September weather forecast
Rayong, Thailand

September often signals the nearing end of the monsoon period. Whilst high humidity levels persist, the average rainfall in this month reaches a yearly peak of 255mm (10.04"). This is the second highest rainfall in the year after May. Even though rainfall is high, daily temperatures remain consistently high with no significant reductions.

Temperature

The lowest level of Rayong's temperatures is noted during January and September, averaging a high-temperature of 31.9°C (89.4°F).

Heat index

The average heat index in September is estimated at a blazing hot 45°C (113°F). Stay watchful: Heat exhaustion along with heat cramps are likely. Ongoing effort may cause heatstroke.
It is crucial to understand that heat index figures are for shade and gentle wind conditions. A rise of up to 15 Fahrenheit (8 Celsius) degrees in the heat index could result from direct sunlight.
Note: The heat index, also known as 'apparent temperature' or 'feels like', quantifies the warmth felt when relative humidity is considered. Metabolic differences, pregnancy status, and the level of physical activity are additional factors influencing an individual's weather perception. Be aware that direct exposure to sunlight increases heat impact and may raise the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are highly critical for babies and toddlers. Younglings are generally more in peril than adults due to their reduced perspiration. Coupled with a larger skin surface relative to their tiny bodies and greater heat production because of their activity, they become more at risk.
Evaporating sweat, an outcome of perspiration, is key in assisting the human body to moderate its temperature. With a lot of moisture in the air, the evaporation process is not as effective, and the body does not cool down as efficiently, creating a perception of overheating. Rising body temperatures resulting from an imbalance in heat absorption can lead to potential thermal issues.

Humidity

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

Rainfall

The month with the most rainfall is September, when the rain falls for 17 days and typically aggregates up to 255mm (10.04") of precipitation.

Sea temperature

In Rayong, in September, the average water temperature is 29°C (84.2°F).
Note: Water temperatures ranging between 25°C (77°F) and 29°C (84.2°F) are regarded as very warm, making swimming, diving, and similar water activities pleasurable for extended periods.

Daylight

The average length of the day in September in Rayong is 12h and 12min.
On the first day of the month, sunrise is at 06:04 and sunset at 18:26. On the last day of September, in Rayong, sunrise is at 06:04 and sunset at 18:06 +07.