September weather forecast
Petaling Jaya, Malaysia

As Petaling Jaya transitions to September, a slight dip in average monthly temperatures from 23.5°C (74.3°F) to 32.2°C (90°F) is observed. However, this doesn't disturb the uniformity of weather that the city has been experiencing over the past few months. Though the city's skyline often remains cloudy, ample daylight brightens up the surroundings. Typically, September keeps up with the consistency of the monsoon season. October forecasts an increase in rainfall, raising the total to 169mm (6.65").

Temperature

September is marked by an average high-temperature of a still tropical 32.2°C (90°F), almost identical to the preceding month. In September, the average low-temperature records at a warm 23.5°C (74.3°F) during the nights.

Heat index

The heat index for September is estimated at an extremely hot 42°C (107.6°F). Greater preventive actions are needed, heat exhaustion and heat cramps are likely. Persistent activity could provoke 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 'felt air temperature' or 'apparent temperature', offers an insight into how hot it feels when we factor in moisture content. One's perception of temperature can vary depending on physical activity and individual heat sensitivity, influenced by factors like wind, attire, and metabolic variations. In direct sunlight, the heat's impact can be heightened, potentially leading to an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are especially crucial for babies and toddlers. Youngsters often neglect the necessity for rest and hydration. Thirst is a sign of advancing dehydration - thus the importance of maintaining hydration, specifically during long-lasting physical activities.
Evaporating sweat is a key way the human body dispels excessive warmth, all thanks to the process of perspiration. With a high level of moisture in the air, the evaporation process becomes less efficient, preventing the body from cooling down efficiently and resulting in a sensation of overheating. Heat-related disorders may develop if heat gain in the body overshadows its cooling capacity, leading to elevated temperatures.

Humidity

August and September, with an average relative humidity of 73%, are the least humid months.

Rainfall

In September, the rain falls for 26.6 days. Throughout September, 88mm (3.46") of precipitation is accumulated. Throughout the year, there are 309.8 rainfall days, and 1481mm (58.31") of precipitation is accumulated.

Daylight

The average length of the day in September is 12h and 8min.
On the first day of September, sunrise is at 7:08 am and sunset at 7:18 pm. On the last day of the month, sunrise is at 7:00 am and sunset at 7:06 pm +08.

Sunshine

In September, the average sunshine is 8.7h.

UV index

February through October and December, with an average maximum UV index of 7, are months with the highest UV index in Petaling Jaya. A UV Index of 6 to 7 symbolizes a high health vulnerability from exposure to the Sun's UV rays for average individuals.
Note: In September, the maximum UV index of 7 translates into these guidelines:
Skirt overexposure. People with light complexions might get scorched in under 20 minutes. The Sun emits the most powerful UV radiation between 10 a.m. and 4 p.m. Try to avoid direct sunlight during this period. Experience reduced UV exposure by about half when donning a wide-brim hat.