September Weather in Mertola, Portugal

Last updated: August 27, 2025

In September, the average temperature in Mertola, Portugal is a comfortable 23°C (74°F). However, expect a range in temperatures, with minimums dipping to 11°C (51°F) and maximums soaring up to 38°C (101°F). The month typically sees 22 mm (0.8 in) of precipitation over two days, contributing to an average humidity level of 71%.

September Temperature in Mertola

In September in Mertola, the average temperature is 23°C (74°F). Maximum temperatures can reach 38°C (101°F), while minimum temperatures can drop to as low as 11°C (51°F). This varied climate makes it a great time to explore the outdoors, so pack accordingly for both warm days and cool evenings.

September Weather in Mertola: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Mertola, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Mertola, September typically has an average temperature of 23°C (74°F), with highs reaching up to 38°C (101°F) and lows dropping to around 11°C (51°F).

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

September Precipitation in Mertola

In Mertola in September, the total precipitation amount is 22 mm (0.8 in) over a span of 2 days.

September Precipitation Trends in Mertola

The chart displays monthly precipitation patterns in Mertola, 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 Mertola, September typically receives around 22 mm (0.8 inches) of precipitation spread over approximately 2 days.

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

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Millimeters (mm) Inches (in)

September Humidity in Mertola

In Mertola in September, humidity is 71%. With an average temperature of 23°C (74°F), this humidity feels like a warm, enveloping embrace that can make outdoor activities feel sticky, but if you're well-hydrated and take breaks in the shade, it offers a pleasant tropical ambiance perfect for exploration.

September Average Humidity in Mertola

This chart illustrates the average monthly humidity levels in Mertola, 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 Mertola is approximately 71%, 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 Mertola

In Mertola in September, the maximum UV index is 9, which corresponds to a very high Exposure Category. The time to burn is just 15 minutes, so it's essential to take precautions. For detailed information, you can check the Hourly UV Index in Mertola.

Maximum UV Index Levels in Mertola for September

The chart shows the monthly maximum UV Index (UVI) for Mertola 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 Mertola typically reaches 9, which falls under the very high exposure category.

Data source: Mertola 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 Mertola Compares to Other Months

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

This table compares monthly weather conditions in Mertola, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	9°C (49°F)	23 mm (0.9 inches)	80%	moderate
February Weather	12°C (54°F)	37 mm (1.5 inches)	73%	moderate
March Weather	13°C (56°F)	67 mm (2.7 inches)	71%	high
April Weather	15°C (60°F)	55 mm (2.2 inches)	69%	very high
May Weather	20°C (68°F)	26 mm (1.0 inches)	69%	very high
June Weather	22°C (72°F)	9 mm (0.4 inches)	67%	extreme
July Weather	24°C (76°F)	2 mm (0.1 inches)	69%	extreme
August Weather	26°C (78°F)	2 mm (0.1 inches)	68%	very high
September Weather	23°C (74°F)	22 mm (0.8 inches)	71%	very high
October Weather	19°C (67°F)	38 mm (1.5 inches)	75%	high
November Weather	14°C (57°F)	48 mm (1.9 inches)	78%	moderate
December Weather	11°C (53°F)	40 mm (1.6 inches)	81%	moderate