UK heat wave: Extreme heat is exposing a country woefully ...

Americans are used to switching on their air conditioners any time temperatures near 80 degrees Fahrenheit (27 degrees Celsius). But in the UK, record-shredding heat this week has brought life to a pandemic-esque standstill.

Temperatures in the UK breached 40 degrees Celsius (104 Fahrenheit) for the first time on Tuesday, making it the country's hottest day on record.

In the US, one-third of the population was under heat-related weather warnings on Tuesday and Wednesday, with temperatures expected to climb north of 110 degrees Fahrenheit (43 degrees Celsius) in the Plains states.

Looking at the cause of these heat extremes in the US and Europe, there are different systems at play.

In Europe, a strong ridge of high pressure has allowed temperatures to build over the continent for the past several days. On Tuesday, an area of low pressure was moving in off the coast, acting to help funnel the extreme heat northward into the UK.

In the US, a strong dome of high pressure has set up over the Southern Plains and Mississippi Valley. Instead of heat being funneled in from the south, it is building unabated as the sun bakes down through cloudless skies.

The connecting tissue between these heat waves is the influence of greenhouse gas emissions and the planet's ever-warming baseline temperature.

The UK Met Office's chief scientist, Stephen Belcher, was in a state of disbelief as he delivered a video statement about the shocking temperatures the country experienced Tuesday, noting they would have been "virtually impossible" the UK in an "undisrupted climate."

"But climate change driven by greenhouse gases have made these temperatures possible, and we're actually seeing that possibility now," he said, adding that if the world keeps emitting greenhouse gases at the level it is now, such heat waves are likely to occur there every three years.

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Forty degrees Celsius mat not be that hot to someone sitting in the Central US, Australia, the Middle East or in northern India. In the UK, it forced people to work from home and students to study remotely. Authorities told people not to take trains , which become dangerous on hot tracks that expand and bend in the heat.

In other words, don't leave home.

But in the UK, which is more likely to struggle with cold rather than hot, homes too are designed to keep heat in. Desk fans are selling out all over the country, but they only go so far.

The weather has got Brits so hot and bothered, poor heat management has become the latest criticism hurled at the nation's outgoing prime minister Boris Johnson -- this week held up as another example of the disgraced leader's failures.

"The all-time temperature record for the UK has not just been broken, it has been absolutely obliterated," said Hannah Cloke, natural hazards researcher at the University of Reading. "The mark of 39 degrees Celsius will never even exist as a UK temperature record, because we have just soared past it into the 40s in a single sweaty leap."

The UK is woefully unprepared for the impacts of the climate crisis. It struggles to manage floods when they occur. In the heat, the nation buckles.

So many fires ignited in London on Tuesday that the city's fire brigade declare a "major incident" and were stretched beyond their capacity. Four people have drowned as people flocked to beaches, rivers and lakes just to try to get cool. Even a runway at an airport on London's outskirts had to be closed off as it melted in the heat.

In southern Europe, a region more accustomed to extreme heat, at least 1,100 people have died in the latest heat wave, and French firefighters are overwhelmed with blazes tearing through forests. Twenty-one European nations are under heat-related warnings.

Americans may be more used to the heat, but heat waves are getting longer and more frequent there too, which means more time indoors, or wherever the air conditioning may be. No fewer than 100 million Americans -- almost a third of the nation -- were under heat alerts on Tuesday.

The alerts run from the southern Plains into the Mississippi and Tennessee River Valleys, and there are scattered alerts through the Southwest. The Northeast has already issued heat advisories for heat "feeling like" 100 degrees Fahrenheit (37.8 Celsius) for Wednesday.

The most dangerous heat is forecast around parts of Texas, Oklahoma and Arkansas where excessive heat warnings are in place for Dallas, Oklahoma City, Tulsa and Little Rock. Temperatures there are expected to soar to 100 to 110 degrees Farhenheit (as high as 43 degrees Celsius) over the next few days.

Scientists who work on just how much of a role the climate crisis is playing in extreme weather now say that just about every heat wave in the world is influenced by humans burning fossil fuels.

Friederike Otto from the Grantham Institute for Climate Change at Imperial College London said that it was up to the world to reach net zero -- where humans emit as little greenhouse gas as possible and "offsets" the rest -- to stop heat waves from becoming even worse, "deadly and disruptive."

"We have the agency to make us less vulnerable and redesign our cities, homes, schools and hospitals and educate us on how to keep safe," Otto told CNN. "40 degrees Celsius in the UK is not an act of god, but to a large degree due to our past and present burning of fossil fuels."

In China, the annual "sanfu" -- which is usually three lots of 10 days in July and August when temperatures and humidity peak -- is now forecast to run for an "extended period" of 40 days, the state weather forecaster said, according to Reuters

It warned of scorching heat waves this week, despite seasonal rain, with temperatures likely climb as high as 42 degrees Celsius (107.6 Fahrenheit) in the south from Wednesday.

In central London on Tuesday, a student named Asser who braved the heat told CNN that world wasn't doing enough to battle the heat waves.

"In fact, the world is doing nothing. The world is burning and we are doing nothing about it. We are just consuming, the industry is running and nobody is doing anything about the climate" he said.

"You've got heat waves in Europe and London and US, everywhere -- you can see it, it's obvious. You've got floods and wildfires and everything."

Analysis Angela Dewan
International Climate Editor

More than 100 million in the US face excessive warning or heat ...

(CNN) Heat alerts cover more than 20 states today and Wednesday across the Southern Plains and parts of the Northeast, and temperatures will soar above the century mark for 60 million people over the next week. All while a similar heat wave is bringing all-time record temperatures to Western Europe .

"Dangerous heat will continue to impact a large portion of the US this week, with now more than 100 million people under excessive heat warnings or heat advisories," the Weather Prediction Center said

Between today and Wednesday, nearly 40 high temperature records are at risk of breaking. Also, through Thursday morning over 90 warm minimum temperature records could fall. 🌡 For more, visit: https://t.co/jnP5oP2MfY pic.twitter.com/AixMyPaCP0

It means one-third of the US population is under heat advisories and excessive heat warnings, and more than 80% of the US population (around 265 million Americans) will see a high above 90 degrees over the next seven days.

Oranges and red colors show where high temperatures are forecast above 90 degrees Wednesday.

The highest temperatures, pushing well into the triple digits, will be once again centered over the southern Plains.

More than two dozen record highs are possible today and tomorrow for the Southern US, including Texas, Oklahoma, and New Mexico, and the East Coast is about to get into the mix as well.

The entire state of Oklahoma hit 103 degrees today, according to Oklahoma Mesonet, a joint weather updating system with Oklahoma State University and the University of Oklahoma.

"This is the first time in our network's history (dating back to the mid 1990s) to have 120 sites hit that mark on the same day. Before today we had 2 days with all sites hitting 100F or higher (7/9/11 and 7/10/11)," a tweet from the project read.

A number of record highs have been set across Texas and Oklahoma today as the region bakes in extremely high temperatures. Abilene, Texas, and Oklahoma City both broke records set in 1936 -- with both reaching 110 degrees, according to CNN meteorologist Mike Saenz.

Additionally, Wichita Falls, San Angelo and the Midland International Air & Space Port in Texas all broke records set in 2018, Saenz said.

The Electric Reliability Council of Texas set another unofficial record Tuesday for demand, a spokeswoman told CNN.

Another record is expected on Wednesday.

Parts of the Northeast will also have temperatures nearing daily records Wednesday and Thursday.

"Heat advisories are also now in effect for Wednesday for portions of the Northeast, including the I-95 corridor from Philadelphia to Boston, where heat index values are forecast to reach near 100 degrees," the Weather Prediction Center said.

Intense heat disrupts Texas prisons and outdoor events

A pedestrian walks with a bag covering her face to block the sun during a heatwave in Houston, Texas.

After a record-breaking heat day Monday, the southern Plains are being met with dangerous heat once again.

Dallas inched toward its daily record of 110 degrees yesterday but topped out at 109, making it the hottest day of the year so far.

Critical fire danger expected Tuesday as winds increase and hot temps and low humidity continue. Be careful with activities that can start fires! Please do our local fire fighters a favor. They'd rather spend the afternoon with A/C.

#dfwwx #ctxwx pic.twitter.com/7IJ84moiQL — NWS Fort Worth (@NWSFortWorth) July 19, 2022

Even first responders are falling victim to the scorching temperatures. A firefighter in Robertson County, Texas, suffered heat exhaustion on Tuesday -- when temperatures rose to about 112 degrees -- while battling a wildfire that was started by a resident burning trash, according to the Robertson County Emergency Management Facebook page.

The 15-acre fire destroyed one structure before volunteer fire departments stopped its spread, the post read.

And some Texas prison facilities housing inmates do not have working air conditioning, the state Department of Criminal Justice said Tuesday.

"There are 100 TDCJ units, 31 have full AC, 55 have partial AC, and 14 have no AC. We take numerous precautions to lessen the effects of hot temperatures for those incarcerated within our facilities," agency spokesperson Amanda Hernandez told CNN in an email.

The agency says some inmates have fallen ill from heat-related injuries and needed medical care.

"In 2022, there have been seven inmates who required medical care beyond first aid for heat related injuries and none were fatal," Hernandez said, adding the agency has measures in place to keep inmates safe.

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"The department uses an array of measures to keep inmates safe. Everyone has access to ice and water. Fans are strategically placed in facilities to move the air. Inmates have access to a fan and they can access air conditioned respite areas when needed," Hernandez said.

Excessive heat warnings and heat advisories are in effect through Wednesday for North and Central Texas.

"The air temperatures will climb to 105 to 110 degrees in the warning area, with heat index values over 105 degrees in the advisory area," the National Weather Service in Fort Worth said

Southern and Midwest states are feeling the burn, too

As hot temperatures, low humidity, and wind speeds pick up, a critical fire danger threat is also in effect for northern Texas and central Oklahoma.

Oklahoma City could see highs nearing 110 degrees today, which would break their daily record of 109 set back in 1936.

"The last time we had a substantial stretch of heat was in 2011, when we had 63 days greater than or equal to 100 degrees," Vivek Mahale, a Norman National Weather Service meteorologist, said.

Mahale expects the above-average heat to continue into at least Sunday, with every day reaching the triple-digit mark. The Oklahoma City Will Rogers World Airport has seen nine days above 100 degrees this month.

He advised the best thing you can do to prepare is to check on vulnerable populations as temperatures will be five to seven degrees above normal.

"We really want to emphasize you want to check on your friends, family, and neighbors during the heatwave, especially susceptible populations such as the elderly," Mahale said.

About 8,800 customers in western Arkansas -- where temperatures were forecast to reach 106 degrees Fahrenheit -- were without power around noon Tuesday after a windstorm damaged the local electric system.

While the windstorm broke more than 40 electric poles, Paris Mayor Daniel Rogers told CNN, "the problem here is the heat."

Paris High School opened for people "who need a cool place to be after last night's storms," according to a Facebook post, a resource the mayor urged residents to take advantage of.

"Don't try to brave out the heat," the mayor said. "Heat-related illness is a serious matter."

In Louisiana, a funeral will be held Thursday for a Natchitoches Police Department officer who died Saturday evening from "an unexpected heat related medical event while working in the downtown district," the police department announced on Facebook Tuesday. Natchitoches is about 76 miles southeast of Shreveport.

"Please continue to keep his family and all that had the privilege of knowing Officer Brian Olliff in your thoughts and prayers," the post read.

Farther north, Michigan's Occupational Safety and Health Administration encouraged employers to be aware of heat hazards and help prevent heat illness.

"Whether you're working indoors or outdoors, hot and humid conditions can pose serious risks to workers' health, but heat-related illnesses are preventable," Michigan's Occupational Safety and Health Administration Director Bart Pickelman said in a news release

Employers, it said, should have detailed procedures in place for monitoring the heat index, provisioning water and caring for a sick employee, it said.

New York, Boston and Philadelphia brace for sweltering week ahead

Boston, MA - Warm weather brought people out to the Esplanade in Boston in June.

Heat advisories are in effect Wednesday for the Northeast, including New York City, Boston, and Philadelphia.

Heat index values -- the temperature it feels like when heat is combined with humidity -- could top 100 degrees in some areas, generating dangerous conditions for Mid-Atlantic and New England residents.

Hot and humid conditions will combine to produce maximum heat index values ranging from the mid 90s to around 100 on Wednesday and Thursday. A Heat Advisory is in effect across the entire area. https://t.co/6NEWpQSiDp pic.twitter.com/jdnYg3rsLo — NWS New York NY (@NWSNewYorkNY) July 19, 2022

The heat and humidity won't just hug the coast. Upstate New York could also see temperatures well above average.

Albany, New York, is soaring above its average of 84 degrees for this time of year, and the city could near its record of 97 degrees tomorrow with the stifling heat.

To make matters worse, humidity combined with heat will make some areas feel 5-10 degrees hotter.

"This is going to be little bit (warmer) than just the typical hot and humid weather that we get in July," Mike Evans, a meteorologist at the National Weather Service office in Albany, New York, told CNN.

Evans said dew points could push 70 degrees tomorrow, which is when humidity becomes "very noticeable."

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Portions of Massachusetts will reach record levels as soon as Wednesday, as temperatures reach the upper 90s, and will continue through the rest of the week in the Northeast.

"This is going to be the hottest day we've had so far, this summer. We really haven't had too hot of a summer here, at least in the Northeast," Evans said.

Palm Springs ties record for hottest day ever at 123 degrees

The temperature records keep falling across the Coachella Valley and summer hasn’t even arrived.

Palm Springs tied the city's all-time record for the hottest day ever Thursday when the thermometer touched 123 degrees between 3 and 4 p.m.

For a time, it appeared the thermometer at Palm Springs International Airport may have touched 124 degrees for the warmest day ever, but the weather service confirmed that 123 degrees was the official high.

"Basically, those observations are taken in Celsius and sometimes when it converts to Fahrenheit, there can be a little discrepancy," said Liz Schenk, a meteorologist with the National Weather Service in San Diego.

"It can be a little wonky when you go back and forth between the two metrics so that's why we wait to dial into the observation readings on our system."

Thursday marked the fourth day in 128 years of weather records where Palm Springs reached 123 degrees. The other three occasions were on consecutive days of July 28 and July 29 in 1995 and the first time was Aug. 1, 1993.

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The 123-degree reading will go down as the hottest June day ever, surpassing the old record of 122 degrees set on five previous days in the month.

Schenk said the weather service was keeping a close eye on the Palm Springs temperature Thursday afternoon as the city threatened its all-time high.

"We were watching closely," she said. "Even tying an all-time record is pretty cool.

"When you are dealing not only with a daily record but an all-time record, we have to check a bunch of things to make sure it is accurate," she said.

More:Doctors warn of burns from asphalt as heatwave hits Southwest

Thursday marked the second high temperature record for the week in Palm Springs. The city easily eclipsed the old record for the date of 116 degrees set in 1961.

“It’s pretty rare to hit 122 and that’s over almost 100 years of records,” said Ivory Small, a meteorologist with the weather service. “Six days is too many.”

Palm Springs was not alone across Southern California in setting record high temperatures on Thursday as a scorching heat wave continued. Thermal also broke its daily record by touching 118 degrees. The old mark of 114 was set in 2008. Thermal's all-time record is 126 degrees, Schenk said.

“This high pressure is broader and more locked over the West than most are,” Small said.

The Coachella Valley may not be done with records quite yet. The weather service forecasts a high of 116 on Friday, which is one degree shy of the record of 117 for the date. Saturday’s forecasted high of 117 is two degrees shy of the record of 119.

For Father’s Day on Sunday, the record high is 122, but the weather service only predicts a high of 115.

“It will be so cool you won’t even need your air conditioner,” joked Small, “since it won’t even be 120.”

China's summer of extreme heat and rainfall highlights threats of ...

A version of this story appeared in CNN's Meanwhile in China newsletter, a three-times-a-week update exploring what you need to know about the country's rise and how it impacts the world. Sign up here.

Hong Kong (CNN) Towns and farmlands inundated by floods, homes and roads buried by landslides, crops withering under scorching heat, hazmat-suited Covid workers collapsing from heatstroke.

Since summer began, scenes of devastation and misery have been playing out across China as the world's most populous nation grapples with an unrelenting torrent of extreme weather emergencies.

Scientists have been warning for years that the climate crisis would amplify extreme weather, making it deadlier and more frequent. Now, like much of the world, China is reeling from its impact.

Since the country's rainy season started in May, heavy rainstorms have brought severe flooding and landslides to large swathes of southern China, killing dozens of people, displacing millions and causing economic losses running into billions of yuan.

In June, extreme rainfall broke "historical records" in coastal Fujian province, and parts of Guangdong and Guangxi provinces. At the same time, a heat wave began to envelop northern China, pushing temperatures over 40 degrees Celsius (104 Fahrenheit).

In recent weeks, a total of 71 national weather stations across China have logged temperatures that smashed records. Four cities -- three in the central province of Hebei and one in Yunnan in the southwest -- saw temperatures reaching 44 degrees Celsius (111 Fahrenheit), according to the National Climate Center.

People queue at a Covid testing site in Beijing on June 13.

The stifling heat has coincided with a surge in Covid cases, making government mandated mass testing all the more excruciating for residents -- including the elderly -- who must wait in long lines under the sun. It has also become a dangerous task for health workers who, as part of the government's zero-Covid policy, are required to spend long hours outdoors covered head to toe in airtight PPE equipment as they administer the tests.

Several videos of Covid workers collapsing on the ground from heatstroke have gone viral on social media.

The heat wave has also caused power shortages in some regions and hit the country's crop production, threatening to further push up food prices.

And the worst might be still to come, according to Yao Wenguang, a Ministry of Water Resources official overseeing flood and drought prevention.

"It is predicted that from July to August, there will be more extreme weather events in China, and regional flood conditions and drought conditions will be heavier than usual," Yao told state-run Xinhua news agency last month.

Counting the costs

China is a "sensitive area" that has been significantly affected by climate change, with temperatures rising faster than the global average, according to the country's latest Blue Book on Climate Change , published by the China Meteorological Administration last August.

Between 1951 and 2020, China's annual average surface temperature was rising at a pace of 0.26 degrees Celsius per decade, the report said. Sea levels around China's coastlines rose faster than the global average from 1980 to 2020, according to the report.

The changing climate can make extreme weather events -- such as summer floods, which China has grappled with for centuries -- more frequent and intense, said Johnny Chan, an emeritus professor of atmospheric science at the City University of Hong Kong.

A warmer atmosphere can hold more water vapor, potentially leading to heavier rainstorms, while global warming can alter atmospheric circulation, which can contribute to extreme weather such as heat waves, Chan said.

"We should be really concerned, because these extreme weather events actually affect the most underprivileged, disadvantaged and vulnerable parts of the population -- those in the rural areas, or those who don't have air conditioning or live in very crowded conditions," Chan said.

Residents spend their time in an air-raid shelter to escape summer heat amid a heat wave warning in Nanjing, Jiangsu province on July 12.

For China, the sheer size of its population and economy means the scale of damage caused by extreme weather events is often massive.

Tropical cyclones, floods and droughts are estimated to cost China about $238 billion annually -- the highest in the Asia Pacific region and nearly three times the estimated loss suffered by India or Japan, according to a report released last year by the World Meteorological Organization.

Heat wave-related mortality in China rose by a factor of four from 1990 to 2019, reaching 26,800 deaths in 2019, according to a Lancet study published in 2020.

New reality

Meanwhile, many Chinese are only just beginning to realize that climate change will affect them personally.

In 2019, researchers found that compared to other countries, public concerns over global warming and climate change in China were "relatively low."

The Chinese government has promised to bring greenhouse gases to a peak before 2030 and to achieve carbon neutrality by 2060.

For many Chinese, the dangers of extreme weather fueled by climate change hit home last summer, when devastating floods killed 380 people in the central city of Zhengzhou, the provincial capital of Henan province.

Rescuers help evacuate stranded residents at the entry to an expressway in flood-hit Zhengzhou, central China's Henan Province on July 23, 2021.

Last July, the city of 12 million was pelted with what its water station called a "once in a thousand years" downpour, but local authorities were ill-prepared and failed to heed the five consecutive red alerts for torrential rain -- which should have prompted authorities to halt gatherings and suspend classes and businesses. Flood water gushed into the tunnels of the city's subway system , trapping hundreds of passengers and killing 12 of them in a tragedy that gripped the nation.

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Liu Junyan, climate and energy project leader for Greenpeace East Asia, said the Zhengzhou flooding was a wake-up call for the Chinese government and public.

"The central government and local governments started to be aware that climate change is such an enormous threat to society and its sustainable development," she said, adding that she has noticed more discussions about climate change and extreme weather in China's traditional and social media.

Since last summer, many Chinese cities have improved their emergency response systems for extreme rainfall. In May, authorities in the southern metropolis of Guangzhou suspended schools, advised residents to work from home, closed construction sites and suspended public transportation in parts of the city following alerts for torrential rains.

This June, the Chinese government released a new policy document to improve its response to climate change, which it said was not only creating long-term challenges but also made the country more vulnerable to "sudden and extreme" events.

"Climate change has already brought serious adverse impacts to China's natural ecological system, and has continued to spread and penetrate into economy and society," the government said in its national climate change adaptation strategy.

It vowed to make China a "climate-resilient society" by 2035, by building a nationwide system to monitor and assess climate risks, and by boosting early warning capabilities.

Liu said the policy document is a "very big and ambitious" piece of guidance for local governments, but it lacks details on implementation.

"The impact of climate change can be very localized and its threat to vulnerable communities can be very different from place to place," she said. "Local governments still need to develop more detailed and tangible plans to implement this grand strategy."

Europe is burning as heat moves east while US and China ...

London (CNN) Hundreds of millions of people around the world were sweltering in extreme heat on Wednesday, as record-breaking heat waves set swathes of Europe's countryside on fire, scorched the US and put dozens of Chinese cities under alert.

Five separate high-pressure weather systems across the northern hemisphere, which are linked by atmospheric waves, have led to unprecedented temperatures on multiple continents. The UK smashed its all-time heat mark on Tuesday, as did several cities in the Texas and Oklahoma, including Wichita Falls, which reached a broiling 115 degrees Fahrenheit (46.1 degrees Celsius) on Tuesday.

Residents of Alhaurín el Grande, Spain, were evacuated due to a fire in the Sierra de Mijas mountain range on July 15.

Residents of Alhaurín el Grande, Spain, were evacuated due to a fire in the Sierra de Mijas mountain range on July 15.

Residents watch as a column of smoke emerges from a fire in A Pobra do Brollón, Spain, on July 17.

Residents watch as a column of smoke emerges from a fire in A Pobra do Brollón, Spain, on July 17.

Firefighters set a backfire to a plot of land to prevent a wildfire from spreading further in Louchats, France, on July 17.

Firefighters set a backfire to a plot of land to prevent a wildfire from spreading further in Louchats, France, on July 17.

People look at plumes of smoke caused by a wildfire in Malaga, Spain, on July 15.

People look at plumes of smoke caused by a wildfire in Malaga, Spain, on July 15.

People rest after being evacuated from a campsite in western France on July 13.

People rest after being evacuated from a campsite in western France on July 13.

A firefighter looks on during firefighting operations in Espite, Portugal, on July 13.

A firefighter looks on during firefighting operations in Espite, Portugal, on July 13.

A cloud of smoke rises from the Dune of Pilat, in the Arcachon basin of southwest France, on July 13.

A cloud of smoke rises from the Dune of Pilat, in the Arcachon basin of southwest France, on July 13.

A local resident tries to stop flames from reaching houses in Figueiras, Portugal, on July 12.

A local resident tries to stop flames from reaching houses in Figueiras, Portugal, on July 12.

Firefighters attempt to control a fire in the French communes of Landiras and Guillos on July 13.

Firefighters attempt to control a fire in the French communes of Landiras and Guillos on July 13.

Burnt cars and trees are seen at a campsite in southwest France on July 19.

Burnt cars and trees are seen at a campsite in southwest France on July 19.

An aerial view shows the rubble and destruction in a residential area following a large blaze the previous day, in Wennington, Greater London, on July 20.

An aerial view shows the rubble and destruction in a residential area following a large blaze the previous day, in Wennington, Greater London, on July 20.

An aerial view shows burnt olive trees and fields in Megara, west of Athens, on July 20.

An aerial view shows burnt olive trees and fields in Megara, west of Athens, on July 20.

A firefighter battles a blaze in the suburb of Pallini, east of Athens, Greece, on July 20.

A firefighter battles a blaze in the suburb of Pallini, east of Athens, Greece, on July 20.

As Europe's heat wave moves eastwards, wildfires have forced tens of thousands of people from their homes, blanketing parts of Italy, Greece and France in smoke. Germany recorded its hottest day of the year as temperatures reached 104.5 F (40.3C) at a measuring station in Bad Mergentheim-Neunkirchen, in the center of the country, while Hungary and Italy have been hit with high temperatures of around 100 F (nearly 38C) in places.

The European Forest Fire Information System put 19 European countries on "extreme danger" alerts for wildfires on Wednesday, across an expanse stretching from Portugal and Spain in the southwest to Albania and Turkey in the southeast.

There was some respite in the UK, where temperatures dipped from an all-time high of 40.3 C (104.5 F) on Tuesday back into the 20s. But some residential areas around London were left in ruins after fires broke out across parts of the capital, stretching the fire service to its limits.

"Yesterday was the busiest day for the fire service in London since the Second World War," London's mayor Sadiq Khan told Sky News on Wednesday, as residents of the capital watched their homes destroyed in heat-triggered blazes they never thought possible.

A resident of Wennington, a London suburb affected by Tuesday's fires, told CNN that the gardens on his street were "like a tinder box" in the days leading up to the fire. Stock lost his home, eight chickens and two beehives when the fire broke out.

"I didn't sleep last night. I was in the hotel room thinking how bad it could have gone. I just thank god that everyone got out alive," he said. "We've lost everything. But when we get back, we can clear the site, put some fences up, get a couple of mobile homes and we'll start again."

London had no available fire engines at one point in the afternoon amid unprecedented demand, a senior fireman with the London Fire Brigade's special rescue team told CNN.

In the United States, local leaders are urging caution and issuing health warnings as a heat wave that shows no sign of slowing before the weekend continues to bake the south-central regions of the country.

And in China, millions of densely-populated cities are responding to extreme heat. According to the China Meteorological Administration, at least 31 Chinese cities issued the second-highest orange alert warning, with temperatures expected to go up to 37 degrees Celsius (98 degrees Fahrenheit) in the next 24 hours.

Europe burns in record heat

Greece: On the outskirts of the Greek capital, Athens, firefighters have been tackling vast blazes that are being whipped up by wind. At least 600 people have been evacuated, including from a children's hospital, authorities said. One person has died and 30 have been transferred to hospitals in the capital's Attica region, the Greek Fire Service said on Wednesday.

"Our top priority remains the safeguarding of human lives. But also that of vital public infrastructure as well as citizens' properties," spokesperson Ioannis Artopoios said during an earlier televised briefing.

A firefighter tries to extinguish a blaze in Pallini, near Athens, Greece on July 20.

Huge clouds of smoke remain visible in the city on Wednesday, despite the efforts of hundreds of firefighters. Romanian fire crews have been drafted in to assist the operation.

Italy: Blazes are also being tackled in parts of Italy. Wildfires in Tuscany caused gas tanks to explode and forced evacuations overnight, Blazes are also being tackled in parts of Italy. Wildfires in Tuscany caused gas tanks to explode and forced evacuations overnight, according to the regional President Eugenio Giani.

Germany: In Alsdorf, western Germany, three residents and two firefighters were injured in a blaze on Tuesday, and much of the country is primed for more fires as temperatures rise on Wednesday.

France: In France, aircraft continued to dump water over burning landscapes. Fires have been raging there for a week now, though they advanced "very little" on Tuesday night in the Gironde region, according to local authorities. Smoke swirled over the Brennilis nuclear power plant in Brittany on Wednesday morning.

Just as UK Prime Minister was criticized for a lack of preparedness for the heat wave, France's Emmanuel Macron too is coming under pressure to respond more quickly to the heat and fires, which have already burned 25 times more land in France than in the same period last year, government spokesperson Olivier Veran told journalists on Wednesday.

Firefighters spray water on a wildfire in the Monts d'Arree, in Brittany, north-western France.

On Tuesday, the president of the fire-stricken Gironde region called for additional resources, including firefighting aircraft to be diverted there.

A campsite owner told CNN affiliate BFMTV on Tuesday that "we have demands" for Macron, who will be making a visit to the ravaged southwest on Wednesday.

"We hope that he will be able to very quickly order the public services to help us, to support us in the administrative steps to put the camp site in working order as soon as possible," said Stephane Carella, co-owner of Pyla Camping whose site was destroyed by fires.

France has been tackling wildfires for a week.

"Everything has gone up in smoke," he said, with some 90% of his property affected by the fire. Carella described the remainders of the site as "apocalyptic."

High temperatures rip through US

The baking weather in the US has so far been centered on parts of the south, and is raising particular concern about the welfare of elderly, vulnerable and homeless people.

In Texas, 14 prisons have no air conditioning and 55 have only partially-working systems, the Texas Department of Criminal Justice (TDCJ) told CNN in an email. Texas has had at least four heat waves this season, a hot streak that started impacting the state before the official start of summer. Since May 1, more than half their days have come with some level of heat alert.

As temperatures in neighboring Arizona reached triple digits on Tuesday afternoon, around 7,000 people lost power due to strong storms, a spokesperson for the Arizona Public Service Company said.

Much of the east coast will see temperatures in the 90s this week.

In some areas, such as Miami-Dade County and Phoenix, local governments have hired chief heat officers to help residents combat the heat.

Much of the country's north, and parts of Canada, are preparing for temperatures to soar too. Philadelphia declared a "heat caution" starting noon Tuesday and extending to until 8 p.m. ET Thursday, the city said in an email to CNN. It also declared a "code red" alert for homeless people in the area.

The Canadian government issued heat and severe thunderstorm advisories in at least four provinces on Tuesday.

3rd heat wave grips the South this summer, and experts say it will ...

(CNN) The third heat wave of the still-early summer is scorching the US South, and "it will get worse ... before it gets better," warns the National Weather Service.

Over 65 million people across 16 states are under heat alerts Thursday, with triple-digit heat indexes -- or "feels like" temperatures -- expected in cities including Dallas; St. Louis; Memphis, Tennessee; Little Rock, Arkansas; Birmingham, Alabama; Atlanta; and Raleigh, North Carolina.

The latest heat wave continues a trend playing out in recent weeks on every continent in the Northern Hemisphere -- and something that will be more frequent with human-induced climate change, experts with the Copernicus Climate Change Service said Thursday.

Above-normal temperatures will soar Thursday into the upper 90s and 100s Fahrenheit from the central and southern Plains to the Southeast. Paired with uncomfortable high humidity, it will feel like 110 to 115 degrees in some places.

And above-normal temperatures are forecast well into next week across the South -- well beyond the average of four days. Dallas already has seen several days above 100 degrees and is expected to continue the trend though at least midweek, putting this stretch in the running for the city's longest consecutive 100-degree streak since 2011.

A Southwest heat wave is on the way, the weather service warns ...

(CNN) A "dangerous and deadly heat wave" is on the way for the Southwest through the weekend, the Phoenix National Weather Service warns.

More than 30 million people are under heat alerts, and more than 50 daily high- temperature records could be broken through the weekend -- including in Death Valley, California, one of the hottest places on earth.

"Don't underestimate the heat! Heat is one of the most deadly weather hazards, so be sure to practice heat safety this week," the Sacramento National Weather Service tweeted.

"Record high temperatures will be [felt] across portions of Texas on Wednesday and Thursday and expanding into California on Friday," the Weather Prediction Center said Wednesday morning.

High pressure will create a heat dome over the Western US. The dome will trap any escaping radiation and send it back to the ground, while the sun's rays continue to penetrate through.

This, combined with arid soils from an extensive and long-term drought, will allow temperatures to rise to record levels over parts of California and the Southwest, with high temperatures from the upper 90s to over 110 degrees on Friday, the Weather Prediction Center said.

Here is when and where the heat will be the worst.

Texas-size heat leaves the state sizzling

"Hot again" is how the San Angelo National Weather Service started its forecast discussion Wednesday morning, as the mercury is on the rise in West Central Texas.

High temperatures will once again break the century mark this afternoon, and highs will intensify as the week progresses. Peak intensity is likely from Saturday through Monday, the San Angelo weather office said.

Major cities in Texas will see high temperatures over 100 degrees. Austin, San Antonio, Dallas, and Houston will likely hit the figure once, twice, maybe even three or more times before the week is over.

Above-average temperatures this weekend are likely to put the Texas power grid to the test.

During the state's heat wave last month , Texans were encouraged to conserve power by raising thermostats to 78 degrees and refraining from using major appliances during peak hours.

First heatwave of the year for Las Vegas and Phoenix

As this weather pattern remains over Texas into and through the weekend, it will expand into Southern California as well as Nevada and Arizona Thursday into Friday.

The first excessive heat event -- level 4 of 4 on the weather services experimental heat danger scale -- of the season is now upon us, the weather service's Phoenix office said.

"The first heatwave of the year has numerous climate sites threatening daily record highs and record warm lows," added the Las Vegas National Weather Service.

Death Valley is forecast to reach 121 on Friday. If it does, that will break the daily record of 120 set back in 1994.

Las Vegas will also flirt with daily records, with temperatures close to 109 both Friday and Saturday.

"High temperatures will approach 110 degrees already this afternoon and are expected to top out between 110 and 115 degrees across the lower deserts by Friday and last through the weekend," the Phoenix National Weather Service said.

Nighttime low temperatures will be near a record high as well.

JUST WATCHED Nighttime 'lows' more dangerous than highs Replay More Videos ... MUST WATCH Nighttime 'lows' more dangerous than highs 01:07

Las Vegas is only forecast to drop to 84 degrees Saturday morning, for example. The previous hot low temperature was 81 in 1996.

What makes this so dangerous is when temperatures remain this hot overnight, your body doesn't get a break from the extremes.

The heat should lessen early next week, the Phoenix National Weather Service said, with temperatures falling back to near-normal readings.

Both the Las Vegas and Phoenix weather offices also say Sunday might not be as hot as initially thought.

Interior California will see 'high' heat risk

Similarly in California, the worst will be Friday.

If you are on the California coast, you will escape the heat. The state's interior won't be so lucky.

"Warming and drying trend with triple-digit heat by late-week for the Central Valley," the Sacramento National Weather Service said. "The hottest day will be Friday, with little overnight relief from the heat."

The heat risk will be high -- level 3 of 4 -- on Friday for most of interior California.

JUST WATCHED These Americans are fleeing the West because of extreme heat Replay More Videos ... MUST WATCH These Americans are fleeing the West because of extreme heat 03:20

"Daytime temperatures could reach at least 100-105° across the Valley on Friday, which combined with warm overnight temperatures will produce high risk for heat impacts for the general public," the Sacramento weather office tweeted

All of the weather service offices had similar heat safety messages with tips for staying safe during excessive heat events: Try and avoid caffeine and alcohol, which can dehydrate the body. Instead, drink plenty of water and try to find air conditioning.

The drought is making this heat worse

An ongoing drought continues to plague the Southwest. And one of the many drawbacks of drought -- and dry soil -- is its impact on temperatures.

When there is no moisture in the soil or in plants, there is no evaporation or evapotranspiration, both of which are cooling processes that add moisture to the air and stabilize the air temperature.

"Basically, the drier the air, the easier it is to get to a high temperature," Bryan Jackson of the Weather Prediction Center told CNN Weather. "When there's more humidity, the temperature can be suppressed."

Dangerous heat wave scorching Europe

Doyle Rice

USA TODAY

An intense heat wave is baking Europe this week, with countries from Spain to England setting record high temperatures.

The hot days and warm nights are creating dangerous conditions for those unable to escape the heat, AccuWeather warned.

The heat shows no signs of letting up. "We have a lot of heat-wave days ahead of us," MeteoFrance forecaster Francois Gourand told the Associated Press, noting a wide swath of southern France from Toulouse to Lyon was facing temperatures up to 105 degrees through the middle of next week.

Germany and Poland will begin to feel the worst of the heat wave Thursday, AccuWeather said.

The high temperatures in Europe — following blistering, deadly heat waves in India and Pakistan that killed thousands in May and June — are helping push 2015's global temperatures to the highest in recorded human history, according to the Weather Underground.

Europeans are wary of heat waves, with the murderous heat of 2003 — when 70,000 died — still fresh in people's minds. In France, where 20,000 died in 2003, a nationwide heat emergency plan has been enacted this week, the Guardian reported. This includes opening cooling centers and checking on the elderly and vulnerable.

An all-time record high temperature for the United Kingdom in July was set Wednesday at London's Heathrow Airport, as the mercury soared to 98.6 degrees.

Wimbledon's tennis matches in London were being competed on the hottest day in the tournament's history, which goes back to 1877. A ball boy collapsed in the heat during a match Wednesday and needed to be taken off the court on a stretcher, the AP reported.

Some commuters outside a London subway weren't bothered by the sweltering heat. "I'm loving it. I can't complain," said Maggie Cloud, a university student who planned to relax in the park. "We pay so much money to go abroad to holidays, and now we have the weather here. It's cheaper," she told the AP.

Temperatures climbed to 104 degrees in Madrid on Monday, breaking the city's all-time June high at Gatafe Airport.

The heat is the result of an unusual bulge in the jet stream, which is allowing a massive ridge of high pressure to surge over the continent, bringing in extremely hot air from North Africa.

Even beyond the next few days, the weather pattern across much of Europe will feature warmer-than-normal temperatures through the middle of July with only a few brief breaks from the warmth, said AccuWeather meteorologist Adam Douty.

The most extreme weather events in 2021 | The Week UK

This year was regarded by scientists, politicians and environmentalists as pivotal in the global effort to take action on climate change.

Stark warnings and alarming forecasts were issued, as regions that were previously not considered to be on the frontline of climate change saw unprecedented weather events destroy homes and claim lives. As mercury levels in Moscow hit record-breaking highs in June, the United Nations Secretary General Antonio Guterres warned that the world was reaching a “point of no return”

In August, Boris Johnson described the latest global assessment from the Intergovernmental Panel on Climate Change (IPCC) as a “wake-up call to the world”. The “most comprehensive” climate report from the panel issued a “code red for humanity”, said The Independent, and stated the link between global warming and the increased rate and severity of extreme weather events.

Climate scientist Professor Hannah Cloke said that this year’s extreme weather events “ought to serve as a canary in the coal mine to spur faster action to adapt society to the reality of a changing climate”.

Here are some of the most costly weather incidents recorded so far this year.

Record-breaking snowfall, Madrid In the first weeks of 2021, Storm Filomena brought record-breaking levels of snow for Madrid and elderly Spanish citizens were warned to stay at home as temperatures plummeted. The heaviest snow for 50 years brought transport in and out of the city to a “standstill”, Euronews reported. The snowstorm caused around €1.4bn (£1.2bn) of damage, The New York Times said.

Storm Christoph, UK The period from 18 to 20 January 2021 was “one of the wettest three-day periods on record” for North Wales and North-West England, according to the Met Office. Homes in Cheshire were flooded, and residents were evacuated from homes in Manchester and Merseyside. Once Storm Christoph cleared, significant snowfall also led to travel disruption with icy conditions and road closures. Liberal Democrat councillor Richard Kilpatrick told the Manchester Evening News the atmosphere was one of “anxiety and disbelief”.

Cyclone Ana, Fiji Cyclone Ana “pummelled” Fiji towards the end of January, “just a month after category 5 Cyclone Yasa tore through the country’s northern islands”, The Guardian said. Satyendra Prasad, Fiji’s ambassador to the United Nations, said the cyclone – which caused more than 10,000 people to take refuge in 318 evacuation centres across the country – had left behind “a difficult recovery”.

Winter storms, Texas The Week US reported that 3.5 million businesses and homes were left without power in February as temperatures dropped to -13℃ in some areas of Texas. Power went out across the state, leaving many vulnerable people in extremely cold conditions. The total death toll rose from 151 to 210 in July, after a decision was made to include deaths caused by the collapse of the state electric power grid in the final count, The Guardian reported.

Dust storm, China Flights were grounded and schools shut in what the South China Morning post reported as the worst sandstorm in a decade. But what was widely reported as a sandstorm in China was, in fact, a dust storm - “and that’s much worse”, said The Conversation. The miniscule particles can travel “much, much further” than sand, and can cause health risks if they are “drawn deep into the lungs”. In Beijing, the sky became orange as dust and pollution caused hazardous air quality.

Flooding, New South Wales In March, Sydney and New South Wales (NSW) residents felt the effects of extreme flooding. The NSW State Emergency Service (SES) urged residents to take care of both their physical and mental health as heavy downpours lead to rivers and dams overflowing, with thousands evacuated from their homes.

Cyclone Seroja In April 160 people died in Indonesia after a tropical cyclone “hit a remote cluster of islands”, Climate Home News reported. Landslides and flash floods displaced at least 22,000 people, the news site adds. Reaching Western Australia days after it made landfall in Indonesia, residents in the town of Kalbarri, north of Perth, said the storm was “absolutely terrifying”, the BBC reported. Western Australia Premier Mark McGowan said Cyclone Seroja was "like nothing we have seen before in decades”.

Record temperatures, Moscow As temperatures reached 34.8℃ in Moscow, “the absolute record for any day in June was hit”, The Moscow Times reported. The “abnormal temperatures” of the “record-breaking heatwave” weren’t just recorded in the capital; Penza, Vologda and Petrozavodsk also broke heat records during the month.

Heat dome, Pacific Northwest Soaring temperatures across the Northwest United States “rewrote the record books” this year, National Geographic reported. The “heat dome” was the “most dramatic example” of an extreme weather event, said The Guardian’s global environment editor Jonathan Watts, and the meteorological phenomenon led to evacuations across states that weren’t “remotely prepared for the heat”. Lytton, a village in Canada’s British Columbia, was “engulfed and largely destroyed by a wildfire” as a result of the temperatures, National Geographic continued. Blistering Pacific Northwest temperatures should act as a wake-up call

Wildfires, heat strokes and deaths: Unite to fight the climate crisis

Dr. Thomas K. Lew

Opinion columnist

Parking at the Northern California hospital where I work, I quickly break into a sweat during the 80-foot walk to the entrance. It’s 100 degrees outside, and it’s only 8 a.m. Outdoors, I can feel the intense sunlight on my skin, but inside the cool wards of the hospital, I experience the effects of the recent heat wave in my soul: My first patient of the day is gravely sick from severe heat stroke.

A healthy athlete, he became severely lightheaded, disoriented and unable to put together a coherent sentence. He had only spent 15 minutes in a car driving without air conditioning, but these effects were lasting hours. At one point, we thought he was developing a true stroke in his brain and not just heat stroke.

He’s not the only one suffering. I am seeing more and more people experiencing adverse health consequences of a warming environment. Put more bluntly, more people are getting sick from climate change. I am seeing them today. Not years in the future. Right now. For our health and survival, we need to be brave enough to stop and even reverse climate change by supporting state and national policies that strive to do this.

Heat stroke, dehydration and wildfires

That our planet is warming up is indisputable, and virtually all scientists agree that it is worsened by human activity.

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Extreme temperatures and extreme weather events like hurricanes and tropical storms are becoming more frequent. The recent heat wave on the West Coast is another symptom of climate change, with the thermometer reaching triple digits for days at a time. New records were set, including the 130 degree mark in Death Valley – the second highest temperature on Earth ever recorded.

People have found fun in the extreme temperatures, cooking breakfast or baking cookies using just the sunlight. But the heat can be deadly for our most vulnerable. At least 150 deaths have been attributed to the heat in the Pacific Northwest during this recent unprecedented heat wave. If British Columbia, Canada, is counted, then that number nears 1,000 people. In my hospital, we are seeing more heat strokes and dehydration cases, especially among our elderly and homeless population.

Can-do and optimistic:We're conservatives and we're fighting against climate change

This is all happening as wildfire season is starting. Last year in California, the skies turned an ominous shade of red as much of the West Coast burned. Despite efforts in forest management, uncontrolled wildfires are raging once again. The environment is so dry, in fact, that one wildfire was set off by a golf club sparking when it struck the ground.

The health consequences are palpable. Last year, our medical wards filled with the sounds of wheezing lungs from struggling patients, both from COVID-19 and also pulmonary damage from wildfire smoke. Climate change continues to make these fires all the more frequent.

No time left for political bickering

President Joe Biden has argued that fighting global warming is a key priority in American infrastructure – but it’s more than that, it’s a priority for humanity’s infrastructure.

We cannot turn this battle into more political bickering; we don’t have the time. We need to push our elected officials to support policies curbing carbon emissions and promoting clean energy. We need to invest in the science. We need to believe the science.

Bipartisan infrastructure bill is a start:Climate change is no longer other worldly, and inaction is no longer an option

Aside fromrising sea levels, destruction of animal habitats, melting polar caps, increased flooding and the other myriad existential hazards, we are still at grave direct health risks with worsening climate change. And those dangers are now. Nowhere is this more evident than inside a hospital, filled with patients suffering from the increasing heat and smoke. More than just causing an unpleasantly hot walk across a parking lot, climate change will certainly lead to more death and suffering unless we pull together across the political spectrum and act before it’s too late.

Thomas K. Lew, MD, is an assistant clinical professor of Medicine at the Stanford University School of Medicine and an attending physician of Hospital Medicine at Stanford Health Care – ValleyCare. All opinions are solely his own. Follow him on Twitter: @ThomasLewMD