January weather forecastKo Samui, Thailand

January
Weather in January
January receives 86mm (3.39") of rain, making it one of the driest months in the year for Ko Samui, Thailand. With these weather conditions, tourists find this month perfect for their travel plans. The cool sea breeze adds a layer of comfort to the prevailing weather. January's weather paves the way for the slightly drier February. The UV index is at its lowest.Temperature
In Ko Samui, January records the lowest average temperatures, peaking at 29°C (84.2°F) and reaching a low of 24.2°C (75.6°F).Heat index
The heat index value during January is computed to be a very hot 35°C (95°F). Exercise special caution, heat exhaustion and heat cramps are probable. Prolonged activity may induce heatstroke.From a standpoint of the heat index, values pertain to shaded conditions and mild breezes. Exposure to direct sunshine can increase heat index values by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'apparent temperature', is an aggregate value of air's warmth and moisture to show the human-felt temperature. Factors encompassing physical activity, clothing, and metabolic differences have a role in shaping the individual's impression of temperature. One should be aware that direct sunshine can amplify the perceived temperature, raising the heat index by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values are primarily vital for children. Youngsters typically face more danger than adults since they sweat less. Their larger skin surface compared to their small bodies and heightened heat production from their activities augment their vulnerability.
Evaporating sweat is a key way the human body dispels excessive warmth, all thanks to the process of perspiration. Excessive relative humidity disturbs the body's typical cooling process by reducing evaporation, leading to a decrease in body cooling rate and an increase in the sensation of warmth. Excessive heat gain, when not shed effectively by the body, can result in increasing body temperatures and related hazards.
Humidity
In January, the average relative humidity in Ko Samui is 83%.Rainfall
In Ko Samui, during January, the rain falls for 11 days and regularly aggregates up to 86mm (3.39") of precipitation. In Ko Samui, during the entire year, the rain falls for 160 days and collects up to 1960mm (77.17") of precipitation.Sea temperature
January is the month with the coldest seawater in Ko Samui, with an average sea temperature of 27.8°C (82°F).Note: Surface water temperatures ranging from 25°C (77°F) to 29°C (84.2°F) are considered superb and highly pleasant for water activities over extended periods.
Daylight
In January, the average length of the day is 11h and 38min.On the first day of January, sunrise is at 06:35 and sunset at 18:10. On the last day of the month, sunrise is at 06:41 and sunset at 18:24 +07.
Sunshine
In January, the average sunshine in Ko Samui is 7h.UV index
In January, the average daily maximum UV index in Ko Samui is 11. A UV Index estimate of 11, and higher, represents an extreme threat to health from unsafe exposure to UV radiation for the average person.Note: In January, a daily maximum UV index of 11 leads to the following instructions:
Implement all necessary safeguards, unprotected skin might suffer burns rapidly. Limit direct sun exposure especially between 10 a.m. and 4 p.m., when UV radiation is at its peak. However, keep in mind that shade structures may not provide full sun protection. For excellent sun protection for the eyes, ears, face, and neck, consider a wide-brim hat. Even when it's cloudy, ensure the generous application and frequent reapplication of a sunscreen with at least 30 SPF, particularly post swim or outdoor activity. Be careful! The Sun's UV radiation is accentuated by reflecting off sand and water.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in January
Ko Samui, Thailand
- Average high temperature in January: 29°C
The warmest month (with the highest average high temperature) is April (32.6°C).
The month with the lowest average high temperature is January (29°C).
- Average low temperature in January: 24.2°C
The month with the highest average low temperature is April (26.1°C).
The coldest month (with the lowest average low temperature) is December (23.9°C).
Average humidity in January
Ko Samui, Thailand
- Average humidity in January: 83%
The months with the highest relative humidity are October and November (85%).
The months with the lowest relative humidity are June, July and August (78%).
Average rainfall in January
Ko Samui, Thailand
- Average rainfall in January: 86.2mm
The wettest month (with the highest rainfall) is November (506.6mm).
The driest month (with the least rainfall) is February (54.4mm).
Average rainfall days in January
Ko Samui, Thailand
- Average rainfall days in January: 11 days
The months with the highest number of rainy days are October and November (20 days).
The month with the least rainy days is March (4 days).
Average sea temperature in January
Ko Samui, Thailand
- Average sea temperature in January: 27.8°C
The best month for swimming (with the highest average sea temperature) is May (30.1°C).
The coldest month (with the lowest average sea temperature) is January (27.8°C).
Average daylight in January /
Average sunshine in January
Ko Samui, Thailand
- Average daylight in January: 11h and 36min
The month with the longest days is June (Average daylight: 12h and 42min).
The month with the shortest days is December (Average daylight: 11h and 36min).
- Average sunshine in January: 7h
The month with the most sunshine is February (Average sunshine: 9h).
The months with the least sunshine are May, June, July, August, September, October, November and December (Average sunshine: 6h).
Average UV index in January
Ko Samui, Thailand
- Average UV index in January: 11
The months with the highest UV index are February, March, April, May, June, July, August, September and October (UV index 12).
The month with the lowest UV index is December (UV index 10).





