There's always the Sun.
Considered one of the warmest countries in Europe, Portugal is known for its mild weather. Although Portugal is bordered on the west and south by the Atlantic Ocean, and by Spain, the country still experiences a Mediterranean climate in most of its regions. However, the temperature can still vary a bit throughout its regions, which includes over 1,000 miles of coastline as well as several interior locations with extreme summer heat. In winters, some areas may experience light snow at times, but it’s not a regular occurrence.
Lisbon, the capital, is located not exactly on the Atlantic coast, but in a sheltered bay on the estuary of the Tagus river, so in summer it is warm (while for example, at Cabo da Roca, it is cool even in summer). Here are the average temperatures.
The sun in central and southern Portugal shines regularly in summer, but even in winter there are several sunny periods, as we can see from the data of Lisbon. In the north, the sun shines a little less often in Porto, on average, about an hour less in both winter and summer.
In Lisbon, the sea temperature is slightly warmer than in Porto, although it's still very cool for swimming, in fact, it only reaches 20.5 °C (69 °F) in July and August.
In inland south-central areas (Alentejo region, see Évora, Beja), summer is definitely hot, especially during heat waves from Africa.
Here are the average temperatures of Beja, where the temperature can reach 45 °C (113 °F) in the worst moments.
In August 2003, in Amareleja, a town located in Alentejo, north-east of Beja, the temperature reached 47.3 °C (117 °F).
In the far south, in Algarve, along the south-facing Atlantic coast, in cities such as Lagos, Portimão, Albufeira, Faro, and Tavira, the climate is Mediterranean, though the summer is not as sultry as in the real Mediterranean areas. The climate here is similar to that of Lisbon but a little less rainy, in fact, the yearly rainfall is around 500 mm (20 in). Summer is sunny, and there are often lively breezes; in addition, there may be some days a bit cool, with highs below 25 °C (77 °F), especially in June and in the first half of July.
However, the cold records in the Algarve are around 0 °C (32 °F), while the heat records are around 40 °C (104 °F).
Here are the average temperatures of Faro.
The sea on the south coast of Algarve is cool, although a little less than in the rest of Portugal, in fact, it reaches 21 °C (70 °F) in August and September. Here is the average sea temperature in Albufeira.
On the south-western tip, in Cape St. Vincent and in Sagres, the summer is cooler: average highs in July and August are only around 25/25.5 °C (77/78 °F). Here are the average temperatures in Sagres.
Lisbon
Average temperature charts in three major Portuguese cities, located in distinct parts of the country.
For more detailed location of these points, please consult a map of Portugal.
Winter, from December to February, is mild on the coast, even in the northern part, since the average temperature in January is around 10 °C (50 °F) in Porto, 12 °C (53.5 °F) in Lisbon, and 12.5 °C (54.5 °F) in Faro.
In winter, there are periods of good weather when the Azores Anticyclone settles in the country, but there are also waves of bad weather, with rain and wind. Sometimes, gale force winds may blow from the ocean, especially in the north.
The position of the country, overlooking the ocean, provides good shelter from cold winds and night frosts, which, in fact, are very rare and not intense, especially on the coast, where the records are a few degrees below freezing in the north and around 0 °C (32 °F) in the south.
On the other hand, in the inland areas of the center-north, the cold is more intense, especially in hilly and mountainous areas, where it can sometimes even snow.
Summer, from June to mid-September, is sunny, and it's mild or even cool on the northern coast, and warm in the center and south. In Porto, the daily average temperatures in August is 20 °C (68 °F), with highs around 25 °C (77 °F). In Lisbon, the average is higher, and reaches 23.5 °C (74.5 °F), with highs around 28 °C (82 °F). However, in the coastal areas most exposed to ocean winds (see Peniche, Sines, Sagres), it is cool even in summer. The Algarve coast is more sheltered, and therefore the temperatures are similar to those of Lisbon.
The heat is more intense in the interior, especially in the south-central, in the plains and in valleys at low altitudes (see Évora, Beja), where sometimes it can be scorching.
However, from mid-June to early September, the whole of Portugal can be hit by heat waves from Africa. In these situations, the temperature can exceed 36/37 °C (97/99 °F) on the coasts, while it can exceed 40 °C (104 °F) in inland areas.
Spring and autumn are cool in the north and mild in the south. The rains are quite frequent, especially in the north, where it can sometimes be a bit cold. In the inland areas of the north, east of Aveiro and Oporto, the winter is colder, not only for the greater distance to the sea, but also because the altitude increases, and at times it can snow.
Further south, and north-east of Coimbra, we find a mountain range, the Serra da Estrela, which reaches 1,993 meters (6,539 ft). Here the temperature can drop to -15/-20 °C (-4/5 °F).
To the north-east of the Serra da Estrela we find Manteigas, at almost 800 meters (2,600 feet), and Guarda, which is located at 1,000 meters (3,300 feet) above sea level.
Further south, and north-east of Coimbra, we find a mountain range, the Serra da Estrela, which reaches 1,993 meters (6,539 ft). Here the temperature can drop to -15/-20 °C (-4/5 °F).
In central and southern Portugal, winter is milder, Atlantic disturbances pass less often over the region, and windy days are less frequent. Summer is warmer, but not on the coast, where the ocean air is felt even in this season.