April weather forecast
Kalutara, Sri Lanka

As we venture into April, there is a visible increasing trend in rainfall. The heat remains on a steady climb, with the highest temperature in April also topping at 31.3°C (88.3°F). This fluctuation leads to increased humidity, making the overall weather feel warmer than it is. Despite the increase in rainfall, April brings about pleasant weather dotted by tropical sunshine and longer daylight hours. The increasing rainfall during April indicates the onset of the monsoon season.

Temperature

The highest point of temperatures falls in March and April, when the average high-temperature ascends to 31.3°C (88.3°F).

Heat index

The heat index in April is evaluated at an extremely hot 41°C (105.8°F). Heightened safety actions are necessary, heat cramps and heat exhaustion are probable. Persistent activity may lead to heatstroke.
Evaluating the heat index requires understanding its values in the shade and with gentle winds. The heat index has the possibility to be enhanced by 15 Fahrenheit (8 Celsius) degrees when there is direct sun exposure.
Note: The heat index, also known as 'felt air temperature' or 'real feel', gives a temperature feeling by integrating air temperature and humidity. A person's impression of weather can be swayed by numerous aspects, among them metabolic variations, pregnancy, and activity levels. When directly under the sun, the weather's impact can intensify, possibly boosting the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly meaningful 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.
To prevent overheating and help regulate its internal temperature, the human body sweat and rely on the evaporation to cool down. During high air temperature and humidity (high heat index), the process of perspiration is hindered, intensifying the sensation of heat. Heat absorption that surpasses the body's shedding capability can lead to overheating and varying levels of dehydration.

Humidity

In Kalutara, the average relative humidity in April is 78%.

Rainfall

In April, the rain falls for 25.8 days. Throughout April, 127mm (5") of precipitation is accumulated. In Kalutara, during the entire year, the rain falls for 273.8 days and collects up to 2059mm (81.06") of precipitation.

Sea temperature

With an average sea temperature of 29.6°C (85.3°F), April is the month with the warmest seawater.
Note: Swimming, diving, and similar water activities in temperatures ranging from 25°C (77°F) to 29°C (84.2°F) are seen as very agreeable and pleasurable for lengthy periods without discomfort.

Daylight

In Kalutara, the average length of the day in April is 12h and 16min.
On the first day of the month, sunrise is at 06:08 and sunset at 18:19. On the last day of April, sunrise is at 05:56 and sunset at 18:17 +0530.

Sunshine

In April, the average sunshine is 9h.

UV index

January through April, July, September through December, with an average maximum UV index of 7, are months with the highest UV index. A UV Index reading of 6 to 7 represents a high health vulnerability from exposure to the Sun's UV radiation for ordinary individuals.
Note: The maximum daily UV index of 7 in April converts into the following recommendations:
Take precautions and utilize sun safety practices. Protection against skin and eye damage is required. Stay in the shade and limit sun exposure from 10 a.m. to 4 p.m., when UV radiation is most potent. Keep in mind that shade structures like parasols or canopies do not offer full protection. During bright days, sunglasses that offer UVA and UVB defense are recommended. Notice! Sand and water reflections contribute to a stronger UV exposure.