December weather forecast
Trincomalee, Sri Lanka

As the year concludes, December receives less precipitation than November, but relatively higher than January. Marking the tail end of the rainy season, this month witnesses a considerable drop in rainfall compared to November's records. However, sea temperatures and daylight hours hold steady, creating a pleasant atmosphere for activities. Cloud coverage increases significantly, providing shelter from the season’s high UV index. In terms of wind, there is a slight increase from November, adding a refreshing note to the tropical climate.

Temperature

The yearly lowest temperatures in Trincomalee occur in January and December, averaging a high-temperature of 29.3°C (84.7°F).

Heat index

Throughout December, the heat index is estimated at a torrid 37°C (98.6°F). Undertake enhanced precautions, heat exhaustion and heat cramps are possible risks. Continuous activity could trigger heatstroke.
Take note of the fact that heat index values are based on shaded circumstances with light airflows. Facing direct sunlight may hike up the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'feels like', reflects the blend of air temperature and relative humidity to give a temperature impression. 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. Do note, being directly under sun rays can amplify the heat you feel, potentially raising the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are especially vital to children. Youngsters generally face more threats than adults given their lesser ability to sweat. Coupled with their larger skin surface relative to their small bodies and higher heat production due to their activities, they are more endangered.
Humans rely on perspiration as a cooling mechanism, wherein the evaporating sweat counteracts excessive warmth. With high air temperature and humidity (high heat index) conditions, sweat production is restricted, leading to an amplified perception of heat. The body is at risk of dehydration and related complications when it fails to shed excessive heat.

Humidity

The most humid month in Trincomalee is December, with an average relative humidity of 84%.

Rainfall

In Trincomalee, Sri Lanka, during December, the rain falls for 22.9 days and regularly aggregates up to 127mm (5") of precipitation. Throughout the year, there are 196.8 rainfall days, and 943mm (37.13") of precipitation is accumulated.

Sea temperature

In December, the average sea temperature in Trincomalee is 27.8°C (82°F).
Note: Temperatures between 25°C (77°F) and 29°C (84.2°F) are excellent for swimming, diving, and other water activities, providing comfort and enjoyment for extended periods without discomfort.

Daylight

With an average of 11h and 36min of daylight, December has the shortest days of the year in Trincomalee.
On the first day of the month, sunrise is at 06:04 and sunset at 17:44. On the last day of December, in Trincomalee, sunrise is at 06:19 and sunset at 17:57 +0530.

Sunshine

With an average of 4.9h of sunshine, December has the least sunshine of the year in Trincomalee.

UV index

January, November and December, with an average maximum UV index of 6, are months with the lowest UV index in Trincomalee. A UV Index of 6 to 7 symbolizes a high threat to health from exposure to the Sun's UV rays for average individuals.
Note: A maximum high UV index of 6 in December translates into the following recommendations:
Deter overexposure. Protecting against the sun's effects is essential. 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. A wide-brimmed hat provides unparalleled sun protection for sensitive areas like the eyes, ears, and neck. Beware! The reflection of water and sand dramatically increases exposure to the UV rays.