temperature is of
29 °C. Therefore, the sea is pleasantly warm and allows long swims.
August is generally a very hot, muggy month. The average temperature is of
28.9 °C, with a minimum of
25.6 °C and a maximum of
32.3 °C.

On the coldest nights of the month, the temperature usually drops to around
23.5 °C. However, it dropped to
22.3 °C in August 2014.

On the warmest days of the month, the temperature usually reaches around
35 °C. However, it reached
37 °C in August 1994.

Precipitation amounts to
225 mm, distributed over 15 days.
The day lasts on average 12 hours and 50 minutes.

There are on average 7 hours of sunshine per day. So, the sun shines 55% of the time.
The average humidity is 81%. Hence, the air is normally humid.
The average wind speed is of
8.1 kph.

The average sea temperature is of
29 °C. Therefore, the sea is pleasantly warm and allows long swims.
September is generally a very hot, muggy month. The average temperature is of
27.9 °C, with a minimum of
24.9 °C and a maximum of
30.8 °C.

On the coldest nights of the month, the temperature usually drops to around
23 °C. However, it dropped to
19.7 °C in September 1997.

On the warmest days of the month, the temperature usually reaches around
33.5 °C. However, it reached
35.7 °C in September 2006.

Precipitation amounts to
250 mm, distributed over 15 days.
The day lasts on average 12 hours and 10 minutes.

There are on average 6.5 hours of sunshine per day. So, the sun shines 53% of the time.
The average humidity is 81%. Hence, the air is normally humid.
The average wind speed is of
8.6 kph.

The average sea temperature is of
29 °C. Therefore, the sea is pleasantly warm and allows long swims.
October is generally a warm to hot, muggy month. The average temperature is of
26.1 °C, with a minimum of
23.4 °C and a maximum of
28.8 °C.

On the coldest nights of the month, the temperature usually drops to around
20 °C. However, it dropped to
15.5 °C in October 1991.

On the warmest days of the month, the temperature usually reaches around
32 °C. However, it reached
34.5 °C in October 2003.

Precipitation amounts to
200 mm, distributed over 13 days.
The day lasts on average 11 hours and 40 minutes.

There are on average 5.5 hours of sunshine per day. So, the sun shines 49% of the time.
The average humidity is 78%. Hence, the air is normally humid.
The average wind speed is of
10.3 kph.

The average sea temperature is of
28 °C. Therefore, the sea is pleasantly warm and allows long swims.
November is generally a warm to hot, muggy month. The average temperature is of
23.2 °C, with a minimum of
20.6 °C and a maximum of
25.8 °C.

On the coldest nights of the month, the temperature usually drops to around
16 °C. However, it dropped to
11.4 °C in November 2009.

On the warmest days of the month, the temperature usually reaches around
30 °C. However, it reached
34.7 °C in November 1997.

Precipitation amounts to
95 mm, distributed over 10 days.
The day lasts on average 11 hours and 10 minutes.

There are on average 5 hours of sunshine per day. So, the sun shines 43% of the time.
The average humidity is 78%. Hence, the air is normally humid.
The average wind speed is of
10.4 kph.

The average sea temperature is of
25 °C. Therefore, the sea is warm enough for swimming.
December is generally a warm month. The average temperature is of
19.8 °C, with a minimum of
17.3 °C and a maximum of
22.2 °C.

On the coldest nights of the month, the temperature usually drops to around
11.5 °C. However, it dropped to
7.4 °C in December 1991.

On the warmest days of the month, the temperature usually reaches around
27.5 °C. However, it reached
31.2 °C in December 2012.

Precipitation amounts to
35 mm, distributed over 8 days.
The day lasts on average 10 hours and 55 minutes. December 21, the winter solstice, is the shortest day of the year in the Northern Hemisphere.

There are on average 4 hours of sunshine per day. So, the sun shines 39% of the time.
The average humidity is 79%. Hence, the air is normally humid.
The average wind speed is of
10.4 kph.

The average sea temperature is of
23 °C. Therefore, the sea can be considered barely acceptable for swimming.