According to the Portuguese Met Office, 6 September was the hottest day of the year on mainland Portugal, with the average high set at 38.6 degrees, while the low was fixed at 19.8 degrees.
A total of 73 percent of Portugal’s weather stations also set their highest ever temperatures, with Lousã in central Portugal climbing to 45 degrees Celsius, while Lisbon saw thermometers reach 41.4 degrees.
Rainfall was also well below seasonal averages.
This comes after both July and August broke weather records.
Figures showed that July was the second hottest on record, and was only beaten by temperatures reached in 1989.
Average maximum temperatures were also the highest ever in July, with highs of 32.19 degrees, almost four degrees above what would normally be expected for the month of July.
June 2016 was also the hottest since records were first taken.
Overall, one in four weather stations on mainland Portugal recorded a temperature of 40 degrees on at least one occasion between the final fortnight of June and the beginning of July.
Despite the heat, national health services say they have not reported a severe increase in the number of people seeking hospitals or health centres, nor has there been a rise in the death rate.
The National Health Board Director reasoned that this could be due to a gradual rise in temperatures, with high-risk groups having the time necessary to acclimatise to the hotter weather.
Portugal has in recent years broken a host of weather records.
December 2015 had been the second warmest December in Portugal since records began in 1931, while the whole of 2015 was the second warmest in the past 15 years, and the fourth driest.
Meanwhile, 2015 also recorded the hottest November in the last 34 years in Portugal, with a heat wave in some parts of the mainland, though the month will be remembered for the flooding across the Algarve which caused severe damage in places like Albufeira.
Average temperatures in Portugal have in the last 40 years increased at a rate of 0.5 degrees per decade - twice as fast as globally - posing major dangers to the country, according to Filipe Duarte Santos, professor at the Faculty of Sciences of Lisbon University who, along with various entities, monitors climate change both nationally and internationally.
He has repeatedly forecast that climate changes in Portugal will be more frequent and will be accompanied by more intense droughts and “extreme precipitation” that will bring with it the risk of flooding and landslides.
“Portugal is more vulnerable to climate changes due to it having a relatively long coast with significant extensions of dunes and estuaries,” he told Lusa News Agency in 2015.
“Small enclosed beaches, which have a great landscape and touristic value, are especially vulnerable to a rise in average sea level.”
A study carried out by researchers from various universities, showed “systematic temperature increases that can reach three to seven degrees centigrade in summer, with stronger heating in the north and central interior and a strong increment in the frequency and intensity of heatwaves” in mainland Portugal.
The study, entitled ‘Portugal’s climate in the 20th and 21st centuries’, was carried out by the SIAM (Scenarios, Impacts and Adaptation Measures) project.