Weather in Colombo 🇱🇰
Monthly weather averages & travel planning
May
Avg Temp
30°C
Rain Days
30 days
Sun Hours
9 hrs
Humidity
82%
Asia › 🇱🇰 Sri Lanka › Colombo
Updated: March 2026
Is May a Good Time to Visit Colombo?
4/10
Fair
May is a fair time to visit Colombo (4/10). With 9 daily sunshine hours and only 30 rain days, this month delivers genuinely reliable outdoor conditions, ranking it 7th sunniest of the year in Colombo. May suits travellers visiting for indoor culture, food, and architecture rather than outdoor activities. Pack accordingly for 30 potential rain days. June offers a similar profile at lower hotel rates if dates are flexible. Watch out for prolonged rain stretches: with 30 wet days, a fully outdoor itinerary is risky. Build in museum days and covered market visits as contingency. Planning tips: most accommodation categories have availability, and last-minute deals are common. The quieter streets and shorter queues can make this a genuinely enjoyable time to visit for the right type of traveller. Budget-conscious visitors will find the best value of the year in this period.
vs April:31°C avg high
Planning a trip to Colombo in May? Days warm to 30°C on average while evenings hold at 25°C, giving you a clear sense of what to pack. The month delivers roughly 9 hours of sunshine per day and 275mm of rainfall spread across 30 wet days, so there is plenty of fair weather to work with.
30°C
86°F
Avg High
25°C
77°F
Avg Low
30 days
275 mm total
Rain Days
9h
per day avg
Sunshine
82%
Humid
Humidity
Temperature in Colombo in May
The narrow 5°C gap between daytime and overnight temperatures, characteristic of coastal cities with maritime moderation, means a single mid-layer works across the whole day. At 82% humidity, the 30°C daytime high feels 2-4°C warmer in practice: quick-dry fabrics and shade-seeking between noon and 3pm are the sensible response. UV index averages 8 this month, classed as high to very high. SPF 30+ sunscreen, a brim hat, and sunglasses are not optional between 10am and 4pm. Wind averages 16 km/h, light enough to be refreshing on warm days but noticeable in open coastal areas or elevated viewpoints. In Fahrenheit: 86°F average high, 77°F overnight low. Data sourced from Open-Meteo ERA5 climate reanalysis (1991–2020 normals).
Temperature Trends
High
Low
Rainfall (mm)
0-20 mm21-50 mm51-100 mm100+ mm
What to Wear in Colombo in May
Morning25°CBefore the day warms up
Afternoon30°CPeak daytime temperature
Evening28°CAfter sunset cools down
Packing for Colombo in May means dressing for 30°C days and 25°C evenings. A lightweight linen or cotton shirt with loose-fit trousers or a sundress handles the 30°C daytime heat. Evening temperatures settle at 25°C, a modest 5°C drop that a light cardigan or denim jacket covers. For footwear, breathable walking sandals work for casual exploration, but closed-toe trainers are better for uneven surfaces in the historic centre. With 30 rain days expected, a compact travel umbrella is worth the bag space. A waterproof jacket is better than an umbrella if you plan full-day outdoor routes. For temple and religious site visits, carry a lightweight scarf or sarong to cover shoulders and knees, required at most major sites across the region. At 82% average humidity, quick-dry synthetic or bamboo fabrics dry overnight and stay comfortable longer than cotton.
Local tip: Loose-weave linen and moisture-wicking fabrics are the practical choice in Colombo's heat and humidity. Many shopping centres run air conditioning at near-arctic levels, so a thin layer in your bag prevents discomfort indoors.
Events in Colombo in May
May has no major festivals or public holidays in Colombo, which is one of its practical advantages for independent travellers. Attractions run at lower capacity than during peak event periods, queues are shorter, and accommodation is easier to find without needing to book many months in advance. Local restaurants, markets, and transport operate at a relaxed pace, making this an ideal time for visitors who prefer a more authentic, unhurried experience of everyday city life rather than large crowds drawn in by a single major headline event.
What to Pack for Colombo in May
Based on 30°C average highs and 30 rainy days
- Light layers for morning and evening
- Breathable T-shirts and comfortable trousers
- UV-protective sunglasses
- Quick-dry travel towel
- Anti-chafe balm for long walking days
- Moisture-wicking synthetic fabrics for active days
- Compact folding umbrella
- Waterproof outer layer or packable rain jacket
- Quick-dry clothing that recovers fast after a shower
- SPF 30+ sunscreen
- Comfortable walking shoes (a second pair lets the first air out overnight)
- Universal travel adapter
- Small day pack for city exploration
- Reusable water bottle
Best Activities in Colombo in May
- Early morning walk through Colombo's historic market districtBest before 9amTemperatures are still manageable at 26°C before the midday heat builds
- Open-air rooftop dining at sunsetFrom 6pm onwardsThe 30°C daytime heat drops noticeably after sunset, making al fresco dining comfortable
- Waterfront promenade or harbour walkEarly morning or after 5pmSea breezes cut through the humidity, making coastal routes the most pleasant in heat
- Guided cycling tour of the old quarterFirst tour of the day (7-9am)The low-traffic window before tourist crowds and the cooler morning air make this the prime riding slot
- Spend a morning in the national or city art museumOpens at 10am; arrive earlyWith 30 rain days expected, having a full-day indoor plan is practical insurance
- Cooking class focused on regional cuisineHalf-day sessions run 10am-1pm or 3-6pmIndoor activity that fills a rainy half-day with genuine cultural content
- Visit covered historical sites: cathedral, palace, or bazaarAny time; most crowded middayRoofed monuments and covered markets provide exploration without weather exposure
- Visit the main botanical garden or city park at seasonal peakYear-round; best light in morningMay brings distinct seasonal changes to public green spaces worth exploring
- Seek out chilled local specialities: cold-brew tea, ice desserts, or chilled seafood at street-level stallsAny time; most atmospheric in evening marketsHot-weather street food culture peaks in May, with vendors setting up specifically for warm evenings
Why is Colombo warm in May?
In May, Colombo sits in the dry season corridor, as the ITCZ shifts away from the region and trade winds bring drier, more stable air. This produces reliably sunny days reaching 30°C, with lower humidity than the wet months. Overnight lows of 25°C offer a pleasant reprieve from the midday heat. Climate data: Open-Meteo ERA5 (1991–2020).
Sunshine Hours
The average number of hours per day with direct sunlight. Calculated from satellite measurements. Days with more than 7 hours of sunshine are ideal for outdoor activities. Under 3 hours means overcast conditions dominate.
UV Index
A scale from 0-11+ measuring ultraviolet radiation intensity. UV 0-2: Minimal risk. UV 3-5: Moderate, wear sunscreen. UV 6-7: High, hat and SPF 30+ essential. UV 8-10: Very High, limit midday exposure. UV 11+: Extreme, seek shade between 10am-4pm.
Rain Days
A rain day is counted when precipitation exceeds 0.1mm. This threshold captures even light drizzle. Unlike total rainfall in mm, rain days tells you how often you might need an umbrella, which is useful for planning outdoor activities.
Humidity
Relative humidity as a percentage. Below 40%: Dry, skin and throat may feel parched. 40-60%: Comfortable, ideal for most people. 60-80%: Sticky, light breathable fabrics recommended. Above 80%: Muggy, heat feels more intense; quick-dry clothing is essential.
Frequently Asked Questions
Colombo in May
In May, Colombo experiences average highs of 30°C (86°F) and lows of 25°C (77°F). Expect around 30 rainy days and 9 hours of sunshine per day, with humidity averaging 82%. The 5°C gap between daytime and overnight temperatures is worth planning around: light layers work for most visitors during the day, but an overshirt or cardigan handles the cooler evenings. UV index averages 8, so sun protection is advisable on clear days.
Colombo typically sees 30 rainy days in May, with total precipitation of around 275mm. This is a notably wet period. A waterproof jacket or compact umbrella is essential, and it is worth building indoor alternatives into your daily itinerary for the inevitable rainy stretches. For context, the driest month in Colombo typically sees 4-6 fewer rain days than May.
Pack lightweight, breathable clothing (linen or cotton), a wide-brim sun hat, SPF 50+ sunscreen, and a refillable water bottle for Colombo in May. The 30°C daytime heat demands sun protection during midday hours, typically 11am to 4pm. A compact travel umbrella is also worth packing, as 30 rainy days means afternoon showers are a real possibility. Quick-dry synthetic fabrics are preferable to cotton in 82% humidity.
May is a reasonable time to visit Colombo. Expect 30 rainy days, so pack a light rain layer for flexibility. Average temperatures of 30°C make outdoor exploration comfortable during the dry periods. With 9 daily sunshine hours, there are reliable windows of good weather to plan outdoor activities around, even if the month is not the driest on the calendar.
The average high temperature in Colombo in May is 30°C (86°F), and the average low is 25°C (77°F). The mean daily temperature is approximately 28°C (82°F). The day-to-night range of 5°C is narrow, typical of coastal or maritime cities. These are 30-year climate normals based on the 1991 to 2020 reference period; individual years will vary, particularly in transitional months like spring and autumn.
The best month to visit Colombo is generally January. January offers the most sunshine at 11 hours per day and only 9 rainy days. Average temperatures reach 30°C, making it comfortable for sightseeing, outdoor dining, and exploring the city. If your travel dates are flexible, planning your trip around January gives you the best chance of dry, bright weather.
May is shoulder or low season in Colombo, meaning fewer tourists and generally lower prices than peak months. With 9 sunshine hours and 30 rainy days, the weather is less of a draw for mass tourism. This is an advantage for travellers who prefer a quieter, more relaxed experience with shorter queues and easier accommodation availability.
In May, Colombo suits a range of activities thanks to warm temperatures of 30°C. With frequent rain, indoor activities and covered attractions are a smart choice. Top options include exploring historic neighbourhoods, visiting museums and galleries, local food markets, and day trips to surrounding areas. With 9 hours of sunshine, parks and waterfront walks are particularly enjoyable.
May ranks 7th sunniest of the year in Colombo, with an average 9 daily sunshine hours. The driest months are January, February, and March. February is the hottest month (31°C avg high); July is the coolest (28°C). From here, temperatures fall 1°C into June. Compared to last month (April: 31°C high, 26 rain days), May is cooler and wetter. May sits in the middle of the annual sunshine ranking for Colombo, offering a reasonable balance of good weather and manageable crowds.
Year-Round Climate
| Month | High | Low | Rain Days | Sun | Details |
|---|---|---|---|---|---|
| January | 30°C | 23°C | 9 | 11h | View |
| February | 31°C | 23°C | 9 | 11h | View |
| March | 31°C | 24°C | 16 | 11h | View |
| April | 31°C | 25°C | 26 | 10h | View |
| May | 30°C | 25°C | 30 | 9h | View |
| June | 29°C | 25°C | 29 | 9h | View |
| July | 28°C | 25°C | 29 | 10h | View |
| August | 28°C | 25°C | 29 | 10h | View |
| September | 28°C | 24°C | 28 | 9h | View |
| October | 29°C | 24°C | 28 | 9h | View |
| November | 29°C | 23°C | 24 | 8h | View |
| December | 29°C | 23°C | 16 | 9h | View |
January
9 rain days, 11h sun
30°23°
February
9 rain days, 11h sun
31°23°
March
16 rain days, 11h sun
31°24°
April
26 rain days, 10h sun
31°25°
May
30 rain days, 9h sun
30°25°
June
29 rain days, 9h sun
29°25°
July
29 rain days, 10h sun
28°25°
August
29 rain days, 10h sun
28°25°
September
28 rain days, 9h sun
28°24°
October
28 rain days, 9h sun
29°24°
November
24 rain days, 8h sun
29°23°
December
16 rain days, 9h sun
29°23°
Other Months in Colombo
Plan Your Trip to Colombo
Data Sources for Colombo
Climate normals represent 30-year averages (1991-2020). Individual years may vary.