Portugal is mainly characterized by a warm temperate, mediterranean climate with a distinct wet season in winter. During winter, Portugal experiences a similar temperature pattern to the Spanish coastal towns, i.e. average daytime maxima of about 16°C (61°F). However, the Portuguese resorts are much wetter, with only about 14 dry days on average. On average 5-6 hours of sunshine can be expected per day. A gradual warming-up process takes place during the spring months, daytime average maximum temperatures reaching up to 22°C (72°F) by May. The Atlantic-facing coast remains wetter than the Mediterranean-facing Spanish coast, with about 18 dry days per month. Daily sunshine hours number about 10 on average.

During summer months, Portugal receives refreshing sea breezes, making for very pleasant conditions. Daytime maximum temperatures reach 25°C (78°F), 11 or 12 hours of sunshine can be expected, and there are as many as 29 dry days per month on average. The northern region benefits from the Atlantic cyclones southern and eastern areas are dominated by the subtropical anticyclone that allows temperatures to rise up to 40°C during summer. As in other regions, September and the first part of October form an extension of summer. Daytime average maximum temperatures can still be as high as 26 °C (79 °F), but will have fallen back to about 17 °C (63 °F) by November. Daily sunshine hours fall back from about 9 hours in September to about 5 or 6 hours in November. The end of the autumn has reverted to being a wet period, with about 12-17 dry days on average per month.

Suggested clothing:
Lightweight cottons and linens during summer months; warmer medium-weights and raingear during the winter. Whenever and wherever you go, take a sweater for cool evenings.

Koeppen-Geiger classification:
Portugal is classified as Csb climate; a warm temperate moist forest climate, with wet winters, dry summers and the warmest month above 22°C on average.