European Union rushes firefighters into Greece while Italy hits scorching 46C
Wildfires in Greece are threatening lives and hundreds of homes - ITV News' John Irvine has the latest
Firefighting teams from across the European Union have been rushed into Greece to tackle wildfires that have been raging for three days, while in Italy temperatures reached a roasting 46C.
An intense heatwave has continued to grip swathes of the northern hemisphere, in what the World Meteorological Organisation has labelled "a summer of extremes".
Scientists have put the scorching heat down to a combination of human-caused climate change and a newly formed El Niño.
Outside of Europe, health authorities have sounded alarms in the USA, North America and Asia, urging people to stay hydrated and shelter from the record-breaking heat.
Greece
Temperatures in Greece have broken the 40C barrier, with numbers as high as 44C expected in central and southern parts of the country by the end of the week.
The searing heat, combined with gale-force winds, has been linked to fast-moving wildfires outside the capital of Athens.
Throughout Tuesday night, firefighters battled the blazes, with efforts focused on the areas of Mandra, Loutraki and Rhodes.
Senior international correspondent John Irvine reports from the outskirts of Athens, as firefighters and a farmer battled to save farmland from a power wildfire.
In a round-the-clock battle to preserve forests, industrial facilities, and vacation homes, three firefighting teams have been sent from Poland, Romania and Slovakia and are set to arrive in Greece on Thursday.
Israel has pledged two firefighting aircraft, adding to the four planes from Italy and France already operating outside Athens.
1,200 children were forced to flee from a seaside resort on Tuesday, while evacuation orders were put in place for at least five other coastal towns. Further evacuations were ordered on Wednesday.
Meanwhile, workers at Greece's ancient sites will stop work for four hours a day from Thursday in protest at their heatwave working conditions, their union said.
The strike will include employees at the ancient Acropolis citadel, one of Greece's most popular tourist attractions.
Italy
Italy is expected to break its hottest ever temperature record (48.8C) in the coming days, with the heat being around 10C hotter than the average for this time of year.
Red alerts for high temperatures have been issued for 23 of the country's 27 main cities, with hospitals reported to be experiencing an uptick in patients due to the heatwave.
The heat in Rome eased only slightly on Wednesday after a sweltering 42-43C the day before, while highs in Sicily and Sardinia reached 46C.
Rest of EuropeRed alerts have also been issued for Croatia, Serbia, southern Bosnia and Herzegovina, and Montenegro.
In the former three nations, powerful storms toppled trees, tore roofs off buildings and caused power outages after days of extreme heat.Parts of Spain reached as high as 45C on Wednesday, while authorities in North Macedonia extended a heat alert with predicted temperatures topping 43C.
In Switzerland, some 150 firefighters, police, troops and other emergency teams fought a wildfire on Tuesday that engulfed a mountainside in the southwestern Wallis region, evacuating residents of four villages and hamlets.
And around 400 firefighters, assisted by nine water-dumping aircraft, fought a wildfire that burned for a fourth consecutive day on La Palma in Spain’s Canary Islands.
USA
Phoenix in the US has faced a relentless streak of 19 dangerously hot days where temperatures soared to 43.3C or more.
In the southern city, dog parks have emptied out by the mid-morning and evening concerts and other outdoor events have been cancelled to protect performers and attendees.
Less populous places such as Death Valley and Needles, California; and Casa Grande, Arizona, have experienced longer hot streaks, but none in locations where many people live.
As southwestern USA faces unrelenting heat, other parts are facing extreme rainfall, which scientists say is becoming more frequent due to global warming.
This is because clouds hold more moisture as the temperature rises, resulting in more destructive storms.
In Pennsylvania, rescuers are still searching for two children who were swept away from their family’s car by flash flooding.
Matilda “Mattie” Sheils, two, and her nine-month-old brother, Conrad Sheils, went missing on Saturday evening as the suburbs of Philadelphia were hit by floodwater. Their mother, 32-year-old Katie Seley, was found dead late on Saturday, CNN reports.
North Africa
Last week, Algeria and Morocco recorded some of their highest temperatures, reaching a blazing 48C. As a result, the Moroccan meteorological service issued a red alert for extreme heat for southern parts of the country.
North Africa's heatwave is set to continue. Temperatures have rose to 44C in Tunisia's capital Tunis, while forecasters said temperatures this week could reach the mid to upper 40s and are likely to be higher than those in southern Europe.
China
On Wednesday, China's capital Beijing reached a record-breaking streak of four weeks of highs above 35C.
On Sunday, the Asian country provisionally saw its highest temperature on record, with a roasting 52 degrees in Sanbao.
Across the northern hemisphere, atmospheric conditions are allowing persistent areas of high pressure to become established.
These increase the heat and can last for weeks.
The UK is not covered by the area of high pressure so is unlikely to see the extreme heatwave.
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