As a dangerous weekslong heat wave in parts of the Western United States only gets worse this weekend, more than 90 million people are under emergency heat alerts.

And in Europe, a deadly heat wave is sweeping the continent, putting locals and tourists alike in danger.

In Italy, the Italian health ministry has issued a ‘red alert heat warning’ and advised tourists to stop sightseeing in Rome.

Several tourists have already succumbed to heat stroke, with one British tourist passing out in front of the ancient Roman Colosseum on Tuesday.