The climate of Portugal, as everywhere is influenced by its geographical location. Being on the west coast of the Iberian peninsular it is affected by the land mass while at the same time being a coastal country, the weather is also influenced by the sea.
There are two fundamental aspects to the pleasant Portuguese climate: the Atlantic felt more in the North, the continental and the Mediterranean, which dominates the south. Portugal temperatures similar temperatures to Spain though the effect of the climate on the vegetation. The climate, through its effect on vegetation, divides Portugal. Such as in Spain, three sets of influences are involved: Atlantic, continental and Mediterranean. The former predominates overall, putting most of the country into the humid zone of the Iberian Peninsula, but is especially true in the Northwest, where it gives a mild, rainy climate.
The maritime winds certainly influence Portugal, especially through its long 700 km coastline.The humidity diminishes, the interior areas being quite 'fair', with the exception of the Tagus North valley, where the climate is wet and soft.
The Northern region benefits from the Atlantic cyclones, while South and East are dominated by the subtropical anticyclone, that allows portugal temperatures to rise up to 40? C during the Summer.
The climate varies according to the altitude and the highest temperatures in Portugal are more likely in the lower regions of the South.
During winter average daytime maxim is about 16°C (61°F) approximately 5-6 hours of sunshine per day. Spring months gradually warm up with average maximum portugal temperatures reaching up to 22°C (72°F) for approximately 10 hours of sunshine per day. During the summer portugal temperatures around 25°C (78°F) and 11 or 12 hours of sunshine per day.
Spring and fall are definitely the best times of year to visit mainland Portugal. Winter starts in November or December and lasts to February or March. Especially in the north and central regions, including Lisbon, the winter is rainy and chilly. The weather usually stays warm from May to September.
The Algarve is moderate year-round, with extremely hot summers and a lot of sun even in the winter. Midsummer is also extremely hot in Alentejo. An evening breeze cools the temperature down along the coast.
The climate in the Azores is mild year-round.
In Madeira, the climate is mild, more or less constant year-round with high temperatures in the summer. Actually, the island has two different climates. One on the north side, and a different one on the south side. The nearly 2000 m high mountains in the middle stop the rain coming from the north side. That gives a lot of rain in the mountains and on the north side. The south side also gets a lot of rain, but mostly as showers, and primarily in the winter.
On Porto Santo (the other inhabited island of the archipelago of Madeira) the climate is very dry, so it's not the "floating garden" Madeira is.
So, the climate in Portugal is neither too hot nor too cold. It depends on the area and the time of the year that you choose to visit Portugal.