December weather forecast
São Mateus do Maranhão, Brazil

The first month of the summer, December, is also a hot month in São Mateus do Maranhão, Brazil, with an average temperature fluctuating between 33.1°C (91.6°F) and 23°C (73.4°F).

Temperature

The average high-temperature is a hot 33.1°C (91.6°F) in December, hardly different from the 35°C (95°F) recorded in November. During the nights in December, São Mateus do Maranhão experiences a consistent average temperature of 23°C (73.4°F).

Heat index

December's average heat index is appraised at a burning hot 46°C (114.8°F). Mind: Heat cramps along with heat exhaustion are anticipated. Heatstroke can develop with continued physical activity.
Heat index specifics point out values are for conditions of shade and a slight breeze. Exposure to direct sunshine can increase heat index values by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'apparent temperature', combines both the air temperature and the humidity level to give a perceived human temperature. Metabolic differences, pregnancy status, and the level of physical activity are additional factors influencing an individual's weather perception. Should you be directly under the sun, anticipate a possible increase in the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely vital to babies and toddlers. Young individuals are typically more threatened than adults due to their reduced perspiration. Also, the larger skin surface proportionate to their small bodies and the increased heat from their activities magnify their risk.
The human body cools itself through perspiration, as excessive warmth is removed from the body through sweat evaporation. When relative humidity increases, the body's capacity to evaporate heat decreases, leading to a heightened sense of warmth. When heat surpasses the body's release mechanisms, dehydration and overheating risks become pronounced.

Humidity

In December, the average relative humidity is 75%.

Rainfall

In São Mateus do Maranhão, Brazil, in December, it is raining for 23.1 days, with typically 124mm (4.88") of accumulated precipitation. Throughout the year, there are 247.2 rainfall days, and 1281mm (50.43") of precipitation is accumulated.

Daylight

With an average of 12h and 24min of daylight, December has the longest days of the year in São Mateus do Maranhão.
On the first day of the month, sunrise is at 05:36 and sunset at 17:57. On the last day of December, sunrise is at 05:50 and sunset at 18:11 -03.

Sunshine

In São Mateus do Maranhão, the average sunshine in December is 8h.

UV index

The months with the lowest UV index in São Mateus do Maranhão are February through June and December, with an average maximum UV index of 6. A UV Index estimate of 6 to 7 represents a high threat to health from unprotected exposure to Sun's UV rays for the ordinary person.
Note: A maximum UV index of 6 in December translates into the following recommendations:
Avoid overexposure. Fair-skinned individuals can burn in under 20 minutes. Avoid direct Sun exposure and seek shade between 10 a.m. and 4 p.m., when UV radiation is at its peak, but keep in mind that not all shade structures provide complete protection. Limit sun-induced ocular harm with sunglasses that feature UVA and UVB filtration.