It comes as the heatwave which has hit Ireland and across Europe is expected to continue following more comfortable temperatures this week, with high temperatures expected across the continenent and in parts of the UK.
Spain's highest recorded temperature is 46.9C (116.42F) in Cordoba, a southern city, in July 2017.
Eight places in the centre, south and east of Portugal have broken their local temperature records amid a heatwave, the country's weather agency says.
In what could be the hottest ever weekend on record those living in Spain and Portugal could be set to experience staggering highs of 48C.
Tyler Roys, a meteorologist from website AccuWeather, said it is possible that "between Friday and Sunday temperatures could reach 49 degrees centigrade in south-west Spain and in parts of southern Portugal".
Fires typically flare late in the day when the weather is hottest.
Large areas of Portugal are on red alert for heat, including the capital, Lisbon.
The country's civil protection agency reported 426 firefighters were putting out fires or checking alerts in the north and centre of the country. Highs of 44 degrees Celsius are forecast for most of Spain. While fires are an annual problem in much of Europe, the hot, dry conditions for an extended period of time made those fires much more likely.
Meanwhile in Spain, media reports said two people died of heatstroke in the southeastern Murcia region, while a third - believed to be homeless - died in Barcelona.
On the other hand, the long and hot summer pressed the German breweries, which sold so much beer to the point of causing shortages of bottles, recovering the negative record of sales past year.
People cool off in an urban beach at Madrid Rio park in Madrid, Friday, Aug. 3, 2018.
Finland's August average is 19 degrees Celsius but temperatures approached 30 degrees Celsius this week and few have air-conditioning at home.
He said: "After a fresher weekend we are going to see a return to the hot weather, we expect temperatures back into the low-30Cs by Friday". In Sweden July was a record hot month and wildfires burnt in parts of the country.
114 people were killed in two massive forest blazes past year in Portugal and civil services yesterday sent mobile text alerts warning the population of an extreme risk of fires in some regions, including around the capital Lisbon.