A deadly heat wave has swept over Europe

Records are crashing and hundreds have died as a dangerous heat wave prompts weather alerts far and wide across Britain, France, Spain and Portugal. Temperatures have surged above 110 degrees (43 Celsius) over the Iberian Peninsula, and the United Kingdom is forecast to see its hottest temperature ever recorded early next week.

The Health Ministry in Spain has confirmed 84 heat-related deaths, while 238 fatalities have been reported in Portugal.

Red "extreme" heat warnings have been hoisted in parts of the U.K. for the first time on record where the hottest weather is forecast Monday and Tuesday. Britain's Met Office is describing the situation as a "national emergency," warning that the heat will have "widespread impacts on people and infrastructure."

The red warning covers much of central, northern, eastern and southeastern England, including London.

"For the first time, temperatures of 40°C [104 Fahrenheit] have been forecast," the Met Office wrote.

A somewhat less dire amber heat warning surrounds the red warning and includes much of the remainder of England and Wales, while expanding north into southern Scotland.

The heat about to swell over the U.K. has been building over Portugal, Spain and France.

The majority of Spain and southern and western France are blanketed by warnings, with Météo-France writing that the heat will “threaten” everyone — “even [people] in good health.” In Spain, temperatures soared as high as 112 degrees (44.3 Celsius) Friday, while Madrid matched its highest temperature on record Thursday.

After temperatures surged as high as 113 degrees (45 Celsius) in Portugal earlier this week, the heat has eased some but two of its 18 districts remain under red warnings Saturday.

It’s worth noting that air conditioning — common in the United States — is a rarity in parts of northern and western Europe, because excessive heat of this nature is unusual. In the U.K., for instance, where residents are bracing for highs in the mid-90s early next week, the average high for mid-July is in the 70s.

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The blistering heat is combining with ongoing drought to brew what Copernicus, a climate monitoring agency, is calling a "very extreme" wildfire risk for the Iberian Peninsula, as well as France and Greece.

Reuters reports raging wildfires in southwest France and Spain Saturday, forcing thousands of evacuations, while fire activity lessened in Portugal.

The United Kingdom will see its hottest weather Monday and into Tuesday. That’s when temperatures could hit a very rare number — 40 Celsius (104 Fahrenheit). The highest recorded temperature for the U.K. is 101.7 degrees (38.7 Celsius), which was set in Cambridge in 2019.

"Currently there is a 50% chance we could see temperatures top 40°C and 80% we will see a new maximum temperature reached," Met Office chief meteorologist Paul Gundersen said in an online news release.

The Met Office predicts highs of 95 (35 Celsius) and 99 degrees (37 Celsius) in London on Monday and Tuesday. Weather.com, meanwhile, calls for London to hit 101 degrees Monday and 99 on Tuesday; the average afternoon high during July is 74 degrees. Readings over 84 are rare.

"Nights are also likely to be exceptionally warm, especially in urban areas," Gundersen said. "[I]t is important people plan for the heat and consider changing their routines. This level of heat can have adverse health effects."

The Met Office, ordinarily reserved in its verbiage, didn't mince words when identifying human-induced climate change as a factor in the potentially unrivaled heat.

"The chances of seeing 40°C [104 degrees] days in the U.K. could be as much as 10 times more likely in the current climate than under a natural climate unaffected by human influence," said Nikos Christidis, a climate attribution scientist at the Met Office. "The likelihood of exceeding 40°C anywhere in the U.K. in a given year has also been rapidly increasing, and, even with current pledges on emissions reductions, such extremes could be taking place every 15 years in the climate of 2100."

A Level 4 U.K. Health Security Agency Heat-Health Alert has been hoisted to raise awareness for the exceptional temperatures.

"This level of alert is used when a heat wave is so severe and/or prolonged that its effects extend outside the health and social care system," the Met Office wrote. "At this level, illness may occur among the fit and healthy, and not just in high-risk groups."

The worst of the heat is yet to come in France, with temperatures likely to peak Monday. Some weather models even simulate high temperatures approaching 116.6 degrees (47 Celsius), though that’s likely apocryphal. In any case, it’s probable some residents of southern France near the Spanish border could see readings in the range of 105 to 110 degrees (40 to 43 Celsius) range. That’s commensurate with the 107.6 degrees (42 Celsius) predictions put forth by Météo-France, the country’s weather service.

The agency tweeted that Monday has the potential to be one of the hottest ever recorded across France. The record would be surpassed if the national average temperature — a countrywide calculation that involves averaging the high and low temperatures for a day throughout the country — makes it above 84.9 degrees (29.4 Celsius).

Météo-France also noted the role that human-induced climate change is playing in amplifying the existing heat wave. It cited a historic episode in July 2019 when the temperature in Paris soared to an unprecedented 109 degrees.

"Human influence on the climate has multiplied by at least 20 the probability of this event and made this type of event warmer by 2.1°C [3.8 degrees]," tweeted Météo-France. "The same calculation for the current heat wave would give close figures."

Weather.com is calling for Paris to hit 103 degrees Monday and 104 on Tuesday, compared with an average mid- to late-July high of about 75 degrees.

In Spain, an “extreme risk” of heat has warranted a red alert to be issued in five provinces — with forecast highs up to 111 degrees (44 Celsius). Spain has 50 provinces; the remaining are mostly under orange “important” heat alerts and lesser yellow alerts.

In Madrid, the high is forecast to hover near record levels or around 105 degrees (41 Celsius) through the weekend.

Instigating the heat is something called a “cutoff low,” or a low-pressure system that has become pinched off from the jet stream. It’s analogous to paddling a boat through a pond and watching a whirlpool shed off the oar and continue spinning aimlessly. In this case, the low is a self-sustaining swirl of counterclockwise-spinning winds wrapped about a lobe of high-altitude cold that’s whirring around a few hundred miles southwest of Portugal over the open northeast Atlantic.

Because it's no longer nestled within a dip in the jet stream and subsequently shuttled west to east, there's nothing to really scoot it along. As a result, the cutoff low will spend days sitting in place and spinning, with southerly winds on the eastern side of the system pumping African heat northward toward Western Europe and the U.K.

While the heat will gradually ease from west to east in Europe next week, it marks the latest in several European heat events that have been exacerbated by human-induced climate change. While human influence is not the cause of the hot weather, it tips the scales toward more frequent, intense and prolonged heat waves.

It has been just over three years since an unprecedented heat wave baked Europe, sending temperatures skyrocketing. Paris hit an all-time high of 109 degrees (42.8 Celsius). Last month, a heat wave set hundreds of records throughout Europe amid the continent’s second-warmest June on record.