Seixal Temperature by Month

Seixal, Lisbon Region, Portugal has an average annual maximum temperature of 21°C (70°F), ranging from 16°C (61°F) in January to 27°C (81°F) in August. Below you'll find a full monthly breakdown and a comparison with cities worldwide.

Visitors to Seixal will encounter a climate influenced by big temperature differences across the year. Nighttime temperatures range from 18°C (64°F) in August to 10°C (50°F) in January.

The chart below illustrates the average maximum day and minimum night temperatures in Seixal 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 350 hours of sunshine.

The chart below shows the average temperature throughout the year:

Seixal's average annual maximum temperature is 21°C (70°F). To put that in context, here's how it compares to a few well-known destinations:

Rome, Italy averages 20°C (68°F) annually, with reliably warm summers and comfortable winters.

Reykjavík, Iceland averages 9°C (48°F) a year, mild summers by Icelandic standards, but cold winters and frequent wind.

New York City, USA averages 17°C (63°F) a year, with hot humid summers and cold winters that bring regular snowfall.

Melbourne, Australia averages 20°C (68°F) annually, known for unpredictable weather, with four seasons sometimes happening in one day.

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.

Whether a city sits on the coast or deep inland makes a significant difference to its climate. Coastal areas tend to have more stable temperatures year-round, large bodies of water absorb heat slowly in summer and release it gradually in winter, keeping extremes in check. Cities far from the sea don't benefit from that buffer, which is why continental climates tend to have hotter summers and colder winters than their coastal counterparts at the same latitude.

For more on Seixal's weather, including monthly rainfall, sunshine hours, and humidity, visit our Seixal climate page.