Europe, US swelter under blistering heat

Dozens of cities across southern Europe were under heat wave warnings Saturday, as officials warn of extreme temperatures persisting over the coming days.

In Italy, at least 16 cities were under "red" alerts for heat, including Rome, Florence and Bologna.

In the southern Italian islands of Sicily and Sardinia, temperatures were set to soar to 48 degrees Celsius (118 degrees Fahrenheit).

That would make it the hottest temperature ever recorded in Europe, according to the European Space Agency, whose satellites monitor land and sea temperatures.

The temperature was expected to hit 40 degrees Celsius in Rome on Monday and perhaps climb higher on Tuesday, smashing the 2017 records of 40.5 degrees Celsius in Italy's capital.

In Greece, the Acropolis was partially closed for a second day, with the national weather service warning that "parts of the country could see highs as much as 44 degrees Celsius on Saturday."

The service said the heat wave warnings would continue into next week.

In Spain, the national meteorological service said temperatures in the eastern Iberian Peninsula and the Balearic Islands would rise to between 40 and 42 degrees Celsius.

US, Japan also face scorching weather

Japan has also been experiencing extreme heat, with temperatures expected to rise to 39 degrees Celsius on Sunday and Monday.

In the US, over 90 million Americans were under extreme heat advisories, watches and warnings.

Experts warned that the heat would get worse this weekend for the states of Nevada, Arizona and California, where temperatures were predicted to soar above 120 Fahrenheit (48.8 degrees Celsius) in some desert locations.

In Las Vegas, Nevada, an intense heat wave was threatening to break the city's all-time record high of 47.2 degrees Celsius this weekend. Phoenix, the capital city of Arizona, was set to record temperatures above 43 degrees Celsius for the 15th straight day.

Meanwhile, a series of blazes erupted across California earlier this week. In Europe, a forest fire on the Spanish island of La Palma on Saturday also forced the evacuation of at least 500 people, authorities said.

With some countries suffering from dangerous heat, others like South Korea and China have reported deadly floods due to unusually heavy rains, leaving several people dead.

Scientists have warned that the frequency and severity of heat waves has increased steadily due to the effects of climate change.