September signals the commencement of warmer months for
Santa Cruz de la Sierra, as the average high temperature climbs up to 29.4°C (84.9°F). This period also witnesses an upward trend in rainfall, marking an end to the driest part of the year. Despite the increase in precipitation levels, the weather remains comfortable throughout the month. Simultaneously, daylight hours increase, thus extending the time available for outdoor recreation.
Temperature
The average high-temperature in September in Santa Cruz de la Sierra,
Bolivia, at a still moderately hot 29.4°C (84.9°F), reveals a modest deviation from
August's 27.7°C (81.9°F). Santa Cruz de la Sierra's nights in September experience an average temperature drop to a comfortable 18.7°C (65.7°F).
Heat index
The heat index value for September is estimated at a tropical 32°C (89.6°F). Uninterrupted activity during exposure could lead to a sense of exhaustion, possibly causing heat cramps.
Regarding the heat index, one should be aware it's determined by shaded settings and mild winds. The heat index could see an increase by 15 Fahrenheit (8 Celsius) degrees under direct sunshine.
Note: The heat index, also known as 'felt air temperature' or 'apparent temperature', is what the temperature feels like to the human body when the air temperature is combined with the relative humidity. Elements such as metabolic variations, pregnancy, and physical exertion can influence one's weather perception. When exposed to direct sunlight, it's possible for the heat index to increase by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values are essentially critical for children. Typically, children face more danger than adults as they usually perspire less. Their larger skin surface relative to their small bodies and increased heat output from their activities enhance their risk.
Humidity
The least humid month is September, with an average relative humidity of 64%.
Rainfall
In Santa Cruz de la Sierra, in September, it is raining for 5.6 days, with typically 58mm (2.28") of accumulated precipitation. Throughout the year, there are 111.6 rainfall days, and 1322mm (52.05") of precipitation is accumulated.
Daylight
In September, the average length of the day is 12h and 1min.
On the first day of the month, sunrise is at 06:19 and sunset at 18:05. On the last day of September, sunrise is at 05:54 and sunset at 18:10 -04.
Sunshine
In Santa Cruz de la Sierra, the average sunshine in September is 8h.
UV index
In Santa Cruz de la Sierra, the average daily maximum UV index in September is 11. A UV Index of 11, and more, symbolizes an extreme health hazard from unsafe exposure to UV radiation for the ordinary person.
Note: The daily high UV index of 11 in September translates into this advice:
Ensure all key precautions. Defense against sun exposure is critical. Avoid direct Sun exposure from 10 a.m. to 4 p.m., a period when UV radiation is most intense, and remember that not all shade structures provide full protection. A hat with a generous brim can prevent nearly 50% of UV rays from reaching your eyes. Even on cloudy days, a sunscreen with a minimum 30 sun protection factor should be generously applied and frequently re-applied, including after every swim or outdoor exercise.