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Rome hits highest temperature on record as heat wave sweeps Europe

Temperatures were 15 to 35 degrees above normal over much of Eastern Europe, the Mediterranean and North Africa

A man cools off at the Barcaccia fountain in Rome on June 27 amid a heat wave in Italy. (Guglielmo Mangiapane/Reuters)

Scorching temperatures have again swept across parts of Europe, with many locations in Italy among those setting June or all-time records for heat.

Temperatures surpassed 104 degrees Fahrenheit (40 Celsius) across much of Italy this week. On Tuesday, downtown Rome hit its warmest temperature on record at 105 degrees Fahrenheit (40.8 Celsius), while several other cities set monthly records. Record-warm temperatures persisted overnight across a large chunk of Eastern Europe. The heat comes during one of the country’s worst droughts in decades and as authorities are rationing water.

The record temperatures are spawned from desert air traveling from the African continent, which has brought excessive heat from Algeria to the Arctic Circle. Slovenia and Croatia both claimed new national heat records. Several other countries, including Finland and Iran, also have experienced new monthly temperature highs.

The heat wave is the latest in a series of extraordinary heat events in the region this year and one of several tormenting the Northern Hemisphere at present — a sign of human-caused climate change. Rising global temperatures have increased the frequency and intensity of heat extremes in these regions since the 1950s, according to the United Nations Intergovernmental Panel on Climate Change (IPCC).

The cause

A dip in the jet stream — an upper-level channel of air — has allowed intense heat to build farther northward than usual.

A powerful heat dome anchored over Eastern Europe is conspiring with low pressure over Western Europe to yank extreme heat off Africa and into the region. A zone of surface high pressure from Italy to northwestern Russia and Finland is squashing clouds, allowing the near-solstice sun to beat down in all its fury.

On the edge of the heat, severe weather struck the Netherlands and Germany.

One person died and 10 were injured as a twister tore through the coastal city of Zierikzee, to the southwest of Rotterdam, in the Netherlands. The tornado caused damage on par with a low-end twister in the United States. Although the Netherlands averages several tornadoes a year, this was the first to cause a death since 1992.

To the south and east of there, numerous reports of hail — some up to 3 inches wide — came in from Germany. Additional severe weather was anticipated across northern Italy and surrounding areas late Thursday as a cold front sinks into the area.

Records fall around Europe

Record-high temperatures were registered from Tunisia to northern Norway on Monday and Tuesday.

Much of the heat centered over Italy, which experienced numerous records:

  • Downtown Rome hit its highest reliable temperature recorded on Tuesday at 105 degrees (40.8 C)
  • Viterbo set an all-time high on Monday at 105 degrees (40.3 C)
  • Campobasso set a June record on Tuesday at 99.3 degrees (37.4 C)
  • Ronchi dei Legionari set a June record on Tuesday at 98 degrees (36.7 C)
  • Tuscany set a June record on Monday at 107 degrees (41.8 C)
  • Florence set a June record on Monday at 106 degrees (41 C)
  • Naples set a June record on Monday at 100 degrees (37.5 C)

The heat coincides with the country’s worst drought in 70 years. Drought has hit the northern region of the country, where a dried-up Po River is affecting farming, hydroelectric power and drinking water supplies. Milan recently announced that it would turn off all its fountains, among other water-saving measures, because of the record drought. It is among more than 100 towns and cities there to enact water restrictions.

Drought and extreme heat events in the Mediterranean have been stronger in recent decades, which has been attributed to an increase in global temperatures. Surface temperature in the Mediterranean is about 2.7 degrees (1.5 Celsius) above the preindustrial number, corresponding to an increase in high-temperature extreme events.

A study released Tuesday found that the Mediterranean and northern Africa are expected to see large increases in the frequency of drought days. By 2065, drought days could make up more than 50 percent of the dry season in those regions if greenhouse gas emissions are not significantly curbed.

Extreme weather tormenting the planet will worsen because of global warming, U.N. panel finds

While the heart of the sweltering weather was arguably in and around Italy, temperatures 15 to 35 degrees (10 to 20 Celsius) above normal covered much of Eastern Europe, the Mediterranean and back into North Africa.

On the northern edge of the heat wave, Scandinavia hit record highs. Porvoo Kalbadagrund, about 30 miles northeast of Helsinki, never fell below 73 degrees (22.7 Celsius), which would be a June record for the country.

Locations on Norway’s Arctic coast of the Barents and Norwegian seas — like Andoya and Berlavag — have broken June and, in some cases, all-time records, with highs in an 85-to-90-degree (29-32 Celsius) zone.

Other notable heat records are:

  • Norway’s largest port city, Tromso, which sits north of the Arctic Circle, reached at least 85 degrees (29.7 Celsius) on Tuesday, a record for June.
  • Mehamm, Norway, located at the top of the Arctic Norway at 71°North, hit 87.4 degrees (30.8 C), shattering its previous June record by almost 10 degrees.
  • Saltdal, Norway set a June record on Monday at 89 degrees (31.6 C).
  • Vihti Maasoja, Finland set a June record on Monday at 89 degrees (31.4 C).
  • Podnanos, Slovenia set a June record on Tuesday at 86 degrees (30 C).
  • Knin, Croatia set a June record on Tuesday at 104.7 degrees (40.4 C).

Readings also approached 121 degrees (50 Celsius) in Tunisia, only a short distance from June records.

One of several big heat waves globally

A wavy jet stream has helped contribute to significant heat waves in several parts of the Northern Hemisphere. In between the dips of the jet stream, relatively stable bubbles of hot air are able to bake the landscape.

Japan remains in the midst of an unprecedented June heat wave.

“A total of 263 June record highs have been set in six days,” meteorologist Sayaka Mori wrote. “Tokyo had highs of over [95 degrees (35 Celsius)] for four days in a row, making it the first time on record for June.”

It’s possible that even hotter weather is on the way for Japan. There is some potential for the hottest day on record in the country experiencing its hottest day on record in the during coming days.

Japan tops 104 degrees for first time in June amid record heat wave

Temperatures in recent days have also risen to record-high levels in parts of Central Asia and into China, as well. Uchadzhi, Turkmenistan observed the hottest June day on record in Central Asia at 118 degrees (48.2 C).

Iran experienced some of its hottest June days on record this week. Khor, Iran experienced its hottest day on record of any month at 118 degrees (47.8 C). Several major cities, such as Tehran, Esfahan and Mashhad, set new June records.

Another sphere of extreme heat has been blasting the Pacific Northwest and adjacent southeastern Canada, as well as parts of Alaska, including its northernmost city of Utqiagvik.

The temperatures are also on the heels of historic June heat in Western Europe, particularly Spain, France and Germany. The record heat sparked wildfires in Spain. Italy and surrounding countries were also blasted by a heat wave in May.

The science of heat domes and how climate change make them worse

India and Pakistan also experienced record heat in March and April, which researchers found were 30 times as likely to occur because of climate change.

Research shows climate change is exacerbating weather patterns responsible for these extreme and long-lasting heat events. Global warming also makes generational-type heat waves more common, perhaps occurring as often as every few years in any one spot.