September weather forecast
Usulutan, El Salvador

September in Usulutan is characterized by heavy rainfall — up to 182mm (7.17"). As the city ventures deeper into the wet season, temperatures continue to descend subtly. There's a notable decrease in daylight matching the reduced amount of sunshine, contributing to the overall gloomy weather conditions. As September progresses, average wind conditions tend to remain steady. Cloud coverage significantly increases during this month due to the heightened rainfall.

Temperature

As August transitions into September, Usulutan records an average high-temperature of a still tropical 30.2°C (86.4°F), showing a gentle shift from the preceding month. Usulutan throughout September, experiences an average nighttime temperature of 22.9°C (73.2°F).

Heat index

Throughout September, the heat index is appraised at a sweltering 39°C (102.2°F). Take greater precautions, heat exhaustion and heat cramps may be expected. Heatstroke could result from lengthy activity.
Realize that the values for the heat index are set for shaded places and light winds. 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 'apparent temperature', is a composite of temperature and humidity figures to convey how warm it feels. One's perception of weather can be shaped by other factors, involving metabolic differences, pregnancy, and physical exertion. Taking into account that direct sunlight can boost the heat effect, the heat index may rise by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are primarily vital for children. Children frequently underestimate the importance of resting and drinking fluids. Thirst is a symptom of advanced dehydration - hence the need to hydrate regularly, especially during protracted physical exercises.
Evaporating sweat, an outcome of perspiration, is key in assisting the human body to moderate its temperature. A surge in relative humidity can disrupt the body's normal cooling function by slowing evaporation, hence reducing the rate at which the body cools and intensifying the perception of heat. Increasing body temperatures can be a precursor to dehydration if the body can't shed the extra heat.

Humidity

In September, the average relative humidity is 82%.

Rainfall

In Usulutan, during September, the rain falls for 27.5 days and regularly aggregates up to 182mm (7.17") of precipitation. In Usulutan, during the entire year, the rain falls for 206.2 days and collects up to 1242mm (48.9") of precipitation.

Daylight

The average length of the day in September in Usulutan is 12h and 12min.
On the first day of the month, sunrise is at 05:42 and sunset at 18:04. On the last day of September, sunrise is at 05:43 and sunset at 17:43 CST.

Sunshine

In Usulutan, the average sunshine in September is 8.8h.

UV index

The months with the highest UV index are January through September and December, with an average maximum UV index of 7. A UV Index value of 6 to 7 symbolizes a high threat to health from unsafe exposure to UV radiation for the average person.
Note: The maximum daily UV index of 7 in September interprets into the following recommendations:
Use measures and accept sun safety conventions. Guarding against skin and eye trauma is of high priority. Limit your exposure to the sun's UV radiation, which is strongest between 10 a.m. and 4 p.m., and note that parasols or canopies may not provide full sun protection. Sunglasses that guard against UVA and UVB rays are pivotal in minimizing sun-induced ocular damage.