September weather forecastAlcântara, Brazil
September
Weather in September
September, the first month of the spring in Alcântara, is still a tropical month, with an average temperature varying between 25.3°C (77.5°F) and 30.6°C (87.1°F).Temperature
The advent of September brings an average high-temperature of a still hot 30.6°C (87.1°F), almost identical to the preceding month. During September, Alcântara sees a mean low-temperature of 25.3°C (77.5°F).Heat index
The heat index value for September is estimated at a fiery hot 38°C (100.4°F). Take more safety measures, heat exhaustion and heat cramps are potential outcomes. Persistent activity might lead to heatstroke.Heat index evaluations are typically in the context of light winds and shaded environments. The heat index might be elevated by 15 Fahrenheit (8 Celsius) degrees due to direct sun exposure.
Note: The heat index, also known as 'felt air temperature' or 'apparent temperature', unifies temperature and humidity readings to offer a comprehensive feel of warmth. The experience of temperature can be subjective, varying based on the individual's activity and heat perception, influenced by factors like wind, attire, and metabolic variations. Taking into account that direct sunlight can boost the heat effect, the heat index may rise by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly relevant to babies and toddlers. Kids generally face higher risks than adults as they sweat less. Along with their large skin surface compared to their small bodies and higher heat production due to their activities, their vulnerability is increased.
The evaporation of sweat is a natural cooling mechanism of the human body, facilitated by perspiration. In the presence of elevated relative humidity, the evaporation rate decreases. This reduction leads to increased body heat retention compared to conditions of dry air. Should the body fail to balance its heat gain, the escalating temperature poses health challenges.
Humidity
The months with the lowest humidity are September through November, with an average relative humidity of 75%.Rainfall
In Alcântara, in September, during 14.1 rainfall days, 33mm (1.3") of precipitation is typically accumulated. In Alcântara, during the entire year, the rain falls for 291.1 days and collects up to 2596mm (102.2") of precipitation.Sea temperature
September is the month with the coldest seawater in Alcântara, with an average sea temperature of 27.4°C (81.3°F).Note: For swimming, diving, or other water activities, the temperature range of 25°C (77°F) to 29°C (84.2°F) is perceived as exceptionally enjoyable and comfortable even for prolonged periods.
Daylight
The average length of the day in September in Alcântara is 12h and 6min.On the first day of September, sunrise is at 05:55 and sunset at 17:59. On the last day of the month, sunrise is at 05:43 and sunset at 17:51 -03.
Sunshine
In September, the average sunshine in Alcântara is 8.1h.UV index
April, June through November, 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 risk from exposure to the Sun's UV radiation for the average person.Note: A typical high UV index of 7 in September suggests the following recommendations:
Shield from overexposure. Defense against sun-related harm is required. Stay out of direct sunlight between 10 a.m. and 4 p.m., when UV radiation is most intense, and remember that not all shade structures provide complete protection. Wearing a wide-brim hat can block approximately 50% of UV radiation, protecting the eyes. Take caution! The UV rays from the Sun gain strength from sand and water reflections.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Alcântara, Brazil
- Average high temperature in September: 30.6°C
The warmest month (with the highest average high temperature) is October (31.1°C).
The month with the lowest average high temperature is February (29.1°C).
- Average low temperature in September: 25.3°C
The month with the highest average low temperature is November (26°C).
The coldest month (with the lowest average low temperature) is July (24.2°C).
Average pressure in September
Alcântara, Brazil
- Average pressure in September: 1011.8mbar
The month with the highest atmospheric pressure is July (1013mbar).
The month with the lowest atmospheric pressure is November (1009.3mbar).
Average wind speed in September
Alcântara, Brazil
- Average wind speed in September: 16.8km/h
The windiest month (with the highest average wind speed) is October (17.9km/h).
The calmest month (with the lowest average wind speed) is May (10.2km/h).
Average humidity in September
Alcântara, Brazil
- Average humidity in September: 75%
The months with the highest relative humidity are April and May (84%).
The months with the lowest relative humidity are September, October and November (75%).
Average rainfall in September
Alcântara, Brazil
- Average rainfall in September: 33mm
The wettest month (with the highest rainfall) is April (438mm).
The driest month (with the least rainfall) is October (29mm).
Average rainfall days in September
Alcântara, Brazil
- Average rainfall days in September: 14.1 days
The month with the highest number of rainy days is March (30.7 days).
The month with the least rainy days is October (13.6 days).
Average sea temperature in September
Alcântara, Brazil
- Average sea temperature in September: 27.4°C
The best month for swimming (with the highest average sea temperature) is March (29°C).
The coldest month (with the lowest average sea temperature) is September (27.4°C).
Average daylight in September /
Average sunshine in September
Alcântara, Brazil
- Average daylight in September: 12h and 6min
The month with the longest days is December (Average daylight: 12h and 18min).
The month with the shortest days is June (Average daylight: 12h and 0min).
- Average sunshine in September: 8h and 6min
The month with the most sunshine is August (Average sunshine: 9h and 24min).
The month with the least sunshine is November (Average sunshine: 7h and 6min).
Average sunshine days in September
Alcântara, Brazil
- Average sunshine days in September: 11.4 days
The month with the most sunshine days is October (12.6 days).
The month with the least sunshine days is February (0 days).
Average UV index in September
Alcântara, Brazil
- Average UV index in September: 7
The months with the highest UV index are April, June, July, August, September, October and November (UV index 7).
The months with the lowest UV index are January, February, March, May and December (UV index 6).
Average cloud cover in September
Alcântara, Brazil
- Average cloud cover in September: 33
The month with the most cloud cover is March (Cloud cover 50).
The month with the least cloud cover is August (Cloud cover 28).
Average visibility in September
Alcântara, Brazil
- Average visibility in September: 10km
The months with the highest visibility are August, September, October, November and December (10km).
The months with the lowest visibility are January, February, March, April, May, June and July (9km).





