December weather forecast
Tulum, Mexico

Rounding up the year, December weather in Tulum comes with a further decline in temperatures and rainfall, laying the groundwork for the upcoming dry season. Daylight decreases to 10.9 hours, the lowest for the year, and average wind speed picks up slightly to 11.4km/h (7.1mph). The combination of reduced rainfall and cooler average temperatures make it particularly pleasant for exploring Tulum's varied natural and architectural wonders. As Christmas approaches, the town glows with warmth and merriment, creating a festive atmosphere that thoroughly complements the overall weather conditions.

Temperature

The dawn of December sees an average high-temperature of a still warm 27.6°C (81.7°F), subtly contrasting with November's 28.5°C (83.3°F). Throughout December, the average low-temperature dips to an agreeable 22.2°C (72°F).

Heat index

In December, the heat index is appraised at a tropical 31°C (87.8°F). If one endures exposure and continues to be active, it might result in tiredness and heat cramps.
In reference to the heat index, it's for places in shade and with a slight wind. The heat index values could be amplified by up to 15 Fahrenheit (8 Celsius) degrees in direct sunlight.
Note: The heat index, also known as 'felt air temperature' or 'apparent temperature', binds temperature metrics with humidity values to give a sense of the actual warmth. Factors such as metabolic variation, pregnancy, and physical activity play a role in one's impression of weather. Do note, being directly under sun rays can amplify the heat you feel, potentially raising the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values hold great significance to children. In general, younger individuals are at greater risk than adults because they tend to sweat less. Also, having a larger skin surface to body size ratio and greater heat production due to their active behavior contribute to this danger.

Humidity

In Tulum, the average relative humidity in December is 78%.

Rainfall

In Tulum, during December, the rain falls for 18.5 days and regularly aggregates up to 47mm (1.85") of precipitation. In Tulum, during the entire year, the rain falls for 210.8 days and collects up to 810mm (31.89") of precipitation.

Sea temperature

In Tulum, in December, the average water temperature is 27°C (80.6°F).
Note: Water temperature from 25°C (77°F) to 29°C (84.2°F) is considered very warm, making water activities enjoyable for prolonged periods without any uncomfortable sensations.

Daylight

With an average of 10h and 54min of daylight, December has the shortest days of the year.
On the first day of the month, sunrise is at 7:09 am and sunset at 6:08 pm. On the last day of December, sunrise is at 7:25 am and sunset at 6:21 pm EST.

Sunshine

In December, the average sunshine is 8.4h.

UV index

The months with the lowest UV index are January, February, October through 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 radiation for the ordinary person.
Note: The average daily UV index of 6 in December transforms into the following instructions:
Apply measures and align with sun safety principles. Safeguarding against skin and eye injury is pivotal. Avoid direct Sun exposure and seek shade from 10 a.m. to 4 p.m., the period of highest UV radiation. Remember, however, that not all shade structures offer full protection. On days when the sun blazes, arm yourself with sunglasses that block UVA and UVB radiation. Warning! The Sun's UV rays intensify with reflections from sand and water.