May Weather in Colombo, Sri Lanka

Last updated: March 19, 2025

In Colombo, Sri Lanka, May unveils a tropical paradise characterized by warm temperatures and a vibrant atmosphere. With maximums soaring to 32°C (90°F) and an average around 28°C (83°F), the days are filled with warmth, while evenings offer a gentle respite at a minimum of 25°C (78°F). However, this month also brings significant precipitation, with a whopping 295 mm (11.6 in) of rainfall spread across 29 days, creating a lush, green landscape. Accompanied by a notable humidity level of 76%, May is a time when Colombo's natural beauty thrives, inviting visitors to embrace the unique charm of its rainy season.

May Temperature in Colombo

In Colombo, Sri Lanka, May marks the transition into the warmer months, showcasing a minimum temperature of 25°C (78°F) and a comfortable average of 28°C (83°F). With a peak temperature reaching around 32°C (90°F), the city experiences a slight decline compared to the preceding months, hinting at the onset of seasonal changes. This pattern of consistent warmth, with minimal fluctuations in temperature, highlights the tropical charm of Colombo, making May an inviting time for visitors to explore its vibrant culture and stunning landscapes. As the city prepares for the approaching rains, the warm and humid atmosphere sets the stage for lush greenery and lively festivities, ensuring that the allure of Colombo remains high throughout the month.

May Weather in Colombo: Daily Temperature Highs, Lows, and Averages

The chart illustrates May temperature patterns in Colombo, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec818283838382828181818181
Data source: Temperature data for Colombo generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

May Precipitation in Colombo

May marks a significant shift in Colombo's precipitation pattern, as the city experiences its heaviest rainfall of the year, accumulating 295 mm (11.6 in) over 29 days. This surge dramatically surpasses the rainfall of both April and March, reflecting a ramping up of the monsoon season. As temperatures rise and humidity increases, May's rain provides a refreshing contrast, rejuvenating the lush landscapes that surround the bustling city. Following this trend, June continues the wet spell with 257 mm of rain, hinting that the monsoon's impact lingers well into early summer, emphasizing the importance of May as a pivotal month in Colombo's climatic calendar.

May Precipitation Trends in Colombo

The chart displays monthly precipitation patterns in Colombo, with values for each month alongside May's data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how May's conditions compare to those of other months.
JanFebMarAprMayJunJulAugSepOctNovDec5454118126295257168189234347294179
Data source: Precipitation data for May generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

May Humidity in Colombo

May in Colombo, Sri Lanka, brings a slight dip in humidity to 76%, just below the peaks seen in the preceding months. Following the high humidity of April, which also lingered at 74%, May serves as a gentle transition into the more humid months of June and July, both averaging 82%. This consistent level of humidity throughout the early months of the year, ranging from 73% to 77%, indicates a warm and moist tropical climate setting the stage for what is to come. As the year progresses into the latter months of summer, the humidity continues to rise, reaching its zenith in late summer and early fall, suggesting that while May may offer a brief respite, the tropical humidity of Colombo is ever-present and prepares for a humid embrace in the months ahead.

May Average Humidity in Colombo

This chart illustrates the average monthly humidity levels in Colombo, with May's data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, allowing you to see how May's humidity levels compare to other months.
JanFebMarAprMayJunJulAugSepOctNovDec77%73%74%74%76%82%82%83%82%81%80%80%
Data source: Humidity data for May generated using information from the Copernicus Climate Change Service.

May UV Index in Colombo

In May, Colombo experiences a notable UV Index of 14, categorized as extreme, maintaining the same level as both February and March. This consistency underscores a trend of relentless sun exposure as the region transitions into its warmer months. With a burn time of just 10 minutes, outdoor enthusiasts should exercise caution during this time, as the risk of skin damage remains high. Following May, the UV Index slightly decreases, but it is crucial to stay vigilant. For more detailed information on UV levels throughout the year, check out Colombo UV Index.

Maximum UV Index Levels in Colombo for May

The chart shows the monthly maximum UV Index (UVI) for Colombo in May, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues.
JanFebMarAprMayJunJulAugSepOctNovDec121414151413131314131110
Data source: Colombo May UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

May Sunshine in Colombo

May brings a delightful 312 hours of sunshine to Colombo, Sri Lanka, consistent with the sunshine experienced in February and December. As part of a gradual transition from the radiant summer months, May’s hours slightly dip from the highs of March and April but remain robust, providing ample opportunity for outdoor adventures. The sunlit days of this month continue a trend of plentiful sunshine seen from January through July, where each month yields over 300 hours. This pattern reflects Colombo's overall tropical climate, ensuring that even as the wet season approaches, the warmth and brightness linger, inviting both locals and visitors to revel in the island's scenic beauty.

Monthly Sunshine Duration in Colombo: May Highlighted

The May sunshine duration represents the total number of hours Colombo experiences direct sunlight during the month of May, excluding cloudy or obstructed periods. This chart compares the sunshine duration of May with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec270h312h336h334h312h320h333h326h304h299h279h312h
Data source: Colombo May Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Colombo During May

As one browses through the likelihood of sunny weather in Colombo, Sri Lanka, May emerges as a particularly cloudy month, presenting only a 17% chance of sunshine. This trend showcases a noticeable dip compared to April's more favorable 46%. In stark contrast, February reigns supreme with a 53% chance, while December also shines brightly, reflecting a robust 54% likelihood of sunny skies. As the year progresses, particularly through the monsoon months from May to August, the chances of clear weather diminish significantly, reinforcing the notion that May may not be the ideal time for sun-seekers in this vibrant coastal city. With the early months hinting at sunnier prospects, it's clear that planning a visit during the peak sunny months can greatly enhance one’s experience in Colombo.

Percentage of Sunny Days in May in Colombo

The chart illustrates the percentage of sunny days in Colombo throughout the year, with May highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Colombo experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec22%53%32%46%17%21%15%9%18%15%14%54%
Data source: Colombo May chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Colombo in May

In Colombo, Sri Lanka, May marks a delightful period where daylight reaches a steady 12 hours, continuing the trend established in April and embracing the consistency that characterizes the subsequent months of June through September. This stable duration of daylight paints a picture of an inviting climate, encouraging outdoor activities and vibrant city life. As the year progresses into October, the daylight begins to taper off, returning to 11 hours; however, this subtle shift is hardly noticeable amidst the ongoing enjoyment of the lush beauty and cultural richness that Sri Lanka offers throughout the sunny May days.

Average Daylight Hours in Colombo for May

The chart illustrates the variation in daylight duration in Colombo throughout the year, with May highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec11h 45m11h 53m12h 4m12h 15m12h 25m12h 30m12h 27m12h 19m12h 8m11h 57m11h 47m11h 43m
Data source: Colombo daylight hours, calculated by summing the hours between sunrise and sunset for each day.

May Winds in Colombo

In May, Colombo, Sri Lanka experiences a noteworthy uptick in wind speed, averaging 4.4 m/s (10 mph), providing a refreshing breeze as the region transitions deeper into the monsoon season. Compared to April's gentler winds at 3.0 m/s (7 mph), May presents a delightful change, hinting at the strengthening patterns leading into June, which peaks at 5.1 m/s (11 mph). This gradual escalation reflects a broader trend of increasing winds throughout the upcoming months, culminating in the summer's bluster. Overall, May serves as a charming prelude to the vibrant winds of the following months, crafting a dynamic atmosphere that both locals and visitors can enjoy.

Average May Wind Speed in Colombo

The chart displays monthly wind speed patterns in Colombo, with values for each month shown alongside May's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how May's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec3.54.72.33.04.4 m/s5.15.65.34.93.93.83.9
Data source: Colombo May wind data, generated using information from the Copernicus Climate Change Service.

How May Weather in Colombo Compares to Other Months

The weather in Colombo changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of May's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Colombo and find detailed weather information for every month.

In comparing the weather of May and January, May typically experiences warmer temperatures, with averages around 28°C (83°F) and maxima reaching 32°C (90°F), while January offers a slightly cooler average of 27°C (81°F) and maxima peaking at 33°C (92°F). However, May is significantly wetter, receiving about 295 mm (11.6 in) of precipitation over 29 days, compared to January's milder 54 mm (2.1 in) over just 7 days. Both months feature high humidity levels, with May at 76% and January slightly higher at 77%. This makes January a potentially more pleasant option for outdoor activities given its lower rainfall and mild conditions. For more detailed insights, you can check Colombo weather in January.

In comparing the weather between May and February, May typically presents warmer conditions, with average temperatures ranging from 25°C (78°F) to a maximum of 32°C (90°F), while February's temperatures are slightly cooler, averaging between 22°C (73°F) and reaching up to 34°C (94°F). May experiences significantly more rainfall, with about 295 mm (11.6 in) over a total of 29 days, compared to February's much lighter precipitation of 54 mm (2.1 in) spread over 9 days. Humidity levels remain relatively similar, with May at 76% and February at 73%. For more details on February's climate, you can check Colombo weather in February.

In comparing the weather between March and May, both months exhibit warm temperatures, with March showing a slightly lower maximum average of 33°C (92°F) compared to May's maximum of 32°C (90°F). However, May is notable for its higher overall humidity at 76% and significantly more rainfall, totaling 295 mm (11.6 in) over 29 days, in contrast to March's 118 mm (4.6 in) across just 17 days. For a detailed insight into March's conditions, you can visit Colombo weather in March.

In comparing the weather between April and May, both months maintain similar temperatures with minimums around 25°C (77°F to 78°F) and average highs near 28°C (83°F). However, May experiences slightly higher humidity at 76% compared to April's 74%. One notable difference is in precipitation: May has significantly more rainfall, totaling 295 mm (11.6 in) over 29 days, while April records just 125 mm (4.9 in) over 25 days. For a closer look at April's conditions, you can visit Colombo weather in April. Overall, May tends to bring more rain and humidity, making it feel more tropical than April.

In comparing the weather between May and June, both months experience similar temperature ranges, with minimums at 25°C (78°F) and average highs of around 28°C (82°F to 83°F). However, May is slightly warmer, reaching a maximum of 32°C (90°F) compared to June's 31°C (87°F). Precipitation levels are also noteworthy; May sees a higher amount with 295 mm (11.6 in) over 29 days, while June has 257 mm (10.1 in) over 28 days. Additionally, humidity increases slightly in June to 82%, up from May's 76%. For more details on the weather conditions in June, you can check Colombo weather in June.

In May, the weather tends to be quite humid, with average temperatures hovering around 28°C (83°F) and a maximum reaching up to 32°C (90°F). The month is marked by significant precipitation, totaling 295 mm (11.6 in) spread over 29 days, which contributes to a moisture-laden atmosphere with humidity levels at 76%.

In contrast, July experiences slightly cooler temperatures, with averages around 28°C (82°F) and a maximum of 30°C (87°F). While still humid at 82%, July sees considerably less rainfall, with 168 mm (6.6 in) of precipitation over 26 days. This reduction in rain leads to a drier feel compared to May. For more detailed insights, you can check Colombo weather in July.

In May, the weather tends to be warmer with an average temperature of 28°C (83°F) and peaks reaching 32°C (90°F). This month experiences significant rainfall, totaling 295 mm (11.6 in) across 29 days, accompanied by a humidity level of 76%. In contrast, August offers slightly cooler conditions, with an average temperature of 27°C (81°F) and a maximum of 30°C (85°F). The rainfall in August is considerably lower at 189 mm (7.4 in) over 27 days, though humidity rises to 83%. For more details, you can check Colombo weather in August.

In May, the weather is characterized by higher temperatures, with a minimum of 25°C (78°F), an average of 28°C (83°F), and a maximum of 32°C (90°F). The month experiences substantial rainfall, averaging 295 mm (11.6 in) over 29 days, accompanied by a humidity level of 76%. In contrast, September sees slightly cooler conditions, with temperatures ranging from a minimum of 25°C (77°F) to an average of 27°C (81°F) and a maximum of 30°C (86°F). Precipitation decreases to 234 mm (9.2 in) across 26 days, although humidity rises to 82%. For more detailed insights on the weather in September, visit Colombo weather in September.

When comparing the weather in May and October, both months experience relatively high temperatures, with May having a slightly higher average of 28°C (83°F) compared to October’s 27°C (81°F). However, October tends to be wetter, with precipitation totaling 347 mm (13.6 in) compared to May’s 295 mm (11.6 in). Both months have the same frequency of rainy days, occurring on 29 days, though October has a higher humidity level at 81%, compared to May’s 76%. For more detailed insights on the weather conditions in October, you can refer to Colombo weather in October.

May and November in Colombo exhibit quite similar weather patterns, with average temperatures hovering around 28°C (83°F) in May and slightly cooler at 27°C (81°F) in November. Both months experience high humidity levels, with November having a marginally higher humidity at 80% compared to May's 76%. Precipitation levels are also similar, with May receiving about 295 mm (11.6 in) over 29 days and November seeing just a slight decrease at 294 mm (11.6 in) over 26 days. For a deeper dive into November's specific conditions, you can check out Colombo weather in November.

May and December exhibit distinct weather characteristics in Colombo. In May, temperatures range from a minimum of 25°C (78°F) to a maximum of 32°C (90°F) with an average of 28°C (83°F). This month experiences significant rainfall, totaling 295 mm (11.6 in) across 29 days, along with a humidity level of 76%. In contrast, December offers slightly cooler temperatures, with a minimum of 23°C (73°F) and an average of 27°C (81°F), peaking at 32°C (89°F). Rainfall in December is considerably lower at 179 mm (7.1 in) over 17 days, accompanied by a higher humidity level of 80%. For more insights on December weather patterns, visit Colombo weather in December.

Compare Colombo's Climate with Cities Worldwide

Conclusion: What to Expect From May Weather in Colombo

As May settles in over Colombo, the weather transforms into a rainy tapestry, with increased humidity and nearly a month-long stretch of precipitation. While temperatures remain warm, with averages around 28°C, the frequent downpours significantly distinguish this month from the drier spells of neighboring months. This makes May one of the wettest periods in the city, setting the stage for lush landscapes and vibrant greenery. If you're curious about how these weather patterns shape the overall climate of the region, be sure to explore Colombo Climate for more insights.