December weather forecast
Nonagama, Sri Lanka

The first month of the winter, December, is also a moderately hot month in Nonagama, Sri Lanka, with an average temperature fluctuating between 29°C (84.2°F) and 24.5°C (76.1°F).

Temperature

December is the coldest month, with the temperature often reaching an average high of 29°C (84.2°F) and an average low of 24.5°C (76.1°F).

Heat index

For December, the heat index is computed to be a sweltering 35°C (95°F). Implement additional cautionary measures, heat cramps and heat exhaustion could occur. Prolonged activity might induce heatstroke.
The heat index's values are generally associated with conditions in shade and light breezes. Exposure to unobstructed sunshine could lead to an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'apparent temperature', is a fusion of air temperature and moisture levels to demonstrate the sensation of heat. Additional factors encompassing metabolic differences, the level of physical activity, and clothing 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 of high significance for children. Children are often less aware of the need to rest and re-hydrate. Thirst is a late sign of dehydration - it's vital to remain hydrated, particularly during prolonged physical activities.
The body's inherent cooling system operates through perspiration, wherein evaporating sweat offsets excessive heat. An increase in relative humidity retards evaporation, subsequently reducing the body's heat removal rate and leading to a sensation of being overly warm. Excessive heat that's not properly managed leads to increased body temperatures and resultant health issues.

Humidity

The months with the highest humidity are November and December, with an average relative humidity of 79%.

Rainfall

In December, the rain falls for 20.1 days. Throughout December, 131mm (5.16") of precipitation is accumulated. In Nonagama, during the entire year, the rain falls for 192.9 days and collects up to 942mm (37.09") of precipitation.

Daylight

With an average of 11h and 48min of daylight, December has the shortest days of the year.
On the first day of the month, sunrise is at 06:01 and sunset at 17:49. On the last day of December, sunrise is at 06:15 and sunset at 18:02 +0530.

Sunshine

With an average of 6.6h of sunshine, December has the least sunshine of the year.

UV index

January through September, November and December, with an average maximum UV index of 7, are months with the highest UV index. A UV Index estimate of 6 to 7 represents a high health risk from exposure to the Sun's UV radiation for the average person.
Note: A typical high UV index of 7 in December suggests the following recommendations:
Inhibit overexposure. Warding off sun damage is of utmost importance. It's important to stay in the shade and limit exposure to the sun from 10 a.m. to 4 p.m., when UV radiation is most intense, although remember that shade structures may not provide full sun protection. Boost your sun resistance with garments that are densely woven yet spacious.