A heat wave engulfing southern Europe this past week is expected to send temperatures close to record highs in some areas, prompting officials in Italy, Greece, Spain and elsewhere to impose measures to protect residents and tourists from the scorching conditions.

The latest round of high temperatures, frequently referred to as Cerberus after the multiheaded dog that guards the underworld in Greek mythology, has sent thermometers soaring above 98 degrees Fahrenheit (nearly 37 degrees Celsius).

And it’s expected to get worse. A new wave is on its way — Greek meteorologists have named it Charon, after the underworld’s ferryman.

Governments are bracing for higher temperatures, issuing alerts to warn residents, in the expectation that things will only get hotter in southern Europe and the Balkans in the coming days, according to meteorology experts.

Though it is difficult to link individual events to climate change, scientists say the heat waves in Europe are increasing in frequency and intensity at a faster rate than practically anywhere else on the planet.

This summer is forecast to be worse than last year’s because of El Niño, a natural weather pattern forming for the first time in four years, which has fostered conditions for rising temperatures.

Here’s what you need to know.

How hot will it get?

In Italy, extreme temperatures are expected to hit 104 degrees in Florence and Rome, with potential alarming peaks of 118 degrees in places like the southern islands of Sardinia and Sicily. On Saturday, over a dozen cities were under red alert heat warnings, including Bologna, Florence and Rome. Health officials advised people in affected areas to avoid direct exposure to the sun from 11 a.m. to 6 p.m.

On Friday, Spain’s public weather monitor warned that temperatures in the eastern Iberian Peninsula and Balearic Islands, including Mallorca, would rise to between 104 and 107 degrees through the first half of next week. Some parts of the country could record even higher heat levels, the State Meteorological Agency said.

In Greece, temperatures in a few places on Saturday had already soared above 100 degrees by noon. The country’s national meteorological service warned that heat wave conditions would persist into next week.

Temperatures were expected to rise across Portugal next week, as well, reaching 104 degrees along the coast in the south and 97 degrees in the central and northern regions, according to the Portuguese Institute for Sea and Atmosphere.

In Croatia, residents in the coastal village of Grebastica were evacuated on Thursday after the hot conditions fed a spreading wildfire. Temperatures on the country’s southern coast are expected to rise to 98 degrees in the coming week.

In southern Serbia, temperatures are expected to hit a high of 100 degrees on Sunday. And Poland’s weather authority warned that heat could prompt a risk of forest fires, with highs in the western part of the country reaching 95 degrees.

How are European countries responding?

The deaths of 61,000 people last year could be attributed to the brutal heat in Europe, according to one recent study, with children and older people especially vulnerable to conditions.

After an especially deadly heat wave in 2003, officials in Europe introduced initiatives like warning systems for extreme heat and public cooling spaces. Local municipalities in some areas have tried methods such as adding reflective paint to pavements or creating more space for water to cool the ground. But experts say the authorities have not done enough to establish longer-term solutions to mitigate the effects of heat waves, including adding more greenery and retrofitting public areas and transportation.

With fears that this year’s heat waves could also prove deadly, officials imposed protective measures this past week advising people to stay indoors where possible and to drink plenty of water.

In Italy, where a worker in the northern part of the country died this past week after collapsing while painting some signs in the heat, officials have issued emergency warnings, provided misting tents in some areas and warned people to stay indoors and remain hydrated.

In Greece, the government has activated emergency measures that include opening public cooling spaces, allowing staff in private companies to work remotely and requiring workers at risk of heat stress to stop from noon to 5 p.m. Greece’s civil protection ministry warned of the high potential for fires in five areas and said that government and regional officials were on alert to help respond if needed.

The intensity of the heat on Friday in Athens — close to 100 degrees — led the authorities to temporarily shut the Acropolis during the hottest hours of the day, and similar measures were in effect on Saturday. In recent days, as visitors to the archaeological site atop a rocky, steep hill struggled with the heat, aid workers handed out water to the tourists.

Aaron Boxerman contributed reporting.