December weather forecast
São Tomé, São Tomé and Príncipe

December brings the yearly climate cycle full circle in São Tomé. It a gradual escalation at the mercury’s scale, the temperature revolves between 22.1°C (71.8°F) and 29.1°C (84.4°F). The weather of December recalls the aura of January, offering a pleasant summation to the climatic journey of the year. The relative humidity is stable, and sunshine hours are constant — traits marking the city's weather staple.

Temperature

December's presence in São Tomé, São Tomé and Príncipe, records an average high-temperature of a still moderately hot 29.1°C (84.4°F), closely mirroring November's climate. Throughout December, an average low-temperature of 22.1°C (71.8°F) is experienced in São Tomé, São Tomé and Príncipe.

Heat index

In December, the heat index is calculated to be a very hot 36°C (96.8°F). Take special precautions - heat exhaustion and heat cramps are expected. Heatstroke may occur with lengthy activity.
Heat index data is primarily for areas with shade and subjected to light winds. Direct sunshine exposure could raise heat index values by as much as 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'felt air temperature', represents the fusion of temperature and moisture in the air to suggest how warm it feels. Elements such as metabolic variations, being pregnant, and physical activity can impact one's weather perception. When exposed to direct sunlight, it's possible for the heat index to increase by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values hold great significance to children. Young individuals usually face more risks than adults due to their lower sweat production. Their large skin surface area relative to their tiny bodies and high heat production from their activities adds to their risk.
Evaporating sweat is a key way the human body dispels excessive warmth, all thanks to the process of perspiration. Augmented relative humidity impedes typical body cooling mechanisms by lowering the evaporation rate, resulting in decreased body cooling and an amplified perception of heat. Heat-related complications, like dehydration, can manifest if the body's heat gain exceeds its dissipation capacity.

Humidity

January, November and December, with an average relative humidity of 85%, are the most humid months in São Tomé.

Rainfall

In São Tomé, São Tomé and Príncipe, in December, during 8 rainfall days, 108mm (4.25") of precipitation is typically accumulated. Throughout the year, in São Tomé, there are 94 rainfall days, and 885mm (34.84") of precipitation is accumulated.

Sea temperature

In São Tomé, in December, the average water temperature is 28°C (82.4°F).
Note: Water temperature ranging between 25°C (77°F) and 29°C (84.2°F) is considered very warm and pleasing for everyone. It allows for enjoyable water activities over extended periods without discomfort.

Daylight

With an average of 12h and 6min of daylight, December has the shortest days of the year.
On the first day of the month, sunrise is at 05:19 and sunset at 17:25. On the last day of December, in São Tomé, sunrise is at 05:33 and sunset at 17:39 GMT.

Sunshine

In São Tomé, the average sunshine in December is 4.6h.

UV index

January through May, August through December, with an average maximum UV index of 12, are months with the highest UV index. A UV Index reading of 11, and higher, represents an ultimate health vulnerability from unprotected exposure to Sun's UV rays for the average person.
Note: The maximum daily UV index, 12 in December, converts into the following recommendations:
Enforce all necessary precautions, unprotected skin might burn swiftly. Remember that the sun's UV radiation is strongest between 10 a.m. and 4 p.m. Make an effort to avoid direct sun exposure during these hours. Outfit yourself in sun-safe attire, like long sleeves, pants, a hat, and UV-blocking sunglasses. Even when it's cloudy, ensure the generous application and frequent reapplication of a sunscreen with at least 30 SPF, particularly post swim or outdoor activity. Be attentive! The UV exposure is heightened with reflections from sand and water.