Climate - Colombo (Sri Lanka)

---

---

Colombo's climate is tropical, hot all year round, with a relatively dry season in January and February and two very rainy periods, from April to June and from September to mid-December.
The city is the legislative capital of Sri Lanka and is located in the southwest of the island, at nearly 7 degrees north latitude. Nearby is the city of Sri Jayawardenepura Kotte, the administrative capital.
We are in the rainiest part of the coast, the one that receives abundant rains even in the period that runs from April to June.
Temperatures are quite stable, however, during the day they are a bit higher from January to April. During this period, the temperature gradually increases, and with it showers and thunderstorms, which become frequent in April.
From mid-May to September is the period of the southwest monsoon, which brings abundant rains especially in the first part (mid-May-mid-June) and in the last one (September). In fact, in July and August, the monsoon moves north and mainly affects India, while in Sri Lanka the rains are not very frequent, however, in Colombo and on the south-west coast they still exceed 100 mm (40 in) per month.
From October to mid-December, the rains are frequent and abundant because tropical depressions often form in Sri Lanka.
From mid-December to February, the north-east monsoon period, is the coolest of the year, especially in the first part, it is also a dry period because we are on the western side, protected by the mountains.
Sri Lanka is in the path of tropical cyclones. Typically, on the Indian Ocean north of the Equator, cyclones occur from April to December, although Sri Lanka is usually only affected in November and December, and more rarely in May. However, since the sea is warm all year round, in theory they can also form from January to March, perhaps in a light form (such as tropical storms).

Colombo - Climate data

The average temperature of the coldest month (January) is of 27.5 °C (81.4 °F), that of the warmest month (May) is of 29.5 °C (85.1 °F). Here are the average temperatures.
Precipitation amounts to 2525 millimeters (99.4 inches) per year: it is therefore very abundant. It ranges from 60 mm (2.4 in) in the driest month (January) to 415 mm (16.3 in) in the wettest one (November). Here is the average precipitation.
The sea temperature ranges from 27 °C (81 °F) in August to 29.5 °C (85 °F) in April. Here are the average sea temperatures.
On average, there are around 2620 sunshine hours per year. Here are the average sunshine hours per day.

Colombo - Weather by month

Based on the period 1991-2020

---

In January, the coldest month of the year, the weather in Colombo is usually warm to hot. The average temperature is of 27.5 °C (81 °F), with a minimum of 23.2 °C (73.8 °F) and a maximum of 31.7 °C (89 °F).
On the coldest nights of the month, the temperature usually drops to around 20 °C (68.5 °F).
On the warmest days of the month, the temperature usually reaches around 34 °C (93 °F).
Precipitation amounts to 60 mm (2.4 in), distributed over 5 days.
The day lasts on average 11 hours and 50 minutes.
There are on average 8 sunshine hours per day. So, the sun shines 68% of the time.
The average humidity is 73%. Hence, the air is normally humid.
The average wind speed is 9 kph (6 mph).
The average sea temperature is of 27.5 °C (81.5 °F). Therefore, the sea is pleasantly warm and allows long swims.

---

In February, the weather in Colombo is usually very hot. The average temperature is of 28.0 °C (82 °F), with a minimum of 23.9 °C (75 °F) and a maximum of 32.2 °C (89.9 °F).
On the coldest nights of the month, the temperature usually drops to around 21.5 °C (70.5 °F).
On the warmest days of the month, the temperature usually reaches around 34.5 °C (94 °F).
Precipitation amounts to 75 mm (3 in), distributed over 5 days.
The day lasts on average 11 hours and 55 minutes.
There are on average 8.5 sunshine hours per day. So, the sun shines 73% of the time.
The average humidity is 73%. Hence, the air is normally humid.
The average wind speed is 8 kph (5 mph).
The average sea temperature is of 28 °C (82.5 °F). Therefore, the sea is pleasantly warm and allows long swims.

---

In March, the weather in Colombo is usually very hot. The average temperature is of 28.9 °C (84 °F), with a minimum of 24.9 °C (76.8 °F) and a maximum of 32.8 °C (91.1 °F).
On the coldest nights of the month, the temperature usually drops to around 22 °C (71.5 °F).
On the warmest days of the month, the temperature usually reaches around 34.5 °C (93.5 °F).
Precipitation amounts to 130 mm (5.1 in), distributed over 9 days.
The day lasts on average 12 hours and 5 minutes.
There are on average 9 sunshine hours per day. So, the sun shines 74% 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 29 °C (84 °F). Therefore, the sea is pleasantly warm and allows long swims.

---

In April, the weather in Colombo is usually very hot. The average temperature is of 29.3 °C (85 °F), with a minimum of 25.3 °C (77.5 °F) and a maximum of 33.3 °C (91.9 °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 245 mm (9.6 in), distributed over 14 days.
The day lasts on average 12 hours and 20 minutes.
There are on average 8 sunshine hours per day. So, the sun shines 63% of the time.
The average humidity is 79%. Hence, the air is normally humid.
The average wind speed is 7 kph (4 mph).
The average sea temperature is of 29.5 °C (85.5 °F). Therefore, the sea is pleasantly warm and allows long swims.

---

In May, the warmest month of the year, the weather in Colombo is usually very hot. The average temperature is of 29.5 °C (85 °F), with a minimum of 26.4 °C (79.5 °F) and a maximum of 32.6 °C (90.7 °F).
On the coldest nights of the month, the temperature usually drops to around 24 °C (75 °F).
On the warmest days of the month, the temperature usually reaches around 34 °C (93.5 °F).
Precipitation amounts to 390 mm (15.4 in), distributed over 16 days.
The day lasts on average 12 hours and 25 minutes.
There are on average 6.5 sunshine hours per day. So, the sun shines 52% of the time.
The average humidity is 81%. Hence, the air is normally humid.
The average wind speed is 10 kph (6 mph).
The average sea temperature is of 29 °C (84.5 °F). Therefore, the sea is pleasantly warm and allows long swims.

---

In June, the weather in Colombo is usually very hot. The average temperature is of 29.2 °C (84 °F), with a minimum of 26.4 °C (79.5 °F) and a maximum of 31.9 °C (89.5 °F).
On the coldest nights of the month, the temperature usually drops to around 23.5 °C (74.5 °F).
On the warmest days of the month, the temperature usually reaches around 33.5 °C (92.5 °F).
Precipitation amounts to 185 mm (7.3 in), distributed over 16 days.
The day lasts on average 12 hours and 30 minutes.
There are on average 6.5 sunshine hours per day. So, the sun shines 52% of the time.
The average humidity is 81%. Hence, the air is normally humid.
The average wind speed is 12 kph (7 mph).
The average sea temperature is of 28 °C (82.5 °F). Therefore, the sea is pleasantly warm and allows long swims.

---

In July, the weather in Colombo is usually very hot. The average temperature is of 28.9 °C (84 °F), with a minimum of 26.3 °C (79.3 °F) and a maximum of 31.5 °C (88.7 °F).
On the coldest nights of the month, the temperature usually drops to around 23 °C (73.5 °F).
On the warmest days of the month, the temperature usually reaches around 33.5 °C (92 °F).
Precipitation amounts to 120 mm (4.7 in), distributed over 12 days.
The day lasts on average 12 hours and 30 minutes.
There are on average 6.5 sunshine hours per day. So, the sun shines 52% of the time.
The average humidity is 80%. Hence, the air is normally humid.
The average wind speed is 11 kph (7 mph).
The average sea temperature is of 27.5 °C (81 °F). Therefore, the sea is pleasantly warm and allows long swims.

---

In August, the weather in Colombo is usually very hot. The average temperature is of 28.7 °C (84 °F), with a minimum of 26.1 °C (79 °F) and a maximum of 31.3 °C (88.3 °F).
On the coldest nights of the month, the temperature usually drops to around 23 °C (73 °F).
On the warmest days of the month, the temperature usually reaches around 33 °C (91.5 °F).
Precipitation amounts to 120 mm (4.7 in), distributed over 11 days.
The day lasts on average 12 hours and 20 minutes.
There are on average 6.5 sunshine hours per day. So, the sun shines 53% of the time.
The average humidity is 78%. Hence, the air is normally humid.
The average wind speed is 11 kph (7 mph).
The average sea temperature is of 27 °C (81 °F). Therefore, the sea is pleasantly warm and allows long swims.

---

In September, the weather in Colombo is usually very hot. The average temperature is of 28.3 °C (83 °F), with a minimum of 25.5 °C (77.9 °F) and a maximum of 31.2 °C (88.2 °F).
On the coldest nights of the month, the temperature usually drops to around 23 °C (73.5 °F).
On the warmest days of the month, the temperature usually reaches around 33 °C (91.5 °F).
Precipitation amounts to 245 mm (9.6 in), distributed over 15 days.
The day lasts on average 12 hours and 5 minutes.
There are on average 6.5 sunshine hours per day. So, the sun shines 52% of the time.
The average humidity is 79%. Hence, the air is normally humid.
The average wind speed is 10 kph (6 mph).
The average sea temperature is of 27.5 °C (81.5 °F). Therefore, the sea is pleasantly warm and allows long swims.

---

In October, the weather in Colombo is usually very hot. The average temperature is of 28.1 °C (83 °F), with a minimum of 24.8 °C (76.7 °F) and a maximum of 31.4 °C (88.6 °F).
On the coldest nights of the month, the temperature usually drops to around 23 °C (74 °F).
On the warmest days of the month, the temperature usually reaches around 32.5 °C (91 °F).
Precipitation amounts to 365 mm (14.4 in), distributed over 17 days.
The day lasts on average 12 hours and 0 minutes.
There are on average 6.5 sunshine hours per day. So, the sun shines 54% of the time.
The average humidity is 81%. Hence, the air is normally humid.
The average wind speed is 8 kph (5 mph).
The average sea temperature is of 28 °C (82.5 °F). Therefore, the sea is pleasantly warm and allows long swims.

---

In November, the weather in Colombo is usually very hot. The average temperature is of 27.7 °C (82 °F), with a minimum of 24 °C (75.3 °F) and a maximum of 31.4 °C (88.5 °F).
On the coldest nights of the month, the temperature usually drops to around 21.5 °C (70.5 °F).
On the warmest days of the month, the temperature usually reaches around 33.5 °C (92 °F).
Precipitation amounts to 415 mm (16.3 in), distributed over 15 days.
The day lasts on average 11 hours and 50 minutes.
There are on average 7 sunshine hours per day. So, the sun shines 59% 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 28.5 °C (83.5 °F). Therefore, the sea is pleasantly warm and allows long swims.

---

In December, the weather in Colombo is usually warm to hot. The average temperature is of 27.5 °C (81 °F), with a minimum of 23.8 °C (74.8 °F) and a maximum of 31.2 °C (88.1 °F).
On the coldest nights of the month, the temperature usually drops to around 22 °C (71.5 °F).
On the warmest days of the month, the temperature usually reaches around 33.5 °C (92.5 °F).
Precipitation amounts to 175 mm (6.9 in), distributed over 10 days.
The day lasts on average 11 hours and 40 minutes.
There are on average 7 sunshine hours per day. So, the sun shines 60% of the time.
The average humidity is 78%. Hence, the air is normally humid.
The average wind speed is 8 kph (5 mph).
The average sea temperature is of 28 °C (82.5 °F). Therefore, the sea is pleasantly warm and allows long swims.