April Weather in Ko Samui, Thailand

Last updated: August 27, 2025

April in Ko Samui, Thailand, is characterized by warm tropical weather, with maximum temperatures reaching around 31°C (88°F) and an average of 28°C (83°F). The nights remain comfortably warm, with a minimum temperature of approximately 25°C (77°F). This month also sees substantial precipitation, totaling 144 mm (5.7 in) over about 15 rainy days, contributing to the island's lush landscapes. With a humidity level of 69%, visitors can expect a humid but beautifully vibrant atmosphere, making April a unique experience in this tropical paradise.

April Temperature in Ko Samui

As April unfolds in Ko Samui, Thailand, temperatures reach a delightful crescendo, making it one of the warmest months of the year. With a minimum temperature of 25°C (77°F) and an inviting average of 28°C (83°F), the island offers a perfect escape for those seeking sun-soaked relaxation. The maximum temperature soars to a toasty 31°C (88°F), inviting visitors to embrace the clear skies and indulge in the vibrant beach scene. This steady rise from the cooler months of January through March signals the arrival of summer's warmth, suggesting that this month is ideal for exploring the island's stunning beaches or lounging under the sun. With temperatures consistently climbing, April is a wonderful time to experience the tropical allure of Ko Samui.

April Weather in Ko Samui: Daily Temperature Highs, Lows, and Averages

The chart illustrates April temperature patterns in Ko Samui, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Ko Samui, April typically has an average temperature of {2}°C ({3}°F), with highs reaching up to {4}°C ({5}°F) and lows dropping to around {6}°C ({7}°F).
JanFebMarAprMayJunJulAugSepOctNovDec808182838383838282818180
Data source: Temperature data for Ko Samui 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.

April Precipitation in Ko Samui

April marks a significant shift in Ko Samui's weather, featuring a notable increase in precipitation. With 144 mm (5.7 inches) of rainfall spread across 15 days, this month mirrors January’s wetness, highlighting the onset of the island's rainy season. The sky often darkens with clouds, bringing refreshing showers that nourish the vibrant landscape. As the month progresses, the frequency of rain sets the stage for the wetter months ahead, leading into May and June, where rainfall averages remain high with 126 mm (5.0 inches) and 96 mm (3.8 inches), respectively. This trend underscores Ko Samui's tropical climate, where brief but heavy downpours are pivotal for both the lush greenery and the island's charm.

April Precipitation Trends in Ko Samui

The chart displays monthly precipitation patterns in Ko Samui, with values for each month alongside April’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how April’s conditions compare to those of other months. In Ko Samui, April typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec1443938144126967980151241336207
Data source: Precipitation data for April generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

April Humidity in Ko Samui

In April, Ko Samui experiences a moderate humidity level of 69%, which is a slight increase from February and March, both at 68%. This rise marks the beginning of a trend towards more humid conditions as the region braces for the approaching monsoon season. As May rolls in, humidity spikes to 77%, and from June onwards, the island envelops itself in significantly higher humidity levels, peaking in August at an overwhelming 88%. Overall, April serves as a transitional month, where visitors can still enjoy relatively comfortable moisture before the sultry summer takes full effect.

April Average Humidity in Ko Samui

This chart illustrates the average monthly humidity levels in Ko Samui, with April’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In April, average humidity in Ko Samui is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec72%68%68%69%77%86%86%88%87%86%87%84%
Data source: Humidity data for April generated using information from the Copernicus Climate Change Service.

April UV Index in Ko Samui

In April, the UV Index in Ko Samui, Thailand, reaches a striking level of 15, categorized as extreme. This means that just 10 minutes of unprotected exposure can lead to sunburn, emphasizing the importance of sun safety during this peak period. As we move through the year, a noticeable trend emerges: the UV Index remains consistently high, hovering between 14 and 15 from February to April, reinforcing the need for precautions as temperatures rise. Following April, the index begins to slightly taper off in May, yet still remains in the extreme zone. For anyone enjoying the beautiful beaches of Ko Samui, it's crucial to stay vigilant about sun protection. For more detailed insights on UV levels, visit Ko Samui UV Index.

Maximum UV Index Levels in Ko Samui for April

The chart shows the monthly maximum UV Index (UVI) for Ko Samui in April, 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. In April, the maximum UV index in Ko Samui typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec111415151413141414141111
Data source: Ko Samui April 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.

April Sunshine in Ko Samui

April in Ko Samui, Thailand boasts an impressive 318 hours of sunshine, making it a delightful month for sun-seekers. Following a peak in March with 346 hours of radiant light, April maintains a strong brightness, slightly less than its predecessor but still significantly higher than many other months. This trend illustrates the island's transitioning weather as it shifts from the sunniest days of early spring into the more humid summer months. As daylight starts to dip slightly, the beaches are still bathed in sunlight, offering plenty of opportunities for visitors to explore its stunning coastline and vibrant culture. With May just around the corner presenting 331 hours of sunshine, April serves as a perfect prelude to the sunny adventures that await.

Monthly Sunshine Duration in Ko Samui: April Highlighted

The April sunshine duration represents the total number of hours Ko Samui experiences direct sunlight during the month of April, excluding cloudy or obstructed periods. This chart compares the sunshine duration of April with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec252h308h346h318h331h308h314h300h286h287h289h302h
Data source: Ko Samui April Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Ko Samui During April

April in Ko Samui, Thailand, brings an interesting twist to the island's weather patterns, with a sunshine likelihood dropping to 32%—a significant dip compared to the previous months. Following the higher chances of sunny days in February (58%) and March (51%), April's forecast hints at a more variable climate as the island transitions toward the rainy season. This trend of decreasing sunshine continues into May (21%) and June (22%), emphasizing the shift from the dry season, where travelers can expect consistent sunny weather. While April still offers some sun, the waning likelihood suggests it's a good time for visitors to prepare for a mix of sun and potential showers as they enjoy the tropical beauty of the island.

Percentage of Sunny Days in April in Ko Samui

The chart illustrates the percentage of sunny days in Ko Samui throughout the year, with April 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 Ko Samui experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec32%58%52%32%21%22%18%9%11%11%8%39%
Data source: Ko Samui April chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Ko Samui in April

April in Ko Samui, Thailand, offers an enticing 12 hours of daylight, continuing the trend established in March. As the year progresses, daylight duration shifts subtly, with January and February basking in 11 hours of sunshine, while March heralds a slight increase to 12 hours. This pattern remains consistent through April and into the warmer months of May, June, July, August, and September. As the year approaches its end, daylight naturally begins to decrease, returning to 11 hours in October and maintaining this duration until December. This gradual transition reflects the tropical climate's beautiful stability, providing plenty of time to soak up the sun throughout the year.

Average Daylight Hours in Ko Samui for April

The chart illustrates the variation in daylight duration in Ko Samui throughout the year, with April highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec11h 37m11h 48m12h 3m12h 19m12h 32m12h 39m12h 36m12h 24m12h 9m11h 53m11h 40m11h 33m
Data source: Ko Samui daylight hours, calculated by summing the hours between sunrise and sunset for each day.

April Winds in Ko Samui

In April, Ko Samui experiences a noticeable dip in wind speed, averaging only 3.5 m/s (8 mph), the calmest month of the year. This gentle breeze contrasts sharply with the robust currents of the preceding months, where wind speeds hovered around 4.6 to 5.2 m/s. As summer approaches, the island begins to feel the subtle shift towards higher wind speeds again in May, rising to 4.0 m/s (9 mph). Travelers can expect a more tranquil atmosphere in April, perfect for sun-soaked beach days and leisurely strolls, as the prevailing winds retreat, creating a serene ambiance ideal for relaxation and enjoyment of the tropical paradise.

Average April Wind Speed in Ko Samui

The chart displays monthly wind speed patterns in Ko Samui, with values for each month shown alongside April's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how April's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec5.25.04.63.5 m/s4.04.85.44.74.54.75.05.4
Data source: Ko Samui April wind data, generated using information from the Copernicus Climate Change Service.

How April Weather in Ko Samui Compares to Other Months

Weather in Ko Samui varies notably across the year, with each month offering distinct climate conditions. This page compares April’s weather to other months in Ko Samui, focusing on differences in temperature, rainfall, humidity, and UV levels.

April and January weather in Ko Samui exhibit some notable similarities and differences. Both months have comparable temperature ranges, with April featuring slightly warmer conditions: a minimum of 25°C (77°F) and an average of 28°C (83°F), opposed to January's minimum of 24°C (76°F) and an average of 27°C (80°F). Precipitation levels are virtually identical in both months, with each registering 144 mm (5.7 in), but April experiences rainfall on 15 days, slightly more than January's 13 days. Additionally, April has a humidity level of 69%, which is marginally lower than January's 72%. For more details on January weather, visit Ko Samui weather in January.

April and February showcase notable differences in weather patterns. In April, the temperatures are slightly warmer, with a minimum of 25°C (77°F), an average of 28°C (83°F), and a maximum of 31°C (88°F). This month also experiences significantly higher precipitation, accumulating 144 mm (5.7 in) over about 15 days, resulting in a humid atmosphere at 69%. In contrast, February offers milder conditions, with temperatures ranging from a minimum of 25°C (77°F) to a maximum of 28°C (83°F), and a total precipitation of just 39 mm (1.5 in) over 8 days, keeping humidity levels around 68%. For more details on February's weather, visit Ko Samui weather in February.

In comparing the weather of April and March, both months experience warm temperatures, with March having a slight edge in maximum temperatures at 30°C (86°F) compared to April's 31°C (88°F). However, April sees increased precipitation, with 144 mm (5.7 in) over 15 days, while March only receives 38 mm (1.5 in) over 7 days. Humidity levels are quite similar, with March at 68% and April slightly higher at 69%. For more details on the weather trends, you can visit Ko Samui weather in March.

April and May show a transition in weather patterns, with both months experiencing similar average temperatures around 28°C (82°F), but May tends to be slightly warmer, reaching a maximum of 32°C (89°F) compared to April's 31°C (88°F). While April sees more rainfall, totaling 144 mm (5.7 in) over 15 days, May has a lower precipitation of 126 mm (5.0 in) despite having more rainy days, totaling 22. Additionally, May brings about increased humidity, averaging 77% compared to April's 69%. For more detailed insights on weather patterns in May, check out Ko Samui weather in May.

April's weather features slightly warmer temperatures, with an average of 28°C (83°F) and a maximum of 31°C (88°F). However, it also brings significant rainfall, with 144 mm (5.7 in) over 15 days, and a humidity level of 69%. In contrast, June sees similar average temperatures but experiences slightly warmer minimum and maximum temperatures, ranging from 26°C (79°F) to 32°C (89°F). Precipitation in June is lower at 96 mm (3.8 in) but occurs over more days, totaling 18. Additionally, humidity rises to 86% in June, making it feel more muggy. For a detailed look at the weather, check out Ko Samui weather in June.

In comparing the weather of April and July, both months exhibit similar average temperatures, with April recording a minimum of 25°C (77°F) and July a slightly higher minimum of 26°C (80°F). However, April features significantly higher precipitation, with 144 mm (5.7 in) falling over 15 days, compared to July's 79 mm (3.1 in) spread over 17 days. Interestingly, July sees a higher humidity level at 86% compared to April's 69%, making the summer month feel more oppressive despite the slightly lower rainfall. For further details about July weather, you can visit Ko Samui weather in July.

April and August present distinct weather characteristics, despite having similar average temperatures. In April, the temperatures range from a minimum of 25°C (77°F) to a maximum of 31°C (88°F), with an average of 28°C (83°F). The month sees a higher precipitation level of 144 mm (5.7 in) over 15 days, resulting in a humidity level of 69%. In contrast, August maintains slightly warmer minimum temperatures of 26°C (79°F) and a similar maximum of 31°C (89°F), but experiences significantly less rainfall at 80 mm (3.1 in) over 18 days, accompanied by higher humidity at 88%. This makes August feel more humid and damp compared to the relatively drier conditions of April. For a more detailed view on August's weather specifics, check out Ko Samui weather in August.

In comparing the weather of April and September, we find some intriguing similarities and differences. Both months boast an average temperature of around 28°C (82°F), but April tends to be slightly warmer with high temperatures reaching 31°C (88°F) compared to September's maximum of 30°C (86°F). Precipitation is prevalent in both months, with September experiencing slightly more rain at 151 mm (5.9 in) over 21 days, compared to April’s 144 mm (5.7 in) across 15 days. Additionally, September exhibits higher humidity levels at 87%, which is notable compared to April’s 69%. For more detailed insights on September weather, you can visit Ko Samui weather in September.

In comparing the weather of April and October, both months exhibit warm temperatures, with April slightly edging out October in terms of daily averages, boasting a maximum temperature of 31°C (88°F) compared to October's 30°C (85°F). However, October experiences more considerable precipitation, with 241 mm (9.5 in) spread over 28 days, while April sees less rain at 144 mm (5.7 in) over 15 days. Additionally, October has higher humidity levels, reaching 86% compared to April's 69%, creating a more tropical feel. For a more detailed look at October's weather, you can check this link: Ko Samui weather in October.

April and November share similar temperatures in Ko Samui, with both months experiencing a minimum temperature of 25°C (77°F). However, April generally enjoys slightly warmer averages, peaking at 31°C (88°F), compared to November's maximum of 29°C (85°F). In terms of precipitation, April sees significantly less rain, totaling 144 mm (5.7 in) over 15 days, while November has a much wetter climate, with 336 mm (13.2 in) of rain spread across 24 days. Additionally, humidity levels in November are higher at 87%, compared to April’s 69%. For a detailed overview of November's weather, you can check out Ko Samui weather in November.

April and December present a contrast in weather conditions. April typically enjoys warmer temperatures, with averages reaching 28°C (83°F) and highs of 31°C (88°F), while December sees slightly cooler temperatures, averaging around 27°C (80°F) and peaking at 29°C (84°F). However, December experiences higher precipitation, totaling 207 mm (8.1 in) over 17 days, compared to April's 144 mm (5.7 in) across 15 days. Additionally, the humidity is notably higher in December at 83%, compared to April's 69%. For more detailed information about December weather, you can visit Ko Samui weather in December.

Compare Ko Samui's Climate with Cities Worldwide

Conclusion: What to Expect From April Weather in Ko Samui

April in Ko Samui heralds the arrival of warmer temperatures and increased humidity, distinguishing it from the preceding months. As the island transitions into the heart of the wet season, visitors can expect frequent rain showers paired with sultry heat, creating a vibrant tropical atmosphere. While daytime temperatures soar, making it perfect for beach lovers, the occasional precipitation adds a refreshing touch to the mix. This blend of sun and rain makes April a unique time to experience the island's lush landscapes and vibrant culture. For more insights into the weather patterns throughout the year, visit Ko Samui Climate.