December weather forecast
Jaffna, Sri Lanka

In December, rainfall drops to 140mm (5.51"), indicating the retreat of monsoons from Jaffna. In line with this decline, the atmospheric pressure also elevates to 1010.9 mb from the previous month's recorded. Gradual changes in climatic conditions are becoming evident in Jaffna during December. The weather remains partly cloudy, favoring outdoor activities during the day while cooler nights are quite common, paving the way for the city's transition into the dry season once again.

Temperature

At the onset of December, Jaffna records an average high-temperature of a still warm 27.5°C (81.5°F), showing little deviation from the preceding month. The month of December in Jaffna is marked by an average minimum temperature of 26.1°C (79°F), slightly cooler than its daytime counterpart.

Heat index

In December, the average heat index is calculated to be a tropical 31°C (87.8°F). If one sustains activity during exposure, it could lead to a sense of fatigue, with a chance of heat cramps.
Metrics for the heat index primarily focus on shaded spots and light wind conditions. With exposure to direct sunlight, the heat index may be increased by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'real feel', reflects the blend of air temperature and relative humidity to give a temperature impression. Additional elements encompassing metabolic differences, the degree of physical activity, and attire can impact the individual's perception of temperature. One's exposure to direct sunlight has the potential to intensify the heat sensation, increasing the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly meaningful for babies and toddlers. Young ones often underestimate the need for rest and rehydration. Thirst appears late in dehydration - hence, it is important to keep hydrated, particularly during prolonged physical activities.

Humidity

In December, the average relative humidity in Jaffna, Sri Lanka, is 78%.

Rainfall

In December, the rain falls for 20 days. Throughout December, 140mm (5.51") of precipitation is accumulated. In Jaffna, during the entire year, the rain falls for 148.6 days and collects up to 769mm (30.28") of precipitation.

Sea temperature

In Jaffna, in December, the average water temperature is 27.3°C (81.1°F).
Note: Engaging in swimming, diving, or other water activities is highly enjoyable in temperatures ranging from 25°C (77°F) to 29°C (84.2°F), without any unpleasant sensations for prolonged durations.

Daylight

December has the shortest days of the year, with an average of 11h and 36min of daylight.
On the first day of December in Jaffna, sunrise is at 06:10 and sunset at 17:47. On the last day of the month, sunrise is at 06:25 and sunset at 18:00 +0530.

Sunshine

With an average of 5.5h of sunshine, December has the least sunshine of the year in Jaffna.

UV index

The months with the highest UV index in Jaffna are January through October and December, with an average maximum UV index of 7. A UV Index value of 6 to 7 symbolizes a high threat to health from exposure to the Sun's UV radiation for the ordinary person.
Note: A maximum high daily UV index of 7 during December translates into the following directions:
Take precautions and adopt sun safety practices. Protection against sunburn is obliged. Try to minimize direct Sun exposure between 10 a.m. and 4 p.m., the peak period for UV radiation. Also note that objects like parasols or canopies might not provide complete sun protection. Stay sun-safe with clothing that is both closely woven and worn loosely. Warning! Sand and water reflections boost the intensity of UV exposure.