September weather forecast
Kollupitiya, Sri Lanka

The first month of the autumn, September, is still a warm month in Kollupitiya, Sri Lanka, with an average temperature ranging between min 24.9°C (76.8°F) and max 29.1°C (84.4°F).

Temperature

Kollupitiya marks the start of September with an average high-temperature of a still moderately hot 29.1°C (84.4°F), hinting at a slight fluctuation from August's 28.9°C (84°F). Kollupitiya marks an average drop to a still warm 24.9°C (76.8°F) during nighttime in September, following the high of the day.

Heat index

September's average heat index is evaluated at a very hot 35°C (95°F). Implement more preventive measures, heat cramps and heat exhaustion are probable. Heatstroke might result from extended activity.
It is essential to grasp that the heat index's numbers are for shade and light wind settings. Direct sunlight can potentially boost the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'real feel', evaluates the perceived heat by adding the effect of moisture in the air. The influence of weather is personal, with varied individuals experiencing it differently due to differences in body mass, stature, and physical exertion levels. Considering the impact of direct sunlight, it's possible for the heat index to surge by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely vital to babies and toddlers. Typically, children face more danger than adults as they usually perspire less. Their larger skin surface relative to their small bodies and increased heat output from their activities enhance their risk.
The human body cools itself through perspiration, as excessive warmth is removed from the body through sweat evaporation. An increase in relative humidity hinders the body's normal cooling function by reducing evaporation, thereby decreasing the rate of body cooling and enhancing the sense of warmth. Accumulating more heat than the body can dissipate leads to an uptick in body temperature, with potential heat stress consequences.

Humidity

In September, the average relative humidity in Kollupitiya is 81%.

Rainfall

In Kollupitiya, in September, during 26.9 rainfall days, 206mm (8.11") of precipitation is typically accumulated. In Kollupitiya, during the entire year, the rain falls for 289.4 days and collects up to 2262mm (89.06") of precipitation.

Daylight

In September, the average length of the day in Kollupitiya, Sri Lanka, is 12h and 10min.
On the first day of the month, sunrise is at 06:03 and sunset at 18:17. On the last day of September, sunrise is at 05:58 and sunset at 18:02 +0530.

Sunshine

The average sunshine in September is 7.4h.

UV index

January through April, July, September, November and December, with an average maximum UV index of 7, are months with the highest UV index. A UV Index estimate of 6 to 7 represents a high threat to health from unprotected exposure to Sun's UV rays for average individuals.
Note: The daily high UV index of 7 during September translates into the following recommendations:
Persist in precautions and follow sun safety policies. Keeping sunburn at bay is imperative. 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. Always opt for UVA and UVB-resistant sunglasses on radiant days.