Index


Introduction


In Sri Lanka, formerly Ceylon, the climate is tropical, with a hot and humid weather throughout the year. The country is located just north of the equator.
The rainfall pattern is determined by the monsoon regime, but also by the two passages of the sun at the zenith, in April and October. In addition, the inland elevations, which are higher in the south-central part of the island, influence the intensity and the distribution of rainfall in the different areas: the south-western mountain slope and the coastal area where the capital Colombo is found are the rainiest, while the driest areas are the north-west coast (see Mannar, Jaffna) and the south-east coast (see Hambantota).
The highest mountain is Pidurutalagala (or Mount Pedro), 2,524 metres (8,280 feet) high.
The rains in Sri Lanka, as usually happens in countries having a tropical climate, occur mainly in the form of downpour or thunderstorm in the afternoon or in the evening.
There are two peaks in the rainfall: the first, in April and May, only affects the south-west and the interior, while the second, from October to December, due to the retreating monsoon, affects the whole country.
From May to September, the southwest monsoon prevails, but it releases the bulk of the rains in India, and in Sri Lanka it brings heavy rains only in the southwest coast (see Colombo) and in the mountainous interior. However, during this period on the western side the sea is rough, and there may be dangerous currents, except for the beaches partially sheltered by a coral reef (see the beaches of Unawatuna and Hikkaduwa).
From March to May, before the arrival of the monsoon, there is an increase in temperature, more noticeable in the north-central part of the country.
The amount of sunshine is never low on the coasts, because even in the rainy months there are a few hours of sunshine a day, however, it is better in the dry season, when there are 8/9 hours of sunshine per day. On the contrary, in inland mountainous areas, cloudiness is more common, and the sun is rarely seen from May to December.

The north-west



Climate of the northwest

In the north-west (see Mannar, Jaffna), partially protected by neighbouring India, between 1,000 and 1,300 mm (40 to 50 in) of rain per year fall, and the rains are abundant only between October and December. The temperatures are high throughout the year, but compared to the south there's a greater difference between the winter months and the pre-monsoon period, from March to May. The sea is warm all year round (see below).

Jaffna

In Jaffna, located in the north-western tip of the country, the weather is hot all year round. Being the summer monsoon very weak, the heat remains intense even in summer. Here are the average temperatures.
Jaffna - Average temperatures
MonthJanFebMarAprMayJunJulAugSepOctNovDec
Min (°C)232323262727262626252424
Max (°C)283032333333333232312928
Min (°F)737373798181797979777575
Max (°F)828690919191919090888482

In Jaffna, 1,300 mm (51 inches) of rain per year fall, but the rains are really abundant only from October to December. Here is the average rainfall.
Jaffna - Average precipitation
MonthJanFebMarAprMayJunJulAugSepOctNovDecYear
Prec.(mm)7035204545254050752503552951305
Prec.(in)2.81.40.81.81.811.6239.81411.651.4
Days42243233511151367

In the north-west, the sun shines often from January to May, while in the rest of the year all in all the sun is seen for a decent number of hours, both in the summer (where it rains little, but there's still some cloudiness related to the south-west monsoon), and at the end of the year (when the north-east monsoon discharges abundant rains, but otherwise the sun shines). Here are the average sunshine hours in Jaffna.
Jaffna - Sunshine
MonthJanFebMarAprMayJunJulAugSepOctNovDec
Hours899986677767

Mannar

In Mannar, a little further to the south, the climate is similar to that of Jaffna. Here are the average temperatures.
Mannar - Average temperatures
MonthJanFebMarAprMayJunJulAugSepOctNovDec
Min (°C)242424262727272626252524
Max (°C)293032333231313131313029
Min (°F)757575798181817979777775
Max (°F)848690919088888888888684

In Mannar, the rains drop even below 1,000 mm (40 in) per year; however, in addition to the rainy season at the end of the year, there is a certain increase in rainfall in April. Here is the average precipitation.
Mannar - Average precipitation
MonthJanFebMarAprMayJunJulAugSepOctNovDecYear
Prec.(mm)40604580455121240165235220963
Prec.(in)1.62.41.83.11.80.20.50.51.66.59.38.737.9
Days43363111210141260

Further south, in Puttalam and Kalpitiya, the climate is similar, but the increase in rainfall in April and May becomes evident, so much so that in April 175 mm (7 in) of rain fall. Here is the average rainfall at Puttalam.
Puttalam - Average precipitation
MonthJanFebMarAprMayJunJulAugSepOctNovDecYear
Prec.(mm)55406517595401515652402501401195
Prec.(in)2.21.62.66.93.71.60.60.62.69.49.85.547
Days75454245612161686

The south-west coast



Climate of the south-west coast

The south-western coast, from Negombo to Tangalle, is decidedly more rainy than the north-western one, and does not experience a real dry season, even though the rains decrease from January to March, and to a lesser extent from June to August. In this part of the coast there are beaches like Bentota, Hikkaduwa, Unawatuna and Mirissa.

Colombo

The Sri Lankan capital, Colombo, is located in the rainiest part of the country, namely the south-western side. Here, 2,500 mm (99 in) of rain per year fall, with two maxima, in April-May and October-November, when precipitation exceeds 240 mm (9.5 in) per month. Between the two rainy periods, there is a relative summer decrease in July and August, with about 120 mm (4.7 in), while the driest months, with less than 100 mm (4 in) per month, are January and February.
Here is the average precipitation.
Colombo - Average precipitation
MonthJanFebMarAprMayJunJulAugSepOctNovDecYear
Prec.(mm)60751302453901851201202453654151752525
Prec.(in)2.435.19.615.47.34.74.79.614.416.36.999.4
Days559141616121115171510145

In Colombo, the heat is constant throughout the year, with highs around 30/32 °C (86/90 °F), but the humidity is a bit lower in January and February. Here are the average temperatures.
Colombo - Average temperatures
MonthJanFebMarAprMayJunJulAugSepOctNovDec
Min (°C)222324252626252525242323
Max (°C)313132323130303030303030
Min (°F)727375777979777777757373
Max (°F)888890908886868686868686

In Colombo the sun shines regularly from January to April, while from May to September it does not shine very often, being directly exposed to the southwest monsoon.
Colombo - Sunshine
MonthJanFebMarAprMayJunJulAugSepOctNovDec
Hours899866666677

In the extreme south-west, at Galle, it rains even more than in Colombo, and precipitation reaches 2,400 mm (95 in) per year. However, here too the rains drop to an acceptable level from January to March. Here is the average rainfall.
Galle - Average precipitation
MonthJanFebMarAprMayJunJulAugSepOctNovDecYear
Prec.(mm)85701102052901901651852553253201752380
Prec.(in)3.32.84.38.111.47.56.57.31012.812.66.993.7
Days869121617161618181612164

Unawatuna beach

Further east, in Matara and Tangalle, the rains decrease a little, but remain abundant. In Matara, at the southern tip of Sri Lanka, 2,000 mm (78 in) of rain fall per year, and in Tangalle 1,900 mm (75 in).

The east coast



Climate of the east coast

The east coast directly receives the north-east monsoon that occur the end of the year, so it rains a lot from October to December; the monsoon lingers on, though weakened, in January and sometimes in February, in fact in some years the rains are abundant even in February. Instead, this coast is sheltered from the south-west monsoon that blows from May to September, so in this period the sun shines and it is also very hot. Therefore, even though the total rainfall is not low, the landscape is semi-arid.
On average, around 1,600 mm (63 in) of rain per year fall.

Trincomalee

In Trincomalee it is hot all year round, even though in the rainy season the maximum temperatures drops below 30 °C (86 °F), but the humidity increases. On the other hand, the summer period as well as being not very rainy, is also particularly hot, given that the prevailing currents come from the interior.
Trincomalee - Average temperatures
MonthJanFebMarAprMayJunJulAugSepOctNovDec
Min (°C)242425262626262625252424
Max (°C)282931333435343434322928
Min (°F)757577797979797977777575
Max (°F)828488919395939393908482

In Trincomalee the rains are abundant from October to January, and very abundant in November and December, at the height of the retreating monsoon. Here is the average precipitation.
Trincomalee - Average precipitation
MonthJanFebMarAprMayJunJulAugSepOctNovDecYear
Prec.(mm)1701055550502565851002203453641635
Prec.(in)6.74.12.22212.63.33.98.713.614.364.4
Days115454245612161690

On the east coast the sun regularly shines much of the year, therefore even in the summer, since the area is in a rain shadow from to the southwest monsoon.
Trincomalee - Sunshine
MonthJanFebMarAprMayJunJulAugSepOctNovDec
Hours81010988887765

Batticaloa

Further south, in Batticaloa the climate is similar to that of Trincomalee. Here are the average temperatures.
Batticaloa - Average temperatures
MonthJanFebMarAprMayJunJulAugSepOctNovDec
Min (°C)232424252626252525242424
Max (°C)282930323334333332312928
Min (°F)737575777979777777757575
Max (°F)828486909193919190888482

In Batticaloa too, the rains are abundant from October to January, and very abundant in November and December, at the height of the retreating monsoon. Here is the average precipitation.
Batticaloa - Average precipitation
MonthJanFebMarAprMayJunJulAugSepOctNovDecYear
Prec.(mm)210130905540254050651803504201650
Prec.(in)8.35.13.52.21.611.622.67.113.816.565
Days117653234511161790

In Batticaloa too, the sun shines regularly during the summer months.
Batticaloa - Sunshine
MonthJanFebMarAprMayJunJulAugSepOctNovDec
Hours689989888876

Further south, in Kalmunai and Arugam Bay, a famous beach among surfers, the climate is similar.

Southeast coast



Climate of the southeast coast

On the southeastern coast (see Hambantota, Kirinda), which is is quite protected even from the north-east monsoon of the end of the year, the rains are again quite contained, as in the north-west, and amount to 1,000/1,200 mm (40/47 in) per year, with a relative peak in April and May, and a more pronounced one from October to December.

Hambantota

In Hambantota the rainfall amounts to 1,000 mm (40 in) per year, and it exceeds 100 mm (4 in) per month only from October to December. Here is the average rainfall.
Hambantota - Average precipitation
MonthJanFebMarAprMayJunJulAugSepOctNovDecYear
Prec.(mm)6045659590605055701501901201045
Prec.(in)2.41.82.63.73.52.422.22.85.97.54.741.1
Days5358876571012985

Sea temperature


As mentioned, in Sri Lanka the sea is warm all year round, as we can see from the water temperature at Colombo.
Colombo - Sea temperature
MonthJanFebMarAprMayJunJulAugSepOctNovDec
Temp (°C)282829302928272727282828
Temp (°F)828284868482818181828282

The interior



Climate of the inland areas

In the interior, at low altitude the heat is particularly intense.

Anuradhapura

In Anuradhapura, in the north-central inland region, the heat is intense throughout the year, but especially between March and September.
Anuradhapura - Average temperatures
MonthJanFebMarAprMayJunJulAugSepOctNovDec
Min (°C)212123242525252424232322
Max (°C)303234343333333333323029
Min (°F)707073757777777575737372
Max (°F)869093939191919191908684

In Anuradhapura the rainfall amounts to 1,300 mm (51 in) per year, with a peak between October and December, and a minimum in summer, between June and August. In April and May there is an increase in the afternoon showers, but not so intense as in the south-west.

Anuradhapura

With increasing altitude, the climate becomes milder, but also rainier.

Kandy

Already in Kandy, at 450 metres (1,450 ft) above sea level and in the centre of the island, the heat is slightly less intense than in the plains: the daily average ranges from 23.5 °C (74 °F) in January, to 26 °C (79 °F) in April.
Kandy - Average temperatures
MonthJanFebMarAprMayJunJulAugSepOctNovDec
Min (°C)181920212221212120202020
Max (°C)283031313028282828292828
Min (°F)646668707270707068686868
Max (°F)828688888682828282848282

Rainfall in Kandy amounts to 1,850 mm (72 in) per year, with a minimum from January in March, and a maximum between October and December. In summer, although the rainfall exceeds 100 mm (4 in) per month, all in all it does not rain very much, so much so that the Buddhist festival Esala Perahera is held for 10 nights in a row in July or August. Here is the average precipitation.
Kandy - Average precipitation
MonthJanFebMarAprMayJunJulAugSepOctNovDecYear
Prec.(mm)8075701901451301301151552652951951840
Prec.(in)3.132.87.55.75.15.14.56.110.411.67.772.4
Days658141115141313171614146

Nuwara Eliya

In Nuwara Eliya, at 1,900 metres (6,200 ft) above sea level, the temperature is spring-like all year round, but at night it can be a bit cold between December and March. Here are the average temperatures.
Nuwara Eliya - Average temperatures
MonthJanFebMarAprMayJunJulAugSepOctNovDec
Min (°C)91010111313131312121211
Max (°C)202123232119191919202019
Min (°F)485050525555555554545452
Max (°F)687073737066666666686866

In Nuwara Eliya, 1,900 mm (75 in) of rain per year fall; the rainfall pattern is similar to that of Kandy; here too there is no real dry season, although in January, February and March, the rains are not very abundant and are around 70/100 mm (2.8/4 in) per month.
Nuwara Eliya - Average precipitation
MonthJanFebMarAprMayJunJulAugSepOctNovDecYear
Prec.(mm)10080701601751701651601802252201951905
Prec.(in)3.93.12.86.36.96.76.56.37.18.98.77.775
Days878131316171615181715163

In Nuwara Eliya the sun is rarely seen from May to September, and in any case it does not shine too often even in the least rainy months, February and March.
Nuwara Eliya - Sunshine
MonthJanFebMarAprMayJunJulAugSepOctNovDec
Hours566533223445

Tropical cyclones



Sri Lanka lies in the path of tropical cyclones, even though most of them pass to the north, over India and the Bay of Bengal. The period of cyclones, which are able to bring heavy rains and strong winds, goes from April to December, with two peaks in May and November.
However, to tell the truth some tropical depressions can form even in winter, since at so low a latitude, as we have seen, the sea remains warm all year round, so it's always able to provide energy for their formation.

When to go



Notwithstanding the fact that it is an equatorial country, in which the rains can have an irregular trend from one year to the next, the best months to visit Sri Lanka as a whole, therefore also the cities of the interior, are February and March. In fact, in January it still rains a lot on the east coast, from April to September it rains a lot in the south-west and in inland areas, and then from October to December it rains a lot in the whole country.
For a beach holiday, on the other hand, in the northwest you can go from mid-January to mid-September, in Puttalam and Kalpitiya and in the south-west coast (from Colombo to Tangalle) from January to March, in the east coast (Trincomalee, Batticaloa, Kalmunai) from February (or for safety from March) to mid-September, in the south-east coast (Hambantota) from January to mid-September.
However, may can be avoided for the highest risk of tropical cyclones, and because the arrival of the monsoon, around the 20th of the month, can cause abundant rains throughout the country, which can trigger floods, as happened in May 2016, 2017 and 2018.
In summer, from June to August, the east coast is preferable, because it is the sunniest and the sea is calm. Instead in this period the south-west coast, from Colombo to Tangalle, besides being rainy, has also the rough sea.

What to pack



All year round, light clothes, of natural fibres, light raincoat or umbrella, comfortable shoes, scarf for the breeze, light sweatshirt for the evening, especially in hill cities (see Kandy). From November to March, you can bring a light sweatshirt for the evening also in the plains, especially for the north-west. In Nuwara Eliya and at high altitudes, spring/autumn clothes, sweater and jacket for the evening, raincoat or umbrella.
For the reef, equipment for snorkeling, water shoes or rubber soled shoes.
Before entering temples, it is customary to remove shoes, dress neatly and cover a little.