São Martinho do Porto Temperature by Month

The average annual maximum temperature in São Martinho do Porto, Centro Region, Portugal is 20°C (68°F), with daytime highs ranging from 15°C (59°F) in January to 25°C (77°F) in August. This page covers monthly averages, day-night differences, and how São Martinho do Porto compares to cities worldwide.

The weather in São Martinho do Porto changes moderately throughout the year, offering enough variation to appreciate each season. Nights are cooler, with lows ranging from 18°C (64°F) to 9°C (48°F).

The chart below illustrates the average maximum day and minimum night temperatures in São Martinho do Porto by month:

The coolest part of the day is typically between 4 AM and 6 AM, while 3 PM is usually the warmest, when solar heating is at its peak. August, the city's warmest month, averages 255 hours of sunshine.

The chart below shows the average temperature throughout the year:

São Martinho do Porto's average annual maximum temperature is 20°C (68°F). To put that in context, here's how it compares to a few well-known destinations:

Seville, Spain averages 23°C (73°F) a year, one of the warmer cities in Western Europe, with long hot summers.

Queenstown, New Zealand averages 10°C (50°F) annually, remember seasons are flipped, so its coldest months fall in June and July.

Chicago, USA averages 15°C (59°F) annually, known for extreme seasonal swings, from bitterly cold winters to warm summers.

Tokyo, Japan averages 21°C (70°F) a year, with hot summers, cool winters, and a well-defined cherry blossom spring.

Temperature alone doesn't tell the whole story, humidity plays a big role in how warm or cold it actually feels. High humidity in summer makes the heat feel more intense, particularly once temperatures climb above 25°C. In winter, the same humidity can make cold air feel sharper than the thermometer suggests.

In São Martinho do Porto, January is the coolest month, with average highs of 15°C (59°F) and humidity around 82%, considered very high. In August, the warmest month, temperatures average 25°C (77°F) with 89% humidity, conditions that feel very high. For a full picture, see our humidity page.

Climate temperature data is typically calculated as a 30-year average. This smooths out year-to-year variability and gives a more reliable picture of what a place is actually like, rather than what happened in any single unusual year.

The readings come from a range of sources, land-based weather stations, ocean buoys, ships, and satellites. That data is collected by weather services around the world, then pooled, quality-checked, and averaged to produce the climate records you see here.

Seasonal temperature shifts influence more than just how warm it feels, they also drive changes in rainfall, cloud cover, and wind patterns throughout the year.

Warmer air holds more moisture, which tends to mean heavier or more frequent rain during the warmer months. When temperatures drop in winter, any precipitation that does fall is more likely to come as snow or sleet, though in São Martinho do Porto this rarely lasts long on the ground.

For more on São Martinho do Porto's weather, including monthly rainfall, sunshine hours, and humidity, visit our São Martinho do Porto climate page.