Santiago do Cacém Temperature by Month

The average annual maximum temperature in Santiago do Cacém, Alentejo, Portugal is 22°C (72°F), with daytime highs ranging from 16°C (61°F) in January to 28°C (82°F) in August. This page covers monthly averages, day-night differences, and how Santiago do Cacém compares to cities worldwide.

The weather in Santiago do Cacém experiences significant differences between warm and cold seasons, with big shifts in temperature. At night, minimum temperatures range from 17°C (63°F) in August to 8°C (46°F) in January.

The chart below illustrates the average maximum day and minimum night temperatures in Santiago do Cacém by month:

Daily lows are most common between 4 AM and 6 AM. By 3 PM temperatures reach their daily high, driven by peak solar heating. August, the warmest month of the year, receives 340 hours of sunshine.

The chart below shows the average temperature throughout the year:

Santiago do Cacém's average annual maximum temperature is 22°C (72°F). To put that in context, here's how it compares to a few well-known destinations:

Lisbon, Portugal averages 21°C (70°F) annually, warm summers, mild winters, and rain mainly in the cooler months.

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

San Francisco, USA averages 19°C (66°F) annually, but with little seasonal variation, summers are often cool and foggy, winters mild.

Brisbane, Australia averages 26°C (79°F) a year, with warm winters and hot, humid summers.

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 Santiago do Cacém, January is the coolest month, with average highs of 16°C (61°F) and humidity around 81%, considered very high. In August, the warmest month, temperatures average 28°C (82°F) with 50% humidity, conditions that feel moderate. 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.

Global average temperatures have risen by around 1.2°C since the pre-industrial era, and the effects are visible across many regions. Winters are milder on average, with fewer frost days and less snow in many parts of the world. Heatwaves are more frequent and more intense, and Europe's summers of 2018, 2019, and 2020 all set records.

Summers are also getting drier in some areas, while winter rainfall has increased in others. This contributies to higher river levels and more flooding. In many countries, spring arrives earlier and autumn lasts longer. It has knock-on effects for wildlife, agriculture, and local ecosystems.

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