December weather forecastTrincomalee, Sri Lanka
December
Weather in December
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.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Trincomalee, Sri Lanka
- Average high temperature in December: 29.3°C
The warmest month (with the highest average high temperature) is April (34.9°C).
The months with the lowest average high temperature are January and December (29.3°C).
- Average low temperature in December: 21.4°C
The month with the highest average low temperature is June (24.8°C).
The coldest months (with the lowest average low temperature) are January and February (20°C).
Average pressure in December
Trincomalee, Sri Lanka
- Average pressure in December: 1010.6mbar
The month with the highest atmospheric pressure is January (1012mbar).
The month with the lowest atmospheric pressure is June (1007.5mbar).
Average wind speed in December
Trincomalee, Sri Lanka
- Average wind speed in December: 9.1km/h
The windiest month (with the highest average wind speed) is June (23.8km/h).
The calmest month (with the lowest average wind speed) is April (7.1km/h).
Average humidity in December
Trincomalee, Sri Lanka
- Average humidity in December: 84%
The month with the highest relative humidity is December (84%).
The months with the lowest relative humidity are June, July, August and September (67%).
Average rainfall in December
Trincomalee, Sri Lanka
- Average rainfall in December: 127mm
The wettest month (with the highest rainfall) is October (214mm).
The driest month (with the least rainfall) is June (15mm).
Average rainfall days in December
Trincomalee, Sri Lanka
- Average rainfall days in December: 22.9 days
The month with the highest number of rainy days is November (24.1 days).
The month with the least rainy days is June (7.8 days).
Average sea temperature in December
Trincomalee, Sri Lanka
- Average sea temperature in December: 27.8°C
The best month for swimming (with the highest average sea temperature) is May (30.2°C).
The coldest month (with the lowest average sea temperature) is January (27.1°C).
Average daylight in December /
Average sunshine in December
Trincomalee, Sri Lanka
- Average daylight in December: 11h and 36min
The month with the longest days is June (Average daylight: 12h and 36min).
The month with the shortest days is December (Average daylight: 11h and 36min).
- Average sunshine in December: 4h and 54min
The month with the most sunshine is June (Average sunshine: 11h and 18min).
The month with the least sunshine is December (Average sunshine: 4h and 54min).
Average sunshine days in December
Trincomalee, Sri Lanka
- Average sunshine days in December: 5.9 days
The month with the most sunshine days is July (16 days).
The month with the least sunshine days is November (4.2 days).
Average UV index in December
Trincomalee, Sri Lanka
- Average UV index in December: 6
The months with the highest UV index are February, March, April, May, June, July, August, September and October (UV index 7).
The months with the lowest UV index are January, November and December (UV index 6).
Average cloud cover in December
Trincomalee, Sri Lanka
- Average cloud cover in December: 56
The month with the most cloud cover is December (Cloud cover 56).
The month with the least cloud cover is May (Cloud cover 26).
Average visibility in December
Trincomalee, Sri Lanka
- Average visibility in December: 7km
The months with the highest visibility are May, June, July, August and September (10km).
The months with the lowest visibility are January and December (7km).





