September Weather in Porto Uniao, Brazil

Last updated: August 22, 2025

In September, the average temperature in Porto Uniao, Brazil is a comfortable 18°C (64°F). However, be prepared for a range of temperatures, as it can dip to a chilly 3°C (38°F) and soar to a warm 32°C (90°F). Rainfall is not uncommon, with an average precipitation of 71 mm (2.8 in) spread over 9 days. With an average humidity of 75%, it's a month that balances warmth with a touch of moisture in the air.

September Temperature in Porto Uniao

In September in Porto Uniao, the average temperature is 18°C (64°F), with maximums reaching up to 32°C (90°F) and minimums dipping down to 3°C (38°F). This wide temperature range makes it advisable for travelers to pack for both warm days and cooler nights.

September Weather in Porto Uniao: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Porto Uniao, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Porto Uniao, September typically has an average temperature of 18°C (64°F), with highs reaching up to 32°C (90°F) and lows dropping to around 3°C (38°F).

Data source: Temperature data for Porto Uniao generated using information from the Copernicus Climate Change Service.

September Precipitation in Porto Uniao

In Porto Uniao in September, the precipitation amount is 71 mm (2.8 in) spread over 9 days.

September Precipitation Trends in Porto Uniao

The chart displays monthly precipitation patterns in Porto Uniao, with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In Porto Uniao, September typically receives around 71 mm (2.8 inches) of precipitation spread over approximately 9 days.

Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

September Humidity in Porto Uniao

In Porto Uniao in September, humidity is 75%. With an average temperature of 18°C (64°F), this humidity feels like a warm blanket enveloping you, making your travels a bit sticky and requiring frequent breaks in the shade to stay comfortable.

September Average Humidity in Porto Uniao

This chart illustrates the average monthly humidity levels in Porto Uniao, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Porto Uniao is approximately 75%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Porto Uniao

In Porto Uniao in September, the maximum UV index reaches 11, which corresponds to an extreme Exposure Category. With a time to burn of just 10 minutes, it's essential to take precautions. For more details, you can check the Hourly UV Index in Porto Uniao.

Maximum UV Index Levels in Porto Uniao for September

The chart shows the monthly maximum UV Index (UVI) for Porto Uniao in September, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In September, the maximum UV index in Porto Uniao typically reaches 11, which falls under the extreme exposure category.

Data source: Porto Uniao September UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

Extreme (11+): Avoid the sun, stay in shade.
Very High (8-10): Limit sun exposure.
High (6-7): Use SPF 30+ and protective clothing.
Moderate (3-5): Midday shade recommended.
Low (0-2): No protection needed.

How September Weather in Porto Uniao Compares to Other Months

Weather in Porto Uniao varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Porto Uniao, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in Porto Uniao, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	21°C (70°F)	143 mm (5.6 inches)	85%	extreme
February Weather	21°C (70°F)	102 mm (4.0 inches)	81%	extreme
March Weather	20°C (69°F)	99 mm (3.9 inches)	82%	extreme
April Weather	17°C (64°F)	56 mm (2.2 inches)	84%	extreme
May Weather	15°C (59°F)	82 mm (3.2 inches)	86%	high
June Weather	14°C (57°F)	95 mm (3.7 inches)	84%	high
July Weather	13°C (55°F)	25 mm (1.0 inches)	77%	high
August Weather	14°C (57°F)	75 mm (3.0 inches)	70%	very high
September Weather	18°C (64°F)	71 mm (2.8 inches)	75%	extreme
October Weather	18°C (64°F)	140 mm (5.5 inches)	76%	extreme
November Weather	19°C (67°F)	115 mm (4.5 inches)	84%	extreme
December Weather	21°C (70°F)	133 mm (5.2 inches)	88%	extreme