, the first month of the summer in Manaus
, is still a tropical month, with an average temperature fluctuating between 31.3°C (88.3°F) and 23.5°C (74.3°F).
In December, the average high-temperature is practically the same as in November
- a still tropical 31.3°C (88.3°F). In Manaus, the average low-temperature is 23.5°C (74.3°F).
In December, the average heat index is appraised at a blistering 44°C (111.2°F). Beware
: Heat cramps and heat exhaustion are very likely. Heatstroke is imminent with prolonged activity.
Take into consideration that the heat index values are calculated for shade and light wind conditions. Exposure to direct sunshine can increase heat index values by up to 15 Fahrenheit (8 Celsius) degrees.Note
: The heat index, also known as 'felt air temperature', 'feels like', 'apparent temperature', or 'real feel', is a measure of how hot it feels when the actual air humidity is factored in. This effect is individual, with diverse people perceiving weather differently for numerous reasons (metabolic differences, differences in body mass, height, and shape, clothing), and activity. Bear in mind that direct sunshine exposure increases weather impact, and may raise heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly important for children. Children are often less aware of the need to rest and re-hydrate. Thirst is a late sign of dehydration - it is vital to remain hydrated, particularly during prolonged physical activities.
The human body normally cools itself by perspiration. Excessive warmth is eliminated from the body by evaporation of sweat. Under high air temperature and humidity (high heat index) conditions, perspiration is limited, and the perception of heat is increased. If the body can not disperse the excessive heat and body temperature reaches conditions of hyperthermia, above 37.5°C (99.5°F) to 38.3°C (100.9°F), thermal conditions are potentially life-threatening.
In Manaus, the average relative humidity in December is 85%.
In Manaus, during December, the rain falls for 16 days and regularly aggregates up to 220mm (8.66") of precipitation. In Manaus, during the entire year, the rain falls for 160 days and collects up to 2307mm (90.83") of precipitation.
December has the longest days of the year, with an average of 12h and 18min of daylight.
On the first day of the month, sunrise is at 05:40 and sunset at 17:57. On the last day of December, sunrise is at 05:54 and sunset at 18:12 -04.
The average sunshine in December in Manaus, Brazil
, is 4.2h.
through December, with an average maximum UV index of 12, are months with the highest UV index in Manaus. A UV Index estimate of 11, and higher, represents an extreme health hazard from unsafe exposure to UV radiation for the average person.Note
: The daily maximum UV index of 12 in December interpret into the following advice:
Take all required precautions, as unprotected skin and eyes can burn in minutes. The Sun's UV radiation is most powerful between 10 a.m. and 4 p.m. To the extent possible, limit exposure to the direct sun during these hours. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects. Even on cloudy days, a sunscreen with a minimum 30 sun protection factor should be generously applied and frequently re-applied, including after every swim or outdoor exercise.