September weather forecast
Arugam Bay, Sri Lanka

September seems to be the threshold month, marking the beginning of the transition from summer to monsoon in Arugam Bay. As the rains begin to pour in, with September experiencing 81mm (3.19") of precipitation, the weather signals the onset of a wetter period ahead. However, the transition from warmth to a cooler environment remains smooth, ensuring a minimal change in the atmospheric comfort level. Sea temperatures start taking a slight dip while maintaining a warm feel. As September comes to an end, the monsoons set foot in earnest, announcing the start of the rainy season.

Temperature

Upon the onset of September, Arugam Bay witnesses an average high-temperature of a still hot 31.8°C (89.2°F), showing a close resemblance to the prior month. Arugam Bay, during the nights of September, experiences an average temperature drop to a warm 25.7°C (78.3°F).

Heat index

The heat index value for September is computed to be a blisteringly hot 41°C (105.8°F). Exercise extra preventive actions, heat cramps and heat exhaustion are plausible. Continuous activity could result in heatstroke.
One should be cognizant that the heat index values are tailored for shaded spots and mild winds. Direct exposure to sunlight could raise the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'apparent temperature', gives an indication of how one might feel in terms of heat after considering humidity. The impact of weather on an individual can be subjective, affected by the person's activity and heat perception, which can vary due to elements including wind, clothing, and metabolic differences. 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 hold great significance to children. Children frequently do not understand the need for recuperation and hydration. Thirst, being a late manifestation of dehydration, underlines the need to hydrate frequently, especially when engaging in prolonged physical exercises.
The evaporation of sweat is a natural cooling mechanism of the human body, facilitated by perspiration. When the level of relative humidity is elevated, evaporation diminishes, causing more warmth to be retained in the body than in dry air. When heat gain surpasses the level the body can shed, body temperature begins to increase, and consequently, overheating and dehydration can occur, with varying severity.

Humidity

In September, the average relative humidity is 72%.

Rainfall

In September, the rain falls for 22 days. Throughout September, 81mm (3.19") of precipitation is accumulated. In Arugam Bay, during the entire year, the rain falls for 237.8 days and collects up to 1259mm (49.57") of precipitation.

Sea temperature

January, February, July through September and December, with an average sea temperature of 28°C (82.4°F), are months with the coldest seawater in Arugam Bay.
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

The average length of the day in September is 12h and 10min.
On the first day of the month, sunrise is at 05:55 and sunset at 18:09. On the last day of September, in Arugam Bay, sunrise is at 05:50 and sunset at 17:54 +0530.

Sunshine

In Arugam Bay, the average sunshine in September is 10.7h.

UV index

The months with the highest UV index are January through October, with an average maximum UV index of 7. A UV Index value of 6 to 7 symbolizes a high health vulnerability from exposure to the Sun's UV rays for ordinary individuals.
Note: The daily high UV index of 7 during September translates into the following recommendations:
Eschew overexposure. Those with light skin may suffer burns in fewer than 20 minutes. Avoid exposure to the Sun and try to stay in the shade between 10 a.m. and 4 p.m., when UV radiation is most potent, but be aware that parasols or canopies may not offer full protection. Boost your sun resistance with garments that are densely woven yet spacious. Alert! The Sun's UV rays are heightened by the reflection of sand and water.