December weather forecast
Dumai, Indonesia

December, the first month of the winter in Dumai, is still a hot month, with an average temperature ranging between min 23.7°C (74.7°F) and max 30.6°C (87.1°F).

Temperature

Dumai's temperatures tend to hit their minimum during January and December, with an average high-temperature of 30.6°C (87.1°F).

Heat index

The average heat index in December is appraised at a blistering 41°C (105.8°F). Implement enhanced safety actions, heat cramps and heat exhaustion could occur. Sustained activity might result in heatstroke.
Remember that heat index calculations are made for conditions in the shade with light wind. The heat index could experience an increase of 15 Fahrenheit (8 Celsius) degrees due to direct sunlight.
Note: The heat index, also known as 'apparent temperature' or 'feels like', is an amalgamation of air temperature and humidity to express the equivalent perceived temperature. An individual's perception of weather can be affected by a variety of elements including metabolic differences, being pregnant, and their level of physical exertion. Awareness of direct sun exposure is crucial as it has the potential to heighten the weather's effects, pushing up the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly relevant to babies and toddlers. Kids frequently ignore the importance of taking a break and rehydrating. Thirst is a late symptom of dehydration - thus, it is crucial to stay hydrated, especially during long-lasting physical activities.
Through perspiration, the body has a natural mechanism to eliminate excessive heat via sweat evaporation. With an abundance of moisture present in the air, the process of evaporation becomes less effective, and the body fails to cool down as it should, leading to the sensation of overheating. When body temperature rises due to excess heat gain beyond its removal capability, one might experience heat-related disorders.

Humidity

November and December, with an average relative humidity of 83%, are the most humid months.

Rainfall

In Dumai, during December, the rain falls for 24.1 days and regularly aggregates up to 120mm (4.72") of precipitation. In Dumai, Indonesia, during the entire year, the rain falls for 286.4 days and collects up to 1200mm (47.24") of precipitation.

Sea temperature

In Dumai, the average seawater temperature in December is 29.3°C (84.7°F).
Note: Water temperatures between 25°C (77°F) and 29°C (84.2°F) are regarded as highly pleasant, making all water activities enjoyable without any discomfort over long durations.

Daylight

With an average of 12h and 0min of daylight, December has the shortest days of the year.
On the first day of December in Dumai, sunrise is at 06:02 and sunset at 18:04. On the last day of the month, sunrise is at 06:16 and sunset at 18:18 WIB.

Sunshine

December has the least sunshine of the year in Dumai, with an average of 7h of sunshine.

UV index

The months with the lowest UV index in Dumai are October and December, with an average maximum UV index of 6. 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: The UV index of 6 in December translates into these instructions:
Implement precautions and maintain sun safety methods. Avoidance of sunburn is demanded. Avoid direct Sun exposure from 10 a.m. to 4 p.m., a period when UV radiation is most intense, and remember that not all shade structures provide full protection. For excellent sun protection for the eyes, ears, face, and neck, consider a wide-brim hat. Stay aware! UV radiation is magnified when reflecting off sand and water.