January weather forecast
San Marcos, El Salvador

Beginning the year, San Marcos, El Salvador sees a shift in weather conditions from the chilly season of December. January exhibits clear skies with only 13% cloud cover, offering brilliant sunshine for an approximate seven hours. The nights may feel noticeably cooler compared to the heat experienced in December, particularly during the early mornings. Hikers and outdoor enthusiasts might find this time of year ideal for an early morning exercise session. January records relatively minimal rainfall with an average of 2mm (0.08") over just over two days.

Temperature

January's average high-temperature is a still hot 31.2°C (88.2°F), maintaining a close comparison with December's 30.8°C (87.4°F). San Marcos undergoes a major shift from daytime highs, averaging a refreshing 19°C (66.2°F) during the night in January.

Heat index

January's heat index is computed to be a sweltering 36°C (96.8°F). Implement additional preventive actions, heat cramps and heat exhaustion are potential hazards. Heatstroke could follow prolonged activity.
Records show heat index calculations are tailored for shaded regions and mild winds. Exposure to the sun directly might heighten the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'apparent temperature', ties air temperature with relative humidity to produce the perceived temperature sensation. The effect is personal, with varied weather perceptions among individuals due to differences in body mass, stature, and physical activity. When in direct sunlight, one should be cautious as it can raise the heat index by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values hold great significance to children. Young children are more at risk than adults since they tend to sweat less. Moreover, their large skin surface in proportion to their small bodies and the high heat production due to their activities contribute to their vulnerability.
The innate cooling system of the human body revolves around perspiration, with the evaporation of sweat being central to this process. In conditions of both high temperature and humidity (a high heat index), sweating is limited and the perception of heat is enhanced. Overheating can ensue when the body accumulates more heat than it can release, and dehydration severity may vary.

Humidity

The average relative humidity in January in San Marcos, El Salvador, is 64%.

Rainfall

The month with the least rainfall is January, when the rain falls for 2.3 days and typically collects 2mm (0.08") of precipitation.

Daylight

In January, the average length of the day in San Marcos is 11h and 26min.
On the first day of the month, sunrise is at 06:19 and sunset at 17:40. On the last day of January, sunrise is at 06:23 and sunset at 17:56 CST.

Sunshine

The months with the least sunshine in San Marcos, El Salvador, are January and December, with an average of 7.7h of sunshine.

UV index

The months with the highest UV index are January through April, with an average maximum UV index of 7. A UV Index of 6 to 7 symbolizes a high health hazard from unsafe exposure to UV radiation for the average person.
Note: In January, the maximum UV index of 7 suggests these recommendations:
Evade overexposure. Individuals with fair skin risk burning in under 20 minutes. The Sun's UV radiation is most potent between 10 a.m. and 4 p.m. Try to limit direct exposure to the Sun during this period. Experience reduced UV exposure by about half when donning a wide-brim hat.