December weather forecast
Opico, El Salvador

The first month of the winter, December, is also a moderately hot month in Opico, El Salvador, with an average temperature varying between 19.5°C (67.1°F) and 29.9°C (85.8°F).

Temperature

The dawn of December registers an average high temperature of a still moderately hot 29.9°C (85.8°F), nearly the same as the a warm 29.9°C (85.8°F) observed in November. In December, Opico experiences a temperature dip to an average of 19.5°C (67.1°F) at night.

Heat index

For most parts of December, the heat index is appraised at a torrid 35°C (95°F). Extra safeguards are necessary to prevent heat exhaustion and heat cramps. Prolonged activity might cause heatstroke.
Be aware that heat index ratings are designed for shaded locations and minor breezes. Exposing to direct sunshine may enhance heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'apparent temperature', combines both the air temperature and the humidity level to give a perceived human temperature. This effect tends to be personal, with the weather perception differing among individuals due to variations in body mass, height, and exertion. Exposure to direct sun rays can influence the heat you feel, pushing the heat index up by 15 Fahrenheit (8 Celsius) degrees. Heat index values hold great significance to children. Young ones are generally more prone to risk than adults due to their reduced ability to sweat. Their large skin surface area relative to their diminutive bodies and elevated heat production from their activities further enhance this risk.
The physiological response of the human body to excess warmth is to perspire, thereby cooling itself through sweat evaporation. An upsurge in relative humidity affects normal body cooling mechanisms by slowing evaporation, hence reducing the rate at which the body cools and intensifying the perception of heat. When heat surpasses the body's release mechanisms, dehydration and overheating risks become pronounced.

Humidity

In December, the average relative humidity is 70%.

Rainfall

In Opico, in December, it is raining for 2.3 days, with typically 4mm (0.16") of accumulated precipitation. Throughout the year, in Opico, there are 187 rainfall days, and 1106mm (43.54") of precipitation is accumulated.

Daylight

With an average of 11h and 18min of daylight, December has the shortest days of the year.
On the first day of the month, sunrise is at 06:05 and sunset at 17:27. On the last day of December, sunrise is at 06:21 and sunset at 17:40 CST.

Sunshine

January and December, with an average of 7.7h of sunshine, are months with the least sunshine in Opico.

UV index

January, May, June, August through December, with an average maximum UV index of 6, are months with the lowest UV index. A UV Index reading of 6 to 7 represents a high health hazard from exposure to the Sun's UV rays for the ordinary person.
Note: An average maximum UV index of 6 in December leads to these recommendations:
Follow precautions and abide by sun safety rules. Deterrence of sunburn is imperative. 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. For excellent sun protection for the eyes, ears, face, and neck, consider a wide-brim hat.