The monster wave generated by part of a mountain collapsing into the sea would be the biggest ever recorded and would be an unstoppable force, travelling at speeds of up to 500mph.
The massive wall of water would likely make first landfall on the West Saharan coast of Morocco, where the wave could measure as much as 330ft from trough to crest.
The greatest destruction was nevertheless expected in the built-up coastal areas of the Caribbean, Florida and Brazil, according to a new forecast by Dr Simon Day of the Benfield Greig Hazard Research Centre at University College London.
The tsunami could reach heights of 130ft to 164ft throughout the region and travel several miles inland, leaving a trail of destruction in its wake.
Earlier research by Dr Day had predicted that a future eruption of the Cumbre Vieja volcano in the Canary Islands was likely to cause the western flank of the mountain to slide into the sea.
Dr Day, working in conjunction with Dr Steven Ward of the University of California, has now produced an updated model that predicts more accurately the size of the tsunami and the areas it will impact.
The model predicts that after the landslide the tsunami would travel a distance of almost 155 miles in just 10 minutes and would reach the Caribbean and Florida in eight or nine hours.
The forecast goes on to predict that a wall of water 164ft high could smash into the coasts of the Caribbean and Florida, while Brazil’s northern coast could be hit by a wave more than 130ft high.
According to Dr Day: “The collapse will occur during some future eruption after days or weeks of precursory deformation and earthquakes.
“An effective earthquake monitoring system could provide advanced warning of a likely collapse and allow early emergency management organisations a valuable window of time in which to plan and respond.
“Eruptions of Cumbre Vieja occur at intervals of decades to a century or so and there may be a number of eruptions before its collapse. Although the year-to-year probability of a collapse is therefore low, the resulting tsunami would be a major disaster with indirect effects around the world.
“Cumbre Vieja needs to be monitored closely for any signs of impending volcanic activity and for the deformation that would precede collapse.”