September weather forecast
Opico, El Salvador

The first month of the autumn, September, is also a moderately hot month in Opico, El Salvador, with temperature in the range of an average low of 21.5°C (70.7°F) and an average high of 29.8°C (85.6°F).

Temperature

September's arrival brings an average high-temperature of a warm 29.8°C (85.6°F), demonstrating subtle variation from the preceding month. An average nighttime temperature of 21.5°C (70.7°F) is noted during the month of September.

Heat index

The heat index for September is appraised at a very hot 38°C (100.4°F). Greater safety measures are needed, risk of heat exhaustion and heat cramps is high. Continuous activity might trigger heatstroke.
It is essential to grasp that the heat index's numbers are for shade and light wind settings. Direct sunlight can potentially boost the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'felt air temperature', is a numerical representation of warmth when taking temperature and moisture levels into account. One's perception of temperature can vary depending on physical activity and individual heat sensitivity, influenced by factors like wind, attire, and metabolic variations. Given direct exposure to sunlight, one might experience a rise in the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values hold particular significance for children. Young ones often underestimate the need for rest and rehydration. Thirst appears late in dehydration - hence, it is important to keep hydrated, particularly during prolonged physical activities.
The process of perspiration is vital for the human body to get rid of excess warmth by allowing sweat to evaporate. Greater relative humidity lessens the rate of evaporation, thus decreasing the body's heat dispersal, which gives rise to a sensation of overheating. Heat absorption that surpasses the body's shedding capability can lead to overheating and varying levels of dehydration.

Humidity

September and October, with an average relative humidity of 82%, are the most humid months.

Rainfall

In Opico, in September, it is raining for 26.3 days, with typically 142mm (5.59") of accumulated precipitation. In Opico, El Salvador, during the entire year, the rain falls for 187 days and collects up to 1106mm (43.54") of precipitation.

Daylight

In Opico, the average length of the day in September is 12h and 12min.
On the first day of the month, sunrise is at 05:45 and sunset at 18:08. On the last day of September, sunrise is at 05:46 and sunset at 17:47 CST.

Sunshine

In September, the average sunshine is 9.3h.

UV index

The months with the lowest UV index in Opico are January, May, June, August through December, with an average maximum UV index of 6. A UV Index value of 6 to 7 symbolizes a high health vulnerability from unsafe exposure to UV radiation for the ordinary person.
Note: The daily high UV index of 6 during September translates into the following recommendations:
Implement precautions and maintain sun safety methods. Avoidance of sunburn is demanded. Avoid direct sunlight between the hours of 10 a.m. and 4 p.m., when UV radiation is at its peak. Keep in mind that shade structures may not provide complete protection. For a sun-safe wardrobe, go for clothes that are tightly woven and generously sized.