December weather forecast
Santíssimo, Brazil

The first month of the summer, December, is also a moderately hot month in Santíssimo, Brazil, with temperature in the range of an average low of 21.3°C (70.3°F) and an average high of 29.3°C (84.7°F).

Temperature

The transition into December is marked with an average high-temperature of a still warm 29.3°C (84.7°F), showing an insignificant shift from November's 27.2°C (81°F). In Santíssimo, an average temperature of 21.3°C (70.3°F) is noted during December nights.

Heat index

The heat index value for December is calculated to be a fiery hot 36°C (96.8°F). More protective measures are required - heat exhaustion and heat cramps are likely. Heatstroke may follow lengthy activity.
Know that the heat index computations account for shaded terrains and slight winds. The presence of direct sunlight can raise the heat index values by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'apparent temperature', is a single figure representing how weather conditions feel when combining temperature and humidity. An individual's perception of weather can be influenced by a variety of factors including metabolic differences, being pregnant, and their degree of physical exertion. It is important to note that direct sunlight can intensify the weather impact, potentially raising the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values hold great significance to children. Children frequently underestimate the importance of resting and drinking fluids. Thirst is a symptom of advanced dehydration - hence the need to hydrate regularly, especially during protracted physical exercises.
The human body cools itself through perspiration, as excessive warmth is removed from the body through sweat evaporation. In the presence of abundant moisture in the atmosphere, the cooling process through evaporation is hindered, causing the body to feel excessively warm. When body temperature rises due to excess heat gain beyond its removal capability, one might experience heat-related disorders.

Humidity

In Santíssimo, the average relative humidity in December is 82%.

Rainfall

In Santíssimo, during December, the rain falls for 25.7 days and regularly aggregates up to 134mm (5.28") of precipitation. In Santíssimo, during the entire year, the rain falls for 220.6 days and collects up to 991mm (39.02") of precipitation.

Daylight

December has the longest days of the year, with an average of 13h and 30min of daylight.
On the first day of the month, sunrise is at 05:00 and sunset at 18:26. On the last day of December, sunrise is at 05:11 and sunset at 18:42 -03.

Sunshine

In December, the average sunshine is 7.5h.

UV index

With an average maximum UV index of 7, December is the month with the highest UV index. A UV Index reading of 6 to 7 represents a high threat to health from unsafe exposure to UV radiation for the average person.
Note: The maximum UV index of 7 during December leads to these instructions:
Adhere to precautions and respect sun safety doctrines. Avoiding sunburn is vital. The Sun's UV radiation is most potent between the hours of 10 a.m. and 4 p.m. Try to avoid direct sunlight during this time. For optimum UV protection, wear sun-resistant attire complemented with a hat and quality shades.