July weather forecast
Ko Samui, Thailand

July in Ko Samui, Thailand, remains reasonably stable with no drastic changes. The rainfall stays relatively constant around 116mm (4.57"), slightly less than June. Despite the monsoon, an equal amount of sunny and rainy days persists. Temperature follows a similar pattern as June maintaining a balance in the overall climate. This balance carries over into August as well, painting a well-adjusted weather scene.

Temperature

Ko Samui records an average high-temperature of a still hot 32.1°C (89.8°F) in July, closely mirroring the climate of the previous month. In Ko Samui, an average temperature of 25.2°C (77.4°F) is noted during July nights.

Heat index

The heat index in July is computed to be an extremely hot 44°C (111.2°F). Observe: Heat exhaustion and heat cramps are probable. Heatstroke is on the horizon with prolonged exertion.
Be aware that heat index ratings are designed for shaded locations and minor breezes. Direct sunlight exposure may cause a 15 Fahrenheit (8 Celsius) degrees rise in the heat index.
Note: The heat index, also known as 'real feel' or 'apparent temperature', determines the feeling of heat when you account for the relative humidity. Factors such as metabolic variations, being pregnant, and physical activity can impact an individual's weather perception. 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 highly important for children. Children frequently underestimate the importance of resting and drinking fluids. Thirst is a symptom of advanced dehydration - hence the need to hydrate regularly, especially during protracted physical exercises.
Evaporation of sweat is the main factor behind the cooling effect of perspiration in the human body. In situations of high air temperature combined with high humidity (significant heat index), the body's ability to perspire is reduced, heightening the sense of warmth. As body temperatures escalate without effective heat release, one might face dehydration threats.

Humidity

The months with the lowest humidity are June through August, with an average relative humidity of 78%.

Rainfall

In July, the rain falls for 15 days. Throughout July, 116mm (4.57") of precipitation is accumulated. Throughout the year, there are 160 rainfall days, and 1960mm (77.17") of precipitation is accumulated.

Sea temperature

In Ko Samui, in July, the average water temperature is 29.8°C (85.6°F).
Note: For swimming, diving, and enjoying other water activities, the range of 25°C (77°F) to 29°C (84.2°F) in water temperature is considered ideal, offering pleasure for extended periods without discomfort.

Daylight

The average length of the day in July is 12h and 37min.
On the first day of July, sunrise is at 06:03 and sunset at 18:43. On the last day of the month, sunrise is at 06:10 and sunset at 18:42 +07.

Sunshine

May through December, with an average of 6h of sunshine, are months with the least sunshine.

UV index

February through October, with an average maximum UV index of 12, are months with the highest UV index in Ko Samui. A UV Index estimate of 11, and higher, represents an extreme health hazard from unsafe exposure to UV radiation for the ordinary person.
Note: The daily high UV index of 12 during July translates into the following recommendations:
Put into effect every precaution of importance, unprotected skin and eyes may get burns swiftly. Limit your exposure to the sun's UV radiation, which is strongest between 10 a.m. and 4 p.m., and note that parasols or canopies may not provide full sun protection. During bright days, sunglasses that offer UVA and UVB defense are recommended. Despite the cloud cover, sunscreen with an SPF of at least 30 should be generously applied and reapplied, particularly after a swim or an outdoor workout. Beware! Reflecting off water and sand, UV rays are much stronger.