September weather forecast
Phuket, Thailand

September in Phuket comes with a climax in monsoon activity. The cold temperatures at night lower to 24.6°C (76.3°F), providing respite from the daily heat. However, the rainfall climbs even higher to 361mm (14.21") resulting in more rain-filled days. The UV index eases slightly, making outdoor activities more favorable during periods without rain. As September transitions to October, a visible reduction in rainfall starts to take shape.

Temperature

Phuket's coldest months, September and October, record an average high-temperature of 31.5°C (88.7°F).

Heat index

September's heat index is estimated at a blisteringly hot 43°C (109.4°F). Take caution: Heat exhaustion and heat cramps are probable. Heatstroke may be imminent with ongoing effort.
Heat index readings emphasize conditions of light breezes and shaded spots. When under direct sunshine, the heat index may be elevated by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature' or 'real feel', evaluates the perceived heat by adding the effect of moisture in the air. The influence of weather is personal, with a diverse population experiencing it differently due to differences in body mass, stature, and degree of activity. Given the impact of direct sunlight, it's noteworthy that the felt temperature can rise by 15 Fahrenheit (8 Celsius) degrees. Heat index values are essentially critical for children. Kids are usually more vulnerable than adults, given their lesser sweating ability. Along with their larger skin surface relative to their small stature and the excess heat due to their activity, their risk is amplified.
One way the human body deals with excessive warmth is by perspiring and allowing sweat to evaporate. An increase in relative humidity disrupts body cooling by slowing the evaporation rate, thereby reducing the rate at which the body cools and amplifying the sense of heat. Elevated heat gain compared to the body's release capability poses risks of dehydration and potential overheating.

Humidity

The months with the highest humidity are September and October, with an average relative humidity of 82%.

Rainfall

The month with the most rainfall is September, when the rain falls for 23 days and typically aggregates up to 361mm (14.21") of precipitation.

Sea temperature

In September, the average sea temperature is 29°C (84.2°F).
Note: For any water activity, temperatures between 25°C (77°F) and 29°C (84.2°F) are deemed excellent and extremely satisfying for enduring periods.

Daylight

In Phuket, the average length of the day in September is 12h and 10min.
On the first day of September in Phuket, sunrise is at 06:18 and sunset at 18:34. On the last day of the month, sunrise is at 06:14 and sunset at 18:18 +07.

Sunshine

In Phuket, Thailand, the average sunshine in September is 4.8h.

UV index

February through October, with an average maximum UV index of 12, are months with the highest UV index. A UV Index estimate of 11, and higher, represents an extreme health hazard from exposure to the Sun's UV rays for average individuals.
Note: A maximum daily UV index of 12 during September morphs into the following directions:
Take every vital safeguard, as unprotected skin and eyes may suffer burns rapidly. Seek shade and minimize exposure to direct Sun in a period between 10 a.m. and 4 p.m. when UV radiation is most intense; keep in mind that shade structures like parasols or canopies do not provide perfect sun protection. Always opt for UVA and UVB-resistant sunglasses on radiant days. Despite the overcast weather, sunscreen with SPF of at least 30 should be applied liberally and reapplied often, particularly after swimming or an outdoor workout. Attention! The combination of sand and water reflections enhances UV ray intensity.