It’s been barely three weeks since a historic spate of extreme temperatures baked Western Europe, smashing all-time records in Britain. Now a new heat wave is building over the continent, with alerts issued and more records in jeopardy.
By Thursday, much of France and southern parts of the England are expected to see high temperatures 18 to 27 degrees (10 to 15 Celsius) above normal, with highs in the 90s (above 32 Celsius) rather than the 70s (above 21 Celsius).
Amber warnings, the second-highest level, have been hoisted in southern parts of England by the UK Met Office.
In mid-July, the Met Office issued its first-ever red warning for "extreme" heat, with more than 40 weather stations surpassing the previous record 101.7 degrees (38.7 Celsius) in the United Kingdom. Several stations even spiked to 104 degrees (40 Celsius), a feat that was made 10 times more likely because of human-caused climate change.
A large stretch of western and northwestern Europe will be affected by the upcoming heat wave, with the risk of wildfires accompanying the spiking temperatures. It follows Europe’s sixth-hottest July on record.
Driving the heat is a ridge of high pressure, colloquially known as a heat dome, which will be parked directly over the United Kingdom by Tuesday night into Wednesday. In addition to bringing hot, sinking air, it will deflect any inclement weather - making for incessant sunshine.
In the UK, temperatures are expected to peak Friday into Saturday before easing next week. Highs will generally range between 85 and 95 degrees (29 to 35 Celsius), though a few locales may approach 96 or 97 (35.5 to 36 Celsius). It’s unlikely that anyone will hit the century mark.
A Level 3 out of 4 heat wave action alert has been issued by health officials, who urged residents to "look out for others, especially older people, young children and babies and those with underlying health conditions." Officials also recommended that the public limit alcohol consumption.
The Met Office is forecasting London will see highs in the upper 80s to near 90 (30 to 32 Celsius) Thursday through Sunday. Showery weather will arrive to kick off the workweek. The average early August high temperature in London is closer to the lower 70s (low 20s Celsius).
Met Éireann, Ireland’s equivalent to the US National Weather Service, also issued a weather advisory for the country, warning of “heat stress, especially for the more vulnerable of the population,” in addition to a high UV index. It’s worth noting that relatively few residents have air conditioning installed in their homes.
Eighteen departments in France also are under orange heat alerts, and Météo France is calling for temperatures in southwestern parts of the country reaching 97 to 102 degrees (36 to 39 Celsius), with an isolated 104 degree (40 Celsius) reading not improbable.
Paris is predicted to hit 93 on Wednesday, 92 on Thursday and 94 for Friday.
In Spain, which had its hottest July on record, an orange warning for heat is in effect just south of Madrid - where maximum temperature could approach 104 degrees, with many other areas under yellow alerts. But the core of the heat dome should remain farther north in western Europe.
Exacerbating the heat is ongoing severe drought, plaguing many parts of western Europe.
According to climate historian Maximilano Herrera, it was record dry in some parts of England, including in London. He tweeted that the city had seen "virtually no rain" during the month of July, with less than a millimeter recorded. July typically features closer to 1.8 inches (45 millimeters) of precipitation, with an average of 8 rainy days during the month.
The Met Office reported 13 counties across southern and eastern England posted their driest July on record.
There are concerns that the hot, dry atmosphere, combined with parched antecedent conditions, could support the risk of wildfire. The UK’s Cornwall Fire and Rescue Service wrote that fire risk “is now very high to exceptional,” and that firefighters were especially busy over the past weekend. They urged individuals participating in outdoor recreation to avoid campfires and bonfires.
France is also enduring an exceptional drought, one of its worst on record, according to Meteo France. Rainfall was the country’s lowest observed in July and 85 percent below normal.
Nearly 40,000 residents in France were forced to evacuate from wildfires during the third week of July, with similar blazes raging in Spain and Greece.
The very dry conditions are once again generating a very high fire danger, especially in southern France.
While the core of the heat will be situated over the southern UK and France Thursday through Sunday, above-average temperatures will also swell from the Netherlands through southern Scandinavia. The heat will retreat from western Europe early next week, shifting toward eastern Europe.
It’s well-established that human-caused climate change is amplifying the severity, duration and frequency of high-end heat events. In addition to the ultrarare heat that baked the UK last month, a similar-magnitude event brought record-shattering temperatures, including a high of 109 degrees in Paris, in late July 2019.