Best Time to Visit
Best Time to Visit Koh Samui
🇹🇭 Koh Samui, Thailand · Asia
Based on 30-year climate data (1991-2020) from Open-Meteo
Recommended Travel Months
Jan
25°
23°
Great
Feb
25°
23°
Great
Mar
26°
24°
Great
Apr
27°
24°
Great
May
27°
24°
Good
Jun
27°
24°
Good
Jul
27°
24°
Good
Aug
27°
24°
Good
Sep
26°
23°
Good
Oct
25°
23°
Good
Nov
25°
23°
Good
Dec
25°
23°
Good
Month-by-Month Weather in Koh Samui
| Month | High | Low | Rain Days | Sunshine | Humidity | UV | Rating | Details |
|---|---|---|---|---|---|---|---|---|
| JanuaryRecommended | 25°C | 23°C | 11 | 10h | 82% | 3 | Great | View |
| FebruaryRecommended | 25°C | 23°C | 6 | 11h | 82% | 3 | Great | View |
| MarchRecommended | 26°C | 24°C | 10 | 11h | 82% | 6 | Great | View |
| AprilRecommended | 27°C | 24°C | 12 | 11h | 82% | 6 | Great | View |
| May | 27°C | 24°C | 22 | 10h | 82% | 8 | Good | View |
| June | 27°C | 24°C | 19 | 10h | 82% | 8 | Good | View |
| July | 27°C | 24°C | 18 | 9h | 82% | 8 | Good | View |
| August | 27°C | 24°C | 18 | 9h | 82% | 8 | Good | View |
| September | 26°C | 23°C | 22 | 9h | 82% | 6 | Good | View |
| October | 25°C | 23°C | 26 | 9h | 82% | 6 | Good | View |
| November | 25°C | 23°C | 22 | 9h | 82% | 3 | Good | View |
| December | 25°C | 23°C | 14 | 10h | 82% | 3 | Good | View |
Data source: Open-Meteo ERA5 reanalysis archive, 30-year historical normals (1991-2020). Temperatures in Celsius. Sunshine hours are daily averages.
Seasonal Guide to Koh Samui
Spring (March to May)
Avg: 27°C high, 24°C low
Spring in Koh Samui brings gradually warm temperatures. Daytime highs reach around 27°C (81°F) while nights cool to 24°C (75°F). This is one of the wetter periods, so waterproof gear is recommended.
Summer (June to August)
Avg: 27°C high, 24°C low
Summer is the warmest season in Koh Samui, with temperatures reaching 27°C (81°F). Comfortable warmth makes this a popular time for tourists, though accommodation prices tend to peak. Long daylight hours and abundant sunshine provide plenty of time to explore.
Fall (September to November)
Avg: 25°C high, 23°C low
Fall in Koh Samui is one of the best times to visit. Temperatures settle around 25°C (77°F) during the day and 23°C (73°F) at night. Rainfall picks up during this period, so waterproof clothing is advisable.
Winter (December to February)
Avg: 25°C high, 23°C low
Winter in Koh Samui brings the cooler period, though temperatures remain warm by most standards. This can actually be one of the most comfortable times to visit if you prefer less intense heat.
When to Avoid Koh Samui
The least favorable time to visit Koh Samui is May and June. During this period, you can expect heavy rainfall, high humidity.
May
Challenges: heavy rainfall, high humidity
June
Challenges: heavy rainfall, high humidity
July
Challenges: heavy rainfall, high humidity
Note: visiting during off-peak months often means lower prices, fewer crowds, and a more authentic experience. Consider your priorities when planning your trip.
What to Pack for Koh Samui
Packing recommendations for visiting Koh Samui during the best travel months (February, January, March), when temperatures range from 23°C to 25°C:
- +Light layers for warm days and cooler evenings
- +Comfortable walking shoes
- +A compact umbrella or light rain jacket
- +Sunscreen and sunglasses
- +Reusable water bottle
- +Universal power adapter
Koh Samui Year-Round Climate Overview
Koh Samui has a tropical climate (Koppen classification: Am). The warmest month is August with highs of 27°C, while the coldest month is December at just 25°C. Annual rainfall averages 1530mm across approximately 200 rain days.
| Metric | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| High °C | 25 | 25 | 26 | 27 | 27 | 27 | 27 | 27 | 26 | 25 | 25 | 25 |
| Low °C | 23 | 23 | 24 | 24 | 24 | 24 | 24 | 24 | 23 | 23 | 23 | 23 |
| Rain Days | 11 | 6 | 10 | 12 | 22 | 19 | 18 | 18 | 22 | 26 | 22 | 14 |
| Rain mm | 81 | 36 | 89 | 96 | 115 | 87 | 82 | 91 | 140 | 282 | 284 | 147 |
| Sun h/day | 10 | 11 | 11 | 11 | 10 | 10 | 9 | 9 | 9 | 9 | 9 | 10 |
| Humidity % | 82 | 82 | 82 | 82 | 82 | 82 | 82 | 82 | 82 | 82 | 82 | 82 |
| UV Index | 3 | 3 | 6 | 6 | 8 | 8 | 8 | 8 | 6 | 6 | 3 | 3 |
Compare Nearby Destinations
Considering alternatives to Koh Samui? Compare the best travel months for nearby cities:
Frequently Asked Questions
What is the best month to visit Koh Samui?+
The best time to visit Koh Samui is February, January, March. During these months, temperatures average 25°C (77°F) with 11 hours of daily sunshine and only 9 rain days per month. These conditions offer the most comfortable weather for sightseeing and outdoor activities.
What is the worst time to visit Koh Samui?+
The least ideal time to visit Koh Samui is May and June. During this period, you can expect heavy rainfall, high humidity. While Koh Samui can still be visited during this time (often with fewer crowds and lower prices), the weather may limit outdoor activities.
Is Koh Samui good to visit in summer?+
Summer in Koh Samui (June to August) brings temperatures of 27°C (81°F) highs and 24°C (75°F) lows, with about 9 hours of sunshine and 18 rain days per month. This is generally a good time to visit.
What is the rainy season in Koh Samui?+
The rainy season in Koh Samui runs from May to November, when average rain days increase to 23 days per month. Total monthly precipitation during this period averages 205mm.
What should I pack for Koh Samui?+
When visiting Koh Samui during the best travel months (February, January, March), pack light layers for warm days and cooler evenings, comfortable walking shoes, and a light jacket. A waterproof jacket and umbrella are essential. Sunscreen and sunglasses are recommended.
Is February a good time to visit Koh Samui?+
Yes, February is one of the best months to visit Koh Samui. Expect average highs of 25°C (77°F), 11 hours of daily sunshine, and only 6 rain days. The weather is ideal for exploring the city, visiting outdoor attractions, and enjoying local activities.
Detailed Monthly Weather for Koh Samui
For a complete day-by-day weather breakdown including packing lists, activities, and local events, explore each month individually:
January
February
March
April
May
June
July
August
September
October
November
December
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