Koh Samui weather in January
Monthly temperatures, rain, humidity, what to wear and what to pack — 2024–2025 historical average
Koh Samui January weather at a glance
In January, Koh Samui averages 23.7°C, with typical highs of 25.7°C and lows of 21.8°C. The historical average is 18 wet days and 77% humidity.
Koh Samui January temperature & humidity
Koh Samui January rain & wet days
Pack a light rain jacket, waterproof pouch and quick-dry shoes. Keep an indoor stop available between outdoor activities.
What to wear in Koh Samui in January
Choose breathable summer clothes and pack sun protection. Rain is frequent at roughly 18 days in the month; pack a rain jacket and water-resistant shoes.
- DaytimeBreathable short sleeves, hat and sunscreen · average high 25.7°C
- Morning & eveningLight layer for air-conditioned rooms · average low 21.8°C
- FootwearComfortable walking shoes; quick-dry footwear for rainy days.
Packing essentials
Coupang affiliate links · We earn a commission on purchases. Products are sold on the Korean Coupang store.
Koh Samui January sunrise & sunset times
2026 January · Local time (Asia/Bangkok)
| Date | Sunrise | Sunset | Daylight |
|---|---|---|---|
| 2026-01-01 | 06:36 | 18:11 | 11h 35m |
| 2026-01-15 | 06:40 | 18:18 | 11h 38m |
| 2026-01-31 | 06:42 | 18:25 | 11h 43m |
For sunset photos, arrive before the listed sunset time. Clouds, mountains and buildings can change when the sun becomes visible or disappears.
Calculated for the city coordinates with daylight saving applied. SunCalc · tz-lookup
Koh Samui travel updates
Watch live CCTV
- Koh Samui / live channelThe Real Samui · Camera directory
Check the camera timestamp at the source.
Today’s weather and forecast
Check temperature, rain and wind in Windy.
Forecast · Windy. Monthly averages are in the Temperature section.
Koh Samui news search
Search for recent news and check publication dates before you travel.
Koh Samui city map
This map shows the city area, not a specific meeting point.
Koh Samui rainy season & dry season
Is January wet or dry?
Thailand’s southwest monsoon generally brings rain from mid-May to mid-October. The southern east coast also receives northeast-monsoon rain, so Koh Samui and Phuket do not share one wet/dry-season calendar. The 2024–2025 average for January is 18 wet days.
2024–2025 wet-day averages, not long-term season boundaries. Wet days do not mean all-day rain.
Packing for rainy and dry periods
For rainy periods, bring a light rain jacket, a waterproof pouch and quick-dry clothes. In drier months, pack sunscreen and a hat, plus a compact umbrella for showers. For beach trips, check the boat operator’s weather and cancellation notices.
Season guide: Thailand Government
Koh Samui travel essentials
Popular MyRealTrip products · city search, sorted by sales · Product names are in Korean.
- Travel SIM card
[공항유심] 태국유심 TRUE/DTAC 4일,7일,10일 무제한 (인천공항 수령)Book now ↗ - Travel SIM card
[태국유심] 데이터 무제한 방콕 여행 AIS 유심칩 도시락유심 공항수령Book now ↗ - Travel eSIM
태국 이심 eSIM 방콕 푸켓 True 매일 500MB 무제한 1일 유심사 알림톡Book now ↗ - Travel eSIM
[20%할인] 태국 로컬 TRUEMOVE 5G/4G 무제한 데이터 eSIMBook now ↗ - Airport transfer
태국 방콕 5G 심카드(방콕 공항 픽업)Book now ↗
Explore with Klook
Klook.comAffiliate widget · We may earn a commission on bookings.
Koh Samui hotel search · Trip.com
Search hotels by destination, dates and number of guests. The Trip.com widget is in Korean.
Affiliate widget · A qualifying booking may earn us a commission. Trip.com may use cookies in this search widget.
Best months to visit Koh Samui
Bar height shows our simple weather-comfort score, not a safety rating; colour shows temperature.
January weather by year
Daily weather in 2025
Daily high and low temperatures; blue labels show precipitation
Frequently asked questions
What is Koh Samui weather like in January?
In January, Koh Samui averages 23.7°C, with typical highs of 25.7°C and lows of 21.8°C. The historical average is 18 wet days and 77% humidity. Our weather-comfort rating for this month is challenging.
Does it rain a lot in Koh Samui in January?
There are about 18 wet days in January. Pack a rain jacket and water-resistant shoes.
What should I wear in Koh Samui in January?
Choose breathable summer clothes and pack sun protection. Rain is frequent at roughly 18 days in the month; pack a rain jacket and water-resistant shoes.
What are the best months to visit Koh Samui?
Recent weather data rates March among the more comfortable months.
Where can I check Koh Samui weather in January in real time?
Check local webcams for the view right now and a local weather service for today’s forecast. Monthly temperatures here are historical averages.
Is January rainy or dry season in Koh Samui?
Thailand’s southwest monsoon generally brings rain from mid-May to mid-October. The southern east coast also receives northeast-monsoon rain, so Koh Samui and Phuket do not share one wet/dry-season calendar. The 2024–2025 average for January is 18 wet days.
Which months have fewer rainy days in Koh Samui?
In our 2024–2025 data, March, April, February have the fewest wet days. These are recent observations, not long-term climate normals. Compare temperatures and your planned activities as well.
What time are sunrise and sunset in Koh Samui in January?
On 2026-01-15, calculated sunrise is 06:40 and sunset is 18:18 in local time (Asia/Bangkok). Times vary by date and terrain.
Koh Samui weather by month
More Southeast Asia destinations in January
Open-Meteo (CC BY 4.0) · 2024–2025 historical data, aggregated and rounded by this site. Not a forecast or long-term climate normal. Calculation method and limitations