nomadseason

May Weather in Porto, Spain

Last updated: August 27, 2025

In May, the average temperature in Porto, Spain hovers around 12°C (54°F). Expect a range of temperatures, with a chilly minimum of -1°C (31°F) and a warm maximum of 27°C (81°F). This month brings about 100 mm (4.0 in) of precipitation over approximately 13 days, accompanied by a high humidity level of 84%.

May Temperature in Porto

In May in Porto, the average temperature is 12°C (54°F). The maximum can reach 27°C (81°F), while the minimum can drop as low as -1°C (31°F). This variation in temperatures makes Porto a versatile destination for travelers, offering both warm and cool experiences throughout the month.

May Weather in Porto: Daily Temperature Highs, Lows, and Averages

The chart illustrates May temperature patterns in Porto, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Porto, May typically has an average temperature of 12°C (54°F), with highs reaching up to 27°C (81°F) and lows dropping to around -1°C (31°F).
JanFebMarAprMayJunJulAugSepOctNovDec384143475459646459524341
Data source: Temperature data for Porto generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

May Precipitation in Porto

In Porto in May, the precipitation amount is 100 mm (4.0 in) over the course of 13 days.

May Precipitation Trends in Porto

The chart displays monthly precipitation patterns in Porto, with values for each month alongside May’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how May’s conditions compare to those of other months. In Porto, May typically receives around 100 mm (4.0 inches) of precipitation spread over approximately 13 days.
JanFebMarAprMayJunJulAugSepOctNovDec811231351201009449347199142182
Data source: Precipitation data for May generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

May Humidity in Porto

In Porto in May, humidity is 84%. With an average temperature of 12°C (54°F), this humidity feels like a damp blanket enveloping you, making travel uncomfortable and sticky.

May Average Humidity in Porto

This chart illustrates the average monthly humidity levels in Porto, with May’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In May, average humidity in Porto is approximately 84%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec87%85%83%83%84%84%86%78%77%82%86%87%
Data source: Humidity data for May generated using information from the Copernicus Climate Change Service.

May UV Index in Porto

In Porto in May, 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 Porto.

Maximum UV Index Levels in Porto for May

The chart shows the monthly maximum UV Index (UVI) for Porto in May, 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 May, the maximum UV index in Porto typically reaches 9, which falls under the very high exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec24689111098632
Data source: Porto May 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 May Weather in Porto Compares to Other Months

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

This table compares monthly weather conditions in Porto, showing how May’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
 TemperaturePrecipitationHumidityUV
January Weather3°C (38°F)80 mm (3.2 inches)87%low
February Weather5°C (41°F)123 mm (4.8 inches)85%moderate
March Weather6°C (43°F)135 mm (5.3 inches)83%high
April Weather9°C (48°F)120 mm (4.7 inches)83%very high
May Weather12°C (54°F)100 mm (4.0 inches)84%very high
June Weather15°C (59°F)94 mm (3.7 inches)84%extreme
July Weather18°C (64°F)49 mm (1.9 inches)86%very high
August Weather18°C (64°F)34 mm (1.3 inches)78%very high
September Weather15°C (59°F)71 mm (2.8 inches)77%very high
October Weather11°C (53°F)99 mm (3.9 inches)82%high
November Weather6°C (43°F)142 mm (5.6 inches)86%moderate
December Weather5°C (41°F)182 mm (7.2 inches)87%low

Compare Porto's Climate with Cities Worldwide