December weather forecast
Gampaha, Sri Lanka

As the year ends in Gampaha, the weather takes on a decidedly drier tone. Rainfall decreases further to 139mm (5.47"), indicating the arrival of the dry spell. Daylight hours marginally decrease while winds pick up pace once more, with maximum wind speed increasing up to 15km/h (9.3mph). The rise in wind speed coupled with receding rainfall concludes the year on a fresh, invigorating note. Despite the changing conditions, Gampaha in December continues to attract tourists with its pleasant weather and scenic beauty.

Temperature

December's arrival in Gampaha, Sri Lanka, registers an average high-temperature of a warm 29.9°C (85.8°F), closely aligning with the temperature of the previous month. The low-temperature averages to a still moderately hot 23.7°C (74.7°F) during the nights of December.

Heat index

For December, the heat index is appraised at a fiery hot 37°C (98.6°F). Implement more preventive measures, heat cramps and heat exhaustion are probable. Heatstroke might result from extended activity.
For clarity, heat index numbers account for light winds and areas under shade. Direct sunlight might cause an increase of up to 15 Fahrenheit (8 Celsius) degrees in the heat index.
Note: The heat index, also known as 'feels like' or 'felt air temperature', gives a temperature feeling by integrating air temperature and humidity. Factors such as metabolic variations, being pregnant, and physical activity can impact an individual's weather perception. In direct sunlight, the heat's impact can be heightened, potentially leading to an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly relevant to children. Children often do not understand the need to rest and hydrate. Thirst is a late manifestation of dehydration - therefore, it is essential to stay hydrated, particularly during prolonged physical activities.
Perspiring is a crucial mechanism for the human body, allowing it to release excessive warmth through evaporating sweat. High relative humidity reduces the evaporation rate, resulting in a lower heat removal rate from the body, causing the perception of being overheated. If the body retains more heat than it can expel, the increasing temperature can lead to heat-related conditions.

Humidity

In Gampaha, the average relative humidity in December is 79%.

Rainfall

In Gampaha, during December, the rain falls for 20.3 days and regularly aggregates up to 139mm (5.47") of precipitation. Throughout the year, in Gampaha, there are 265.4 rainfall days, and 1744mm (68.66") of precipitation is accumulated.

Daylight

December has the shortest days of the year, with an average of 11h and 42min of daylight.
On the first day of the month, sunrise is at 06:06 and sunset at 17:51. On the last day of December, in Gampaha, Sri Lanka, sunrise is at 06:21 and sunset at 18:04 +0530.

Sunshine

In Gampaha, the average sunshine in December is 7h.

UV index

January through April, July, September, November and December, with an average maximum UV index of 7, are months with the highest UV index in Gampaha. A UV Index estimate of 6 to 7 represents a high health risk from exposure to the Sun's UV rays for the ordinary person.
Note: In December, an average UV index of 7 transforms into the following instructions:
Persist with precautions and heed sun safety advice. Prevention of sunburn is compulsory. Stay in the shade and limit direct Sun exposure from 10 a.m. to 4 p.m., a time when UV radiation is particularly strong. Remember, however, that shade structures may not provide complete protection. Clothes that are both tight-knit and comfortably loose are prime choices for sun protection.