September weather forecast
Boca Barranca, Costa Rica

September, the first month of the autumn in Boca Barranca, is still a warm month, with an average temperature fluctuating between 28.9°C (84°F) and 23.2°C (73.8°F).

Temperature

September observes an average high-temperature of a still moderately hot 28.9°C (84°F), marking an insignificant difference from August's 29.4°C (84.9°F). An average nighttime temperature of 23.2°C (73.8°F) is witnessed in Boca Barranca throughout September.

Heat index

In September, the average heat index is evaluated at a torrid 35°C (95°F). Heightened safety actions are necessary, heat cramps and heat exhaustion are probable. Persistent activity may lead to heatstroke.
Note that heat index values are valued for light wind and location in the shade. Direct sunlight exposure may result in a rise of the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature' or 'apparent temperature', is a numerical representation of warmth when taking temperature and moisture levels into account. The influence of weather is personal, with a diverse population experiencing it differently due to differences in body mass, stature, and degree of activity. You should know that direct sun exposure can heighten weather effects, potentially elevating the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are essentially critical for children. Children are often less aware of the need to rest and re-hydrate. Thirst is a late sign of dehydration - it's vital to remain hydrated, particularly during prolonged physical activities.
For the human body, perspiration is the go-to method to regulate temperature, using sweat's evaporation to dissipate warmth. 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. When heat gain surpasses the level the body can shed, body temperature begins to increase, and consequently, overheating and dehydration can occur, with varying severity.

Humidity

The average relative humidity in September in Boca Barranca is 82%.

Rainfall

In Boca Barranca, in September, during 27.7 rainfall days, 193mm (7.6") of precipitation is typically accumulated. In Boca Barranca, during the entire year, the rain falls for 218.6 days and collects up to 1456mm (57.32") of precipitation.

Daylight

In Boca Barranca, the average length of the day in September is 12h and 11min.
On the first day of September in Boca Barranca, sunrise is at 05:29 and sunset at 17:47. On the last day of the month, sunrise is at 05:27 and sunset at 17:29 CST.

Sunshine

In September, the average sunshine is 8.7h.

UV index

January through September and December, with an average maximum UV index of 7, are months with the highest UV index. A UV Index estimate of 6 to 7 represents a high health vulnerability from unprotected exposure to Sun's UV rays for the average person.
Note: A maximum UV index of 7 in September translates into the following recommendations:
Resist extreme sun exposure. Guarding against solar damage is essential. During the period from 10 a.m. to 4 p.m., UV radiation is highest. Try to avoid direct sunlight during these hours. A wide-brimmed hat is a shield, deflecting up to 50% of harmful UV radiation from eyes.