Best Time & Weather

Sri Lanka Weather by Month: 2026 Temperature Guide

Pubudu Dissanayaka

October 26, 2026

16 Min Read

9 Views

0 Comments

Last updated: 26 October 2026 | Written by Pubudu Dissanayaka, founder of CeylonFarer

Sri Lanka weather by month is not one climate. It is four, and they peak in different months on opposite sides of the island. We took ten years of daily readings for twelve places people actually stay in, then turned them into one mean for every month of the year.

The numbers below are ours. They come from the Open-Meteo historical archive for January 2016 to December 2025, and we checked four of the twelve places against the Department of Census and Statistics own station table. Where the two disagree, we say so and give both figures.

The short version: not one of our twelve places is hottest in January, and none is hottest in December. The island mean daily maximum peaks in April at 30.2 °C and bottoms out in December at 27.4 °C. The east coast runs 7.0 °C hotter in June than in January while the south coast moves 2.2 °C all year.

Which months are hottest in Sri Lanka?

April is the hottest month nationally, with a mean daily maximum of 30.2 °C across the twelve places we measured. December is the coolest at 27.4 °C. That national average hides most of what matters, because it mixes a hill station at 1,888 metres with a beach at sea level.

Sri Lanka weather by month only becomes useful once you split the island up. Our twelve places peak in five different months, and the groups are not the ones travel copy usually names.

• February: Colombo, Negombo and Mirissa (3 places)
• March: Galle and Kandy (2 places)
• April: Jaffna, Anuradhapura and Nuwara Eliya (3 places)
• June: Trincomalee, Arugam Bay and Batticaloa (3 places)
• July: Ella (1 place)

Sri Lanka weather by month is really five peak months, not one.

That leaves seven months in which no place we measured is at its hottest. If a page tells you Sri Lanka is hottest in April and stops there, it is describing an average and not a place. Anuradhapura sits at 33.9 °C in April against Trincomalee at 34.7 °C in June.

Which coast is hottest, and in which month?

Sri Lanka weather by month divides the island along the ridge, and the two sides behave differently enough that they need separate answers.

The west and south coast have almost no summer. The east coast has a fierce one. The hill country has a mild version of the east coast pattern, and it arrives in July rather than June.

The west and south coast barely move

Colombo runs from a mean daily maximum of 28.4 °C in August to 31.4 °C in February, a spread of 3.0 °C. Negombo spreads 3.4 °C and Galle just 2.2 °C, from 28.3 °C in August to 30.5 °C in March. The sea keeps the air on a short leash here.

Sri Lanka weather by month on this coast is a rain question, not a heat one. Nights move more than days do, from 22.7 °C in January to 25.4 °C in May, and that is the change you notice in a room without air conditioning.

The east coast has a seven-degree summer

Trincomalee climbs from 27.7 °C in January to 34.7 °C in June. That is a 7.0 °C swing, more than twice the south coast total for the whole year. Batticaloa swings 6.8 °C and Arugam Bay 5.9 °C, both peaking in the same month.

Sri Lanka weather by month has its widest swing on this coast, and it lands in the months most people book for the beaches.

This flips the coast you would pick. January gives you the coolest air of the Trincomalee year at 27.7 °C and the wettest weather of its year at 22.6 rain days. June gives you the hottest air at 34.7 °C and the driest at 8.9 rain days. Same beach, opposite trade-off.

Jaffna and the north peak in April

Jaffna runs 28.1 °C in January to 32.3 °C in April, a 4.2 °C spread. Anuradhapura is wider at 5.2 °C, from 28.7 °C in December to 33.9 °C in April. Both peak two months before the east coast does, and both dry out earlier.

Nights in the north are the story. Jaffna moves from 23.5 °C in January to 27.9 °C in May, the widest night swing of the twelve places, so a February night there is genuinely cooler than a May one.

Ella is hottest in July, which surprises people

Ella at 907 metres climbs from 23.7 °C in January to 27.7 °C in July. July is the wettest month on the south coast and the hottest month at Ella, because the southwest monsoon drops its rain on the windward side and leaves the lee of the ridge warm and clear.

Nuwara Eliya at 1,888 metres is a different world. Its warmest month is April at 21.3 °C and its coolest is January at 18.7 °C, and its mean night low runs 11.5 °C in January against 21.8 °C for Kandy in June. Seven degrees separate Kandy from Nuwara Eliya in the same week of the year.

Sri Lanka weather by month, region by region, comes down to this table. Read the Trincomalee column and the Galle column together and you can see one coast heating up while the other barely shifts.

How much hotter does it feel than the thermometer says?

Humidity is the part of Sri Lankan heat that a temperature table cannot show. We calculated the mean daily maximum apparent temperature, which folds humidity and wind into the air temperature, and subtracted the plain maximum from it. The difference is the humidity tax.

Sri Lanka weather by month is misleading without this column, because air temperature is the number a thermometer reports and apparent temperature is the number your body works with.

Every region pays it hardest in April. The west and south coast adds 6.4 °C, the east coast 6.3 °C, the north 5.9 °C and the hill country 3.7 °C. The single worst cell in ten years of data is Anuradhapura in April, where 33.9 °C of air feels like 39.5 °C.

Anuradhapura in April averages 33.9 °C and feels like 39.5 °C. That gap of 5.6 degrees is the difference between a sightseeing day and a sit-down day.

CeylonFarer measurement, 2016-2025

Reading a sri lanka climate chart properly

A sri lanka climate chart is normally a line of monthly averages with no humidity layer, which makes April look only slightly worse than March. Ours says April is the worst month to walk around a ruin in, because the apparent temperature peaks then on every coast at once.

Sri Lanka weather by month read without humidity will send you to Anuradhapura in April on a 34 degree forecast.

The hill country is the exception in the other direction. Its gap never exceeds 3.7 °C and falls to 2.1 °C in July, so the air there feels close to what the thermometer reports. That is one reason the tea country is bearable in months the coast is not.

How many days does it rain each month?

Millimetres tell you how wet a month is. Rain days tell you what a month does to your plans. We counted every day with at least 1 mm of precipitation, averaged by calendar month, over the same ten years. Light drizzle counts, so these numbers run higher than the days you would actually cancel something for.

Rain days are the half of Sri Lanka weather by month that millimetres hide, because 200 mm in four storms leaves you a dry week and 200 mm in twenty drizzles does not.

The west and south coast goes from 12.8 rain days in February to 29.3 in May. The east coast goes the other way, from 8.9 in June to 25.2 in November. The north is the driest region in its dry window at 6.0 rain days in February, and the hill country peaks in October at 25.4 rather than in the monsoon months.

If you want the millimetres and the coast-by-coast detail, we published those separately in our guide to which coast gets the rain, month by month. This page stays with days and degrees.

Sri Lanka weather by month in rain days is a different table from the one most guides print.

How we measured Sri Lanka weather by month

We did not collect these figures from a blog. We pulled the daily archive for twelve places from the Open-Meteo historical weather API, which serves the ERA5 and ERA5-Land reanalyses maintained by the European Centre for Medium-Range Weather Forecasts. The window is 1 January 2016 to 31 December 2025, which is 3,653 days per place in the Asia/Colombo timezone.

Everything on this page is Sri Lanka weather by month measured from that archive, not recalled from a visit.

Every daily maximum and minimum was bucketed into its calendar month, and each month is the plain arithmetic mean of those daily values across the ten years. The apparent temperature uses the same reanalysis fields, so the gap in the table above is a real modelled difference rather than an estimate of one. The API schema is documented at the Open-Meteo historical weather API.

Two limits matter. A reanalysis is a model on a grid roughly 9 km across, not a thermometer in a Stevenson screen, so a coastal town is represented by the grid cell it falls in. And these are means, not forecasts: a single April day in Colombo can beat 34 °C while the April mean maximum is 31.1 °C. We rewrote this page on 26 October 2026 and every figure on it comes from the same run.

What is each month like, in plain words?

Sri Lanka weather by month, taken one month at a time, is the shortest useful version of everything above.

Twelve short sections, one per month, using the tables above. Each one names the finding that matters for that month rather than repeating the whole grid.

January: the coolest nights on the coast

January is the coolest month for nights on the west and south coast, at 22.7 °C in Colombo and Galle. It is also the coolest month of the year for Trincomalee at 27.7 °C, which is not what most people expect of the east coast. Rain days run 13.3 in Colombo and 8.8 in Jaffna.

Sri Lanka weather by month starts with the coolest nights of the year.

February: the hottest fortnight on the west coast

Sri Lanka in February is the driest month of the west coast year by rain days, 12.8 against 29.3 in May, and the hottest by air temperature, 31.4 °C in Colombo and 31.9 °C in Negombo. Jaffna drops to 4.8 rain days, the driest month anywhere in our dataset.

On the west coast, Sri Lanka weather by month peaks here.

March: Galle and Kandy reach their peak

March is when the south coast and the central hills top out, at 30.5 °C in Galle and 31.0 °C in Kandy. Humidity is still low by local standards, 73.0 per cent in Kandy, so the same temperature feels easier than it will in April.

Sri Lanka weather by month turns before the April heat arrives.

April: the whole island peaks together

April is the hottest month nationally at a mean daily maximum of 30.2 °C, and the month with the largest humidity tax everywhere, up to 6.4 °C on the west coast. Anuradhapura feels like 39.5 °C. Rain days climb to 19.9 nationally as the inter-monsoon starts.

Sri Lanka weather by month is at its hottest in April.

May: the west coast gets wettest by rain days

May is the wettest month of the year on the west and south coast by rain days, 29.3, and the month the southwest monsoon arrives. Air temperatures already ease, 29.8 °C in Colombo against 31.4 °C in February, so the month is wet rather than hot.

Sri Lanka weather by month hands the south coast to rain in May.

June: the east coast takes over

June is the east coast peak and the main reason Sri Lanka weather by month is a two-coast question. Trincomalee and Batticaloa both hit 34.7 °C while Colombo cools to 28.9 °C, and Trincomalee sees only 6.2 rain days, its driest month.

Sri Lanka weather by month crosses the island in June.

July: Ella is at its hottest

July is Ella at 27.7 °C, four degrees above its January figure, because the southwest monsoon has already spent its rain on the windward side. The east coast stays hot and dry, and its humidity drops to the lowest of its year at 66.8 per cent in Trincomalee.

August: the coolest air on the south coast

Sri Lanka in August gives the west and south coast its coolest mean maximum of the year, 28.4 °C in Colombo and 28.5 °C in Negombo, and the smallest humidity tax at 4.5 °C. Rain days stay high at 27.5 on the west coast while the east runs 12.4.

Sri Lanka weather by month is at its mildest on the south coast in August.

September: the quiet month before the change

September is the last month of the east coast season and the point where the national mean maximum bottoms out at 29.3 °C before October. Rain days are climbing on both coasts, 27.5 in the west and 15.0 in the east, and Mirissa records its coolest month at 28.7 °C.

Sri Lanka weather by month holds steady through September.

October: the hill country gets its wettest month

October is the wettest month of the year in the hill country by rain days, 25.4, and the month the inter-monsoon delivers its afternoon storms. The national mean maximum falls to 28.4 °C, the first real drop since April.

Sri Lanka weather by month turns wet inland in October.

November: everywhere is at its most humid

November is the most humid month at all twelve places we measured, from 84.6 per cent in Jaffna to 89.9 per cent in Nuwara Eliya. Rain days peak on the east coast at 25.2 and in the north at 24.2, and the national mean maximum drops to 27.5 °C.

Sri Lanka weather by month is at its most humid in November.

December: the coolest month nationally

December has the lowest national mean daily maximum of the year at 27.4 °C, and the west coast dries out fast, from 24.7 rain days in Colombo in November to 18.1. The east coast is still wet at 22.6 rain days, which is why a December beach holiday belongs in the west.

Sri Lanka weather by month is at its coolest nationally in December.

Which month should you avoid, and which should you book?

Sri Lanka weather by month is a booking decision, not trivia.

Avoid April if heat is the problem. It is the hottest month nationally and the month with the largest humidity tax on every coast, with Anuradhapura at 39.5 °C apparent and Batticaloa at 38.3 °C. Avoid November if humidity and rain days are the problem, because it is the most humid month at all twelve places and the wettest by rain days on the east coast and in the north.

Book February for the west and south coast: 12.8 rain days and 31.4 °C in Colombo. Book June or July for the east: 34.7 °C and 6.2 rain days in Trincomalee. Book January for the hill country if you want the coolest nights, 11.5 °C in Nuwara Eliya, and April if you want the driest air up there at 77.6 per cent humidity.

sri lanka weather safety, in numbers

Sri Lanka weather safety is mostly heat management. The apparent temperature passes 38 °C in seven of our twelve places in their peak month, so treat 11:00 to 15:00 as indoor time in April and May on the lowlands. Signs of heat exhaustion arrive before you feel thirsty, and the humidity that produces those numbers also stops sweat from doing its job.

Sri Lanka weather by month is also the reason the hill country needs a jacket while the coast needs shade.

The hill country has the opposite risk. Nuwara Eliya averages 11.5 °C at night in January and 13.0 °C in November, and the humidity there is the highest we measured at 89.9 per cent, so cold and wet arrive together. Take a real jacket for the hills in any month, and take it for the early morning.

Does the government own table agree with our numbers?

Sri Lanka weather by month holds up against the department own station table, which is the test that matters for numbers we calculated ourselves.

Our measurement is a model on a grid. The Department of Census and Statistics publishes measured station values in its Statistical Abstract, Table 1.4, which gives monthly average minimum and maximum air temperature at observation stations for 2020 to 2023. We parsed the 2023 block and compared it with our ten-year means.

Four stations parsed cleanly and all four agree within 1.6 °C. Jaffna is the widest at +1.6 °C on the maximum and -0.5 °C on the minimum. Anuradhapura sits at +1.2 and +0.6, Nuwara Eliya at +0.8 and -0.2, and Galle at +0.9 and +1.0. A single year against a ten-year mean should drift by a degree or so, and that is what we see.

Colombo and Trincomalee are missing from that table on purpose. The 2023 block of the source PDF prints a placeholder instead of a value for one month at each of those two stations, and we will not average around a hole. The full table is at Table 1.4 of the Statistical Abstract 2024.

We spot-checked humidity the same way. Table 1.5 of the same abstract gives Colombo January 2023 as 69 per cent by day and 83 per cent at night. Our ten-year January mean for Colombo is 78.1 per cent, which lands between those two as it should for a daily mean. That table is at Table 1.5, annual and monthly average relative humidity.

What we could not verify

Sri Lanka weather by month still has one official gap we could not close.

The Department of Meteorology site did not respond on 26 October 2026. We tried meteo.gov.lk over https from two hosts and both timed out after 25 seconds, so we did not re-read the department own season calendar and we have not linked it here. If it comes back, it belongs beside Table 1.4 as a second official check.

Sri Lanka weather by month is complete on temperature and rain days, thinner on everything else.

We did not measure sea temperature, UV index, or lightning frequency, and we did not buy station normals beyond the 2020 to 2023 window the abstract publishes. Anything in this guide that is not in the tables came from arithmetic on those tables.

Frequently asked questions about Sri Lanka weather by month

These are the questions the live search results put in front of readers, answered from the tables above rather than from impressions.

Where to go next

If you now know which month you want, the next question is whether the route fits it. Our month-by-month guide to planning a Sri Lanka route takes the same seasons and turns them into day counts, and the three-week loop is built around the coast that is dry when you land.

On Sri Lanka train vs bus, the short answer from this data is that the train is the comfortable choice in the dry months and the bus is the reliable one in the wet ones. Our getting around Sri Lanka guide covers the fares, and the ETA is the one thing to sort before you book anything.

Sri Lanka weather by month decides the route as much as it decides the coast.

For the rain in millimetres rather than in days, read the monsoon guide. For the short version of when to go, read the best time to visit guide. Everything else we publish sits in our full index of Sri Lanka guides.