December weather forecast
Santo Tomás, El Salvador

The first month of the winter, December, is still a hot month in Santo Tomás, El Salvador, with an average temperature fluctuating between 19.1°C (66.4°F) and 30.8°C (87.4°F).

Temperature

Santo Tomás's average high-temperature in December is a still tropical 30.8°C (87.4°F), indicating a subtle variation from November. In December, Santo Tomás encounters an average low-temperature of 19.1°C (66.4°F) during the night.

Heat index

The heat index for December is estimated at a fiery hot 37°C (98.6°F). Preventive measures are required to mitigate the risk of heat cramps and heat exhaustion. Continuous activity may precipitate heatstroke.
Note that heat index values are valued for light wind and location in the shade. Exposure to direct sunlight may make the heat index values climb by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'feels like', is achieved by amalgamating air temperature with the relative humidity readings. Additional elements including metabolic differences, the level of physical activity, and attire have a role in shaping the individual's temperature perception. One must note that being under the direct sun can escalate the heat's effects, with the heat index possibly rising by 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely significant for babies and toddlers. Children typically face more danger than adults as their sweat production is usually lower. Additionally, the bigger skin surface compared to their small size and the increased heat due to their activeness exacerbate the risk.
Perspiration and the resultant sweat evaporation are the body's natural thermostat, helping regulate temperature. An elevated level of relative humidity hinders evaporation, leading to decreased heat elimination from the body, inducing a sensation of excess heat. When heat surpasses the body's release mechanisms, dehydration and overheating risks become pronounced.

Humidity

The average relative humidity in December is 69%.

Rainfall

In Santo Tomás, during December, the rain falls for 2.8 days and regularly aggregates up to 6mm (0.24") of precipitation. In Santo Tomás, during the entire year, the rain falls for 196.7 days and collects up to 1216mm (47.87") of precipitation.

Daylight

With an average of 11h and 18min of daylight, December has the shortest days of the year.
On the first day of December, sunrise is at 06:04 and sunset at 17:27. On the last day of the month, sunrise is at 06:19 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 Santo Tomás, El Salvador.

UV index

The months with the lowest UV index in Santo Tomás, El Salvador, are May through December, with an average maximum UV index of 6. A UV Index of 6 to 7 symbolizes a high health hazard from unsafe exposure to UV radiation for the ordinary person.
Note: A typical high UV index of 6 in December suggests the following recommendations:
Deter overexposure. Protecting against the sun's effects is essential. Limit direct sun exposure especially between 10 a.m. and 4 p.m., when UV radiation is at its peak. However, keep in mind that shade structures may not provide full sun protection. Tightly woven clothing, when worn loosely, shields effectively against the Sun.