September weather forecast
Chalchuapa, El Salvador

September in Chalchuapa is characterized by the highest amounts of cloud cover, recording at 57%. Following the trend from previous months, the weather stays wet with frequent bouts of rain, while the average high temperature creeps to a cooler 29.3°C (84.7°F). While this month makes a step back towards more sunshine than the preceding August, it is still markedly low. Take this time to appreciate the cooler temperatures and thriving fauna that this weather precipitates.

Temperature

Entering September in Chalchuapa, the average high-temperature is recorded at a moderately hot 29.3°C (84.7°F), exhibiting a minimal shift from August's 30°C (86°F). In September, Chalchuapa experiences a temperature dip to an average of 18.9°C (66°F) at night.

Heat index

Throughout September, the heat index is computed to be a sweltering 37°C (98.6°F). Greater preventive actions are needed, heat exhaustion and heat cramps are likely. Persistent activity could provoke heatstroke.
In terms of the heat index, values are set with light wind and shade conditions in mind. With direct sunlight, the heat index could increase by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'apparent temperature', is derived by integrating air temperature with the existing relative humidity to express the perceived warmth. A person's impression of weather can be swayed by numerous aspects, among them metabolic variations, pregnancy, and activity levels. Consider that direct sun exposure can intensify the felt heat, adding potentially 15 Fahrenheit (8 Celsius) degrees to the heat index. Heat index values are quite important 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.
Perspiring is a crucial mechanism for the human body, allowing it to release excessive warmth through evaporating sweat. Under high air temperature coupled with high humidity (high heat index), the body's perspiration is reduced, intensifying the sensation of heat. When heat gain exceeds the level the body can remove, body temperature begins to rise, and heat-related illnesses and disorders may develop.

Humidity

The average relative humidity in September in Chalchuapa is 85%.

Rainfall

In Chalchuapa, in September, during 24.7 rainfall days, 141mm (5.55") of precipitation is typically accumulated. In Chalchuapa, during the entire year, the rain falls for 181.4 days and collects up to 1055mm (41.54") of precipitation.

Daylight

The average length of the day in September is 12h and 12min.
On the first day of September in Chalchuapa, sunrise is at 05:47 and sunset at 18:09. On the last day of the month, sunrise is at 05:48 and sunset at 17:48 CST.

Sunshine

In Chalchuapa, the average sunshine in September is 7.8h.

UV index

The month with the lowest UV index is September, with an average maximum UV index of 5. A UV Index reading of 3 to 5 represents a moderate health risk from exposure to the Sun's UV radiation for the ordinary person.
Note: The maximum UV index of 5 during September translates into these guidelines:
Undertake precautions - Obligation exists to protect against skin and eye damage. The Sun is at its harshest during midday; protect yourself by staying in shaded areas and minimizing exposure. Tightly woven clothing, when worn loosely, shields effectively against the Sun.