September weather forecast
Riacho Frio, Brazil

September, the first month of the spring in Riacho Frio, is still a tropical month, with an average temperature varying between 20.5°C (68.9°F) and 34.9°C (94.8°F).

Temperature

September's arrival registers an average high-temperature of a still hot 34.9°C (94.8°F), closely aligning with the temperature of the previous month. Riacho Frio's average low-temperature for the month of September denotes a significant decline from the daily high, recording at a pleasant 20.5°C (68.9°F).

Heat index

September's heat index is estimated at a sweltering 37°C (98.6°F). Take special precautions - heat exhaustion and heat cramps are expected. Heatstroke may occur with lengthy activity.
Note that heat index values are valued for light wind and location in the shade. The heat index can potentially augment by 15 Fahrenheit (8 Celsius) degrees due to direct sunlight.
Note: The heat index, also known as 'real feel' or 'feels like', combines both the air temperature and the humidity level to give a perceived human temperature. This impact is subjective, influenced by the person's physical activity and individual heat perception, affected by factors including wind, attire, and metabolic differences. Always consider that direct sunlight exposure might heighten the heat's effects, pushing the heat index up by 15 Fahrenheit (8 Celsius) degrees. Heat index values are quite important for babies and toddlers. Kids are usually in more danger than grown-ups as they tend to sweat less. Plus, their bigger skin surface in relation to their small frames and increased heat generation due to their activity level make them more susceptible.
The human body normally cools itself by perspiration. Excessive warmth is eliminated from the body by evaporation of sweat. Increased relative humidity slows down evaporation, thereby decreasing the rate of heat removal from the body, culminating in a sensation of overheating. Overheating dangers loom when the body's heat release mechanisms are overshadowed by excessive gain.

Humidity

With an average relative humidity of 40%, September is the least humid month.

Rainfall

Months with rainfall are January through July, September through December. September is the first month it rains in Riacho Frio. Throughout September, in the average 1.3 rainfall days, it receives 5mm (0.2") of precipitation. In Riacho Frio, during the entire year, the rain falls for 134.3 days and collects up to 578mm (22.76") of precipitation.

Daylight

The average length of the day in September is 12h and 3min.
On the first day of the month, sunrise is at 06:01 and sunset at 17:57. On the last day of September, sunrise is at 05:43 and sunset at 17:55 -03.

Sunshine

In September, the average sunshine is 9.6h.

UV index

August through October, with an average maximum UV index of 7, are months with the highest UV index in Riacho Frio. A UV Index value of 6 to 7 symbolizes a high health hazard from unprotected exposure to Sun's UV rays for the ordinary person.
Note: In September, the UV index of 7 transforms into the following advice:
Persist with precautions and heed sun safety advice. Prevention of sunburn is compulsory. Avoid direct exposure to the Sun between 10 a.m. and 4 p.m., the peak period for UV radiation, noting that objects like parasols or canopies might not offer complete sun protection. Wearing a wide-brim hat can block approximately 50% of UV radiation, protecting the eyes.