October weather forecast
Colombo, Sri Lanka

As October sets into Colombo, the declining rainfall trend continues to 237mm (9.33"), with slightly less cloud cover compared to September. Meanwhile, daily temperatures show a small increase, offering warmer conditions. Opportunities for exploring the city increase with daylight hours still around 12, creating extended periods of sunlight. The month's calm wind might not thrill extreme sports enthusiasts but promises serene outdoor activities.

Temperature

Colombo, Sri Lanka, marks the start of October with an average high-temperature of a tropical 30°C (86°F), hinting at a slight fluctuation from September's 29.1°C (84.4°F). During the month of October, Colombo identifies an average nighttime low-temperature of 25°C (77°F), slightly lower than its daytime counterpart.

Heat index

October's heat index is computed to be a sweltering 38°C (100.4°F). Special measures are necessary to avoid heat cramps and heat exhaustion. Persistent activity could result in heatstroke.
It is noted that heat index values are ascertained for locations in the shade and with gentle breezes. If exposed to direct sunlight, the heat index could climb by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature' or 'real feel', is an aggregate value of air's warmth and moisture to show the human-felt temperature. The influence of weather is personal, differing among a variety of individuals based on differences in body mass, stature, and the level of physical activity. It is important to note that direct sunlight can intensify the weather impact, potentially raising the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values remain especially vital for babies and toddlers. Kids are generally in more danger than adults because they perspire less. Their large skin surface area compared to their small bodies and the excessive heat due to their actions raises their risk.
The human body has a built-in cooling mechanism through perspiration; evaporating sweat dissipates the excess heat. When relative humidity is on the rise, it curtails evaporation, thereby reducing the heat elimination from the body and causing the feeling of being excessively hot. Elevated heat gain compared to the body's release capability poses risks of dehydration and potential overheating.

Humidity

In Colombo, the average relative humidity in October is 80%.

Rainfall

In October, the rain falls for 27 days. Throughout October, 237mm (9.33") of precipitation is accumulated. Throughout the year, there are 289.4 rainfall days, and 2262mm (89.06") of precipitation is accumulated.

Sea temperature

In Colombo, the average seawater temperature in October is 28.6°C (83.5°F).
Note: Water temperature from 25°C (77°F) to 29°C (84.2°F) is considered very warm, making water activities enjoyable for prolonged periods without any uncomfortable sensations.

Daylight

The average length of the day in October in Colombo, Sri Lanka, is 11h and 58min.
On the first day of the month, sunrise is at 05:58 and sunset at 18:01. On the last day of October, sunrise is at 05:57 and sunset at 17:50 +0530.

Sunshine

In Colombo, the average sunshine in October is 7.7h.

UV index

May, June, August and October, with an average maximum UV index of 6, are months with the lowest UV index. A UV Index estimate of 6 to 7 represents a high health hazard from exposure to the Sun's UV rays for the average person.
Note: A daily high UV index of 6 in October leads to these guidelines:
Continue precautions and advocate sun safety advice. Deterrence of sunburn is indispensable. The Sun's UV radiation is most potent between 10 a.m. and 4 p.m. Try to limit direct exposure to the Sun during this period. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes. Caution! The reflection of sand and water significantly increases the intensity of the Sun's UV radiation.