According to meteorological records, only five hurricanes have ever arrived in this part of the Atlantic Ocean.
Portugal placed most of the country under red alert Saturday as Hurricane Leslie, which threatens to be the fiercest storm to hit the country since 1842, approached the coast.
The country's civil protection officials called on people along the coast to stay indoors, saying the most serious conditions were likely to be Saturday night and Sunday morning.
The Spanish authorities, meanwhile, were making their own preparations for the hurricane, which Spanish meteorologists expect to reach their territory early Sunday.
The Portuguese capital Lisbon is bracing for the first effects of the hurricane, with strong winds and rain expected at around 6:00 pm (1700 GMT) on Saturday, said the Portugese meteorological institute.
According to meteorological records, only five hurricanes have ever arrived in this part of the Atlantic Ocean. Hurricane Leslie could turn out to be the fiercest storm to hit Portugal since 1842.
Strong winds from Hurricane Ophelia in Portugal and eastern Spain fed forest fires that killed around 40 people during the heatwave in 2017.
Spain is still recovering recovering from the heavy rains that provoked a mudslide in the Mediterranean island of Majorca that killed 12 people Tuesday.