December weather forecast
San Francisco Lempa, El Salvador

The first month of the winter, December, is still a tropical month in San Francisco Lempa, El Salvador, with an average temperature ranging between max 30.8°C (87.4°F) and min 18.6°C (65.5°F).

Temperature

December brings an average high-temperature of a still tropical 30.8°C (87.4°F), showing a slight difference from November's 30.5°C (86.9°F). Nightly readings in December display a noticeable downturn from daily highs, with the average low-temperature registering a refreshing 18.6°C (65.5°F).

Heat index

The heat index value for December is appraised at a very hot 37°C (98.6°F). Adopt enhanced safety measures, heat exhaustion and heat cramps could occur. Continuous activity may induce heatstroke.
Observations indicate that the heat index values are for shady locations with light wind. Heat index values may rise by up to 15 Fahrenheit (8 Celsius) degrees when exposed to direct sunlight.
Note: The heat index, also known as 'feels like' or 'real feel', comes about by integrating the temperature readings with the humidity levels. A person's impression of weather can be swayed by numerous aspects, among them metabolic variations, pregnancy, and activity levels. It is essential to realize that direct sunlight can escalate the perceived temperature, increasing the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are quite important for babies and toddlers. Kids are usually in more danger than grown-ups as they tend to sweat less. Plus, their bigger skin surface in relation to their small frames and increased heat generation due to their activity level make them more susceptible.
To combat high temperatures, the human body perspires and relies on sweat evaporation for cooling. In situations of high air temperature combined with high humidity (significant heat index), the body's ability to perspire is reduced, heightening the sense of warmth. With body temperatures on the rise, inefficient heat shedding can lead to dehydration and its associated complications.

Humidity

In San Francisco Lempa, the average relative humidity in December is 69%.

Rainfall

In San Francisco Lempa, during December, the rain falls for 3.3 days and regularly aggregates up to 5mm (0.2") of precipitation. Throughout the year, there are 192.2 rainfall days, and 1062mm (41.81") of precipitation is accumulated.

Daylight

December has the shortest days of the year in San Francisco Lempa, with an average of 11h and 18min of daylight.
On the first day of December in San Francisco Lempa, sunrise is at 06:04 and sunset at 17:26. On the last day of the month, sunrise is at 06:19 and sunset at 17:38 CST.

Sunshine

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

UV index

The months with the lowest UV index are January, June through December, with an average maximum UV index of 6. A UV Index reading of 6 to 7 represents a high health risk from exposure to the Sun's UV radiation for ordinary individuals.
Note: A maximum daily UV index of 6 during December morphs into the following directions:
Take precautions against overexposure. Fair-skinned people may get burned in less than 20 minutes. The Sun's UV radiation is at its strongest between the hours of 10 a.m. and 4 p.m. Minimize direct exposure to the sun during this period. For a sun-safe wardrobe, go for clothes that are tightly woven and generously sized.