The United Kingdom, France and northern Spain: the heat advances and breaks records

Barcelona / LondonThe full summer atmosphere that has accompanied us for days is leaving thermal records that, in some cases, have never been seen in the middle of May. The United Kingdom, France, and Cantabria and Asturias in Spain are some of the places where unusual values have been recorded in a heatwave with few precedents, both for its date on the calendar – at the end of meteorological spring – and for its intensity and persistence, with many days widely above the climatic average. Also in Catalonia, in recent days, temperatures more typical of early July than of May have been reached, with thermometers approaching 35 °C in some territories.

The cause of all this is the powerful anticyclone that has been installed over Western Europe since a little after the middle of the month. This atmospheric situation is blocking any possible low-pressure system approaching from the Atlantic and preventing the weather from changing. Combined with a sun that is already intense and long-lasting and heats the surface a lot, the anticyclone shoots up temperatures due to subsidence, which is the downward movement of air layers from upper levels, compressing the most superficial air layer, the one that surrounds us, and causing it to gain even more degrees.

Although it is not an exceptional phenomenon, in this case it is leaving unusual or unprecedented records on the continent and the British Isles. In the United Kingdom, temperatures exceeded 30 °C on Saturday, the first time this has happened in May since 2012. But this Monday, a new heat record has been registered in the middle of May, in an episode of unusual temperatures affecting a large part of the country. Thermometers reached 34.8 degrees in Kew Gardens, in southwest London, and widely surpassed the previous historical maximum of 32.8 degrees. In fact, this record also surpasses the station's June record.

The day has left up to three new records and becomes the hottest day registered in May, as well as the warmest holiday Monday on record. At Heathrow Airport, the maximum temperature record for May in the country was reached this very Monday, with 33.5 °C.

Furthermore, the early hours of this Tuesday have been historic: the minimum temperature at Kenley Airfield, south of London, did not drop below 21.3 °C. This is the first tropical night ever recorded in May in the United Kingdom, and it shatters the record for the highest minimum temperature set just the day before (19.4 °C). These are extremely high temperatures that in countries not accustomed to extreme heat are more difficult to endure, due to the lack of air conditioning systems.

"Early" heat in France

The heatwave has not been limited to England. Wales has recorded its hottest May day, while Scotland and Northern Ireland have also reached the highest temperatures of the year so far. This episode, unprecedented for the time of year, with still four weeks to go until summer, is more typical of July or August than late May. In some areas of the country, values have been up to fifteen degrees above the usual average. According to forecasts, the anomalous heat will continue for at least one more day and in southeast England, today's records could be surpassed again.

In France too, the anticyclone has brought higher than normal temperatures and it has been necessary to activate a heat warning for intense heat for the first time in a May. According to the national meteorological service (Météo-France), this is an "early heat episode" that mainly affects the west of the country and the capital. The heatwave is spreading north with thermometers above 30 degrees, and only parts of the Atlantic and Mediterranean coasts are escaping these high temperatures. Further south, in Portugal, seven municipalities in the Algarve and about thirty in the interior of the country are at "maximum" or "very high" risk of fire due to rising temperatures, according to the Portuguese Institute of the Sea and the Atmosphere (IPMA).

Records, far from Catalonia

For now, however, this heatwave is not breaking records in Catalonia, where the context of climate crisis has made it common in recent years for intense heat to visit us before June. The episode's maximum was, provisionally, 36.1 °C recorded last Friday in Seròs, in Segrià. Nevertheless, it is foreseeable that the mercury will climb higher between Wednesday and Friday, when 37 or 38 °C could be exceeded in the regions of Ponent and in parts of the Ebro valley interior.

In Barcelona, and coinciding with the second Easter long weekend, a day with a fully summery atmosphere has been experienced. On Bogatell and Nova Icària beaches, the sand has been filled with families, groups of friends, and tourists who wanted to take advantage of the day to "inaugurate the summer season" and have "the first swim" with water that "is still cool and very clean," according to ACN. The atmosphere has also moved to terraces and beach bars, which have already reached 80% occupancy on weekends, with restaurateurs optimistic about a May that they describe as "very good".

The situation in Catalonia is quite different from the Cantabrian coast. This is the case in Asturias: Oviedo exceeded the record for the maximum temperature in a May month on Friday... recorded the day before. They reached 35.5 °C. Records have also been registered in Cantabrian towns such as Torrelavega or Santillana del Mar, while in the southern peninsula they have already approached 38 or 39 °C, although without reaching any unusual values.