December marks a return to the stable weather conditions observed at the start of the year, with low rainfall and high daylight hours. Even as the temperature begins to experience a slight decrease, the town’s typical warm weather remains. December has the significant distinction of minimum rainfall, averaging a paltry 6mm (0.24"), marking the driest period of the year. Even with receding daylight hours, the conditions continue to favor tourism and outdoor engagements.
Temperature
The arrival of December records an average high-temperature of a still hot 32°C (89.6°F), closely related to the 32.6°C (90.7°F) observed in
November. December brings with it a nighttime average temperature of 21.3°C (70.3°F).
Heat index
The heat index in December is estimated at an extremely hot 40°C (104°F). Adopt extra safety steps, risk of heat exhaustion and heat cramps is notable. Sustained activity might cause heatstroke.
Realize that the values for the heat index are set for shaded places and light winds. Exposure to direct sunshine can increase heat index values by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'feels like', is a calculation that merges air temperature and relative humidity to depict the sensation of warmth. The effect is personal, with varied weather perceptions among individuals due to differences in body mass, stature, and physical activity. Consider the sun's direct rays and their impact; they can potentially increase the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are quite important for babies and toddlers. 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.
Perspiration is essential for the human body; it facilitates cooling through the process of sweat evaporation. When there is abundant moisture in the air, the body's cooling through the evaporation process becomes less effective, leading to the sensation of overheating. Excessive heat that's not properly managed leads to increased body temperatures and resultant health issues.
Humidity
The least humid month is December, with an average relative humidity of 70%.
Rainfall
The month with the least rainfall is December, when the rain falls for 1 days and typically collects 6mm (0.24") of precipitation.
Sea temperature
In
Rayong,
Thailand, in December, the average water temperature is 28.3°C (82.9°F).
Note: Water activities in temperatures ranging from 25°C (77°F) to 29°C (84.2°F) are pleasurable, without feeling uncomfortable even during extended periods.
Daylight
December has the shortest days of the year, with an average of 11h and 24min of daylight.
On the first day of the month, sunrise is at 06:21 and sunset at 17:47. On the last day of December, in Rayong, sunrise is at 06:36 and sunset at 18:00 +07.