Authorities in Croatia and Turkey have also had to evacuate citizens amid forest fires and scorching temperatures.
A pilot of a firefighting plane died Friday when his plane crashed while on an operation in the northeast, the first in this year's fires in Portugal so far.
Temperatures are above 40 degrees Celsius amid a heatwave in many parts of the country, while around 30,000 hectares of land have been burned.
A major wildfire that started last week in the Ourém municipality, north of Lisbon, was reignited on Tuesday due to strong winds.
The country's Civil Protection Authority said 860 people had been evacuated from several villages and around 160 people -- including at least 70 firefighters -- have needed medical treatment.
In the nearby municipality of Leiria, houses had been burned down, with the blazes causing the closure of three major roads. Many locals have complained there were not enough firefighters and resources to combat the fires.
"We are talking about complex situations, a lot of resources to manage and a very large affected area," said Civil Protection commander Andre Fernandes, warning the situation would only get worse over the next few days.
Around 1,700 firefighters, backed by 500 vehicles, were tackling 14 active blazes across the country, Civil Protection authorities said. Meanwhile, more than half of the country is on "red alert", the highest level.
Temperatures in central Portugal were forecast to hit 44 C on Thursday. In June, 96% of the country was classified as being in either “extreme” or “severe” drought.
High temperatures and strong winds fuel fires across the Mediterranean
The European heat wave is also sparking flames in other Mediterranean countries.
In neighbouring Spain, at least 5,500 hectares have been destroyed by a fire in Las Hurdes in Extremadura, western Spain, this week.
The blaze has forced the evacuation of about 400 residents from eight villages, the regional government said on Thursday.
There was also a high risk of wildfires in the central region of Castille and Leon, authorities said, while the northwestern province of Ourense was on red alert as temperatures were expected to reach 42 C.
Meanwhile, more than 1,000 firefighters have been battling since Tuesday to bring two wildfires under control in southwestern France near Bordeaux.
The blazes have already burnt more than 7,000 hectares of forest and grassland and prompted the evacuation of as many as 11,000 people along the Atlantic coast.
Images shared by firefighters showed flames shooting across a mass of pine trees and black smoke stretching across the horizon.
Firefighters focused efforts on Saturday on using fire trucks to surround villages at risk and save as many homes as possible, Charles Lafourcade, overseeing the French firefighting operation, told reporters at the scene.
Some 3,000 firefighters backed by water-dumping planes are battling the blazes in southern France, the president said, and Greece sent firefighting equipment to help.
On Bastille Day, the Gironde prefecture has forbidden all fireworks until Monday in towns and villages near forests.
High temperatures and strong winds have complicated firefighting efforts, as the blazes ravaged pine forests and destroyed some cars and homes. No victims have so far been reported.
European Union officials issued a warning last week that climate change is responsible for the continent's dry and hot summer, urging local authorities to brace for wildfires.
Fuelled by strong winds, fires have also raged along Croatia’s Adriatic Sea coast as well, with the most dramatic situation reported near the town of Šibenik, where water-dropping planes and dozens of firefighters struggled to contain the flames that briefly engulfed some cars and a church tower.
Two firefighters were killed in Greece when their helicopter crashed in the Aegean Sea on Wednesday near the island of Samos.
In southwestern Turkey, a blaze erupted close to the village of Mesudiye, near the Aegean Sea resort of Datça, and was moving toward homes in the area, according to the provincial governor’s office. It said at least nine water-dropping helicopters and five planes were deployed to battle the fire.
Meanwhile, the UK's Met Office weather agency warned on Friday that record temperatures expected next week pose a risk of “serious illness or danger to life.”