Portugal indeed has a great variation in its temperatures throughout the days. Even on the coldest winter night, when the temperature reaches low temperatures, during the following day the sun will bring the warm. It is not difficult to see variations from 2°C (35.6°F) at night to daytime temperatures of 20°C (68°F).

Yes, Portugal can get surprisingly cold at night, especially depending on the region and the season. While famous for its Mediterranean sunshine, Portugal’s climate is heavily influenced by the Atlantic Ocean. In the northern and central interior regions, such as the Serra da Estrela mountains, nighttime temperatures in 2026 regularly drop below freezing (0∘C) during the winter, and snow is common. Even in the popular Algarve region or the capital city of Lisbon, summer nights can feel chilly due to the "Nortada" (northern wind), which brings cool air off the ocean after sunset. It is a common mistake for 2026 tourists to pack only light clothing; even in July, evening temperatures can dip to 15∘C (59∘F), requiring a light jacket or sweater. In winter, older Portuguese stone houses often lack central heating, making the damp, coastal nighttime air feel much colder indoors than the thermometer might suggest.