Four major heat waves, dry conditions and strong winds have turned Europe into a tinderbox this summer, fueling the most destructive wildfire season in nearly two decades.

A fourth person died as wildfires blaze on in Spain and parts of Europe worsened by sweltering heat fueled by effects of climate change. Spain's weather agency, Aemet, warned the public on Monday to be "cautious" of the "very high or extreme fire danger" in most of Spain as it reported high 108 degree Fahrenheit temperates on Sunday in Cadiz in the southern tip of Spain only miles to the Strait of Gibraltar.

This year is turning into one of the worst fire seasons in recent memory in Europe. Firefighters are struggling to contain out-of-control wildfires in western Spain and Portugal.