The hottest month in Sri Lanka is June when the average maximum temperature is 33°, average temperature is 30° and average minimum temperature is 27°.
The coolest month in Sri Lanka is January when the average maximum temperature is 30°, average temperature is 26° and average minimum temperature is 23°.
The longest days in Sri Lanka are in June, with an average of 12.5 hours of daylight per day. December has the shortest days with an average of 11.7 hours of daylight per day.
The sunniest days in Sri Lanka are in February which has the most hours of sunshine per day with an average of 9.1 hours of sunshine per day, making it a sunny month with few clouds. June has the least sunshine with an average of 8.2 hours of sunshine per day, making it a sunny month with few clouds.
The ultraviolet index is the highest in March when it reaches 15 and lowest in December when it reaches 11.2.
An ultraviolet index reading above 11 indicates an extreme risk of harm from unprotected sun exposure. Unprotected skin risks burning in less than 10 minutes. Take all precautions because unprotected skin and eyes can burn in minutes. Tanning will be safest before 10am and after 4pm but only with a good application of sun screen. For those with sensitive skin stay in the shade and wear protective clothing, a wide-brimmed hat, and UV-blocking sunglasses. Generously apply broad spectrum SPF 30+ sunscreen every 2 hours, even on cloudy days. Watch out for relections from water that may increase ultraviolet exposure.
The warmest sea water temperatures in Sri Lanka are found in April when they peak at 30° and lowest in January when they dip to 27°.
The sea is excellent for swimming all year round as the water temperature is very warm and ideal for relaxing and swimming for the whole day.
The wettest month in Sri Lanka is December with 8.8cm of rain and November has the most days of rain with 17.1 days with some rain, a wet time to visit the beach.
The driest month in Sri Lanka is April with 0.2cm of rain and February has the fewest days of rain with 5 days with some rain, a very dry time to visit the beach.
The most humid month in Sri Lanka is April with a dew point (an indicator of humidity) of 25° which is very uncomfortable and fairly oppressive unless you are on a beach. At night you would most likely require airconditioning.
The least humid month in Sri Lanka is January with a dew point of 23° which is very humid and quite uncomfortable for most unless you are on a beach. At night you would most likely require a fan.
The most windy month in Sri Lanka is July when the average maximum windspeed is 25kmh and the average wind speed is 16kmh.
The least windy month in Sri Lanka is April when the average maximum windspeed is 14kmh and the average wind speed is 7kmh.
