Sri Lanka in December: weather, where to go and what to wear

December is when the island flips. The stormy changeover of November gives way to the northeast monsoon, which pours its rain on the north and east and leaves the south and west coasts with the driest, calmest weather they have had all year. That makes it the start of high season, and the question is simple: stay on the right side of the island, and pack for strong sun on the beach and cold dawns in the hills.

Colombo day

30°C

Colombo night

22°C

Rain (Colombo)

~170 mm

Sea

28°C

What the weather is really like in December

The Department of Meteorology counts December as the first month of the northeast monsoon, which runs until February. Its rain falls mainly on the Northern, North Central, North Western, Eastern and Uva provinces. Thunderstorms become less frequent than in the inter-monsoon months, so the rain is steadier in the east and much rarer in the southwest.

Colombo is a good example of the change. It averages about 170 mm of rain in December, roughly half of what it gets in November, spread over around 10 days, with about seven hours of sunshine a day. It is not bone dry, and early December can still bring a shower on the south coast, but most days are bright. The sea stays at 28°C and the UV index reaches an extreme 11, so sunburn is a bigger risk than rain.

The hill country is the cool exception. Nuwara Eliya sees around 19°C by day and 12°C at night, and clear December nights can feel colder than that at altitude. Ella sits in Uva province, on the side of the hills that catches the monsoon, so expect more cloud and showers there than on the coast.

Region by region

Where to go in December

Build the trip around the south coast. Fort walls in Galle, swimming bays at Unawatuna and whale-watching boats from Mirissa, which have their best sightings from December to April, all come into their own now. Add a few days inland for Sigiriya and the Dambulla cave temples, climbing in the early morning before cloud or heat build, then head to the hills for tea country.

Christmas and New Year are the busiest and most expensive weeks of the year. If you are travelling between about 20 December and early January, book trains, safaris and south-coast rooms well ahead.

What to wear in December

For strong sun on the coast

With a UV index of 11, covering up works better than sunscreen alone. A loose long-sleeved linen shirt keeps the sun off and stays cool, and a wide-brimmed hat and good sunglasses do more than another swimsuit. Sunburn in the first two days is the most common way to spoil a December beach trip. Keep swimwear for the beach: in Galle Fort, shops and restaurants, put on a shirt or tie on a sarong.

For evenings

Sri Lanka is relaxed, but Christmas and New Year dinners at south-coast hotels are a little dressier. One smart linen outfit is enough, and sandals are fine almost everywhere. Evenings by the sea are warm, so you will not need a jacket below the hills.

Climbing Adam's Peak in December

December is the month the pilgrimage season on Adam's Peak (Sri Pada) begins. It traditionally opens on Unduvap Poya, the December full moon, when sacred objects are carried up the mountain, and runs until Vesak in May. The dates for the 2026–27 season had not been announced at the time of writing, so check them before you plan around it. Once it opens, the path is lit, tea stalls open and pilgrims climb through the night to reach the 2,243 m summit for sunrise.

Dress for two climates in one night. You will sweat on the steps, then stand still in a cold wind at the top, so wear layers you can take off and carry a warm jacket for the summit. This is a sacred site for Buddhists, Hindus, Muslims and Christians alike, so cover your shoulders and knees, and take off your shoes and hat at the sanctuary at the top.

Temple and church dress code

At Buddhist temples, including the Temple of the Tooth in Kandy, cover your shoulders and knees and take off your shoes and hat before you enter. Visitors in shorts or sleeveless tops can be refused entry there. The UK Foreign Office travel advice also warns against posing for photos with your back to a Buddha statue, which is treated as a serious offence. Our November guide covers the rules at kovils and mosques too.

Sri Lanka's Catholic community is largest along the west coast, especially around Negombo. If you go to a Christmas service, dress as you would for a temple: covered shoulders and knees, with light, smart clothes. White is a safe choice at both.

Festivals and holidays in December 2026

• Unduvap Full Moon Poya — Wednesday 23 December. Listed in the government's 2026 holiday calendar. It marks the arrival of the sacred Bo tree sapling in Sri Lanka. Temples are crowded with people in white, sales of alcohol and meat are banned for the day, and many bars close.
• Christmas Day — Friday 25 December. A public holiday. Colombo's shopping streets and hotels are decorated, and midnight services are held at churches around Negombo and Colombo.

December packing list

• 4–6 loose cotton or linen tops, including one long-sleeved shirt for sun protection
• Light trousers or long skirts that work for temples, plus shorts for the beach
• A sarong or large scarf for temple cover-ups and beach wraps
• A fleece and a light waterproof jacket for the hills
• Sun hat, sunglasses and high-factor sunscreen
• Sandals with grip, and closed shoes for walks and Adam's Peak
• Swimwear and a cover-up
• One smarter outfit for Christmas or New Year dinners
• Insect repellent for evenings