Record temperatures in the United Kingdom (almost 35º in Kew Garden, something exceptional even for summer according to the meteorological service), France and Spain. A heat that has left images of citizens sheltering in the shade or in desperate search for a source. The phenomenon behind it has been called a “heat dome”, “a very visual way of explaining a situation in which a mass of warm air is trapped for several days under an area of high pressure. It’s as if the atmosphere put up a cover: “The air descends, compresses, heats up and, in addition, makes it difficult for cooler air to arrive,” explains Mar Gómez, doctor in Physics and head of the Meteorology area at eltiempo.es.
Is it the same as Saharan air dorsal? For Jorge Olcina, professor of Regional Geographic Analysis at the University of Alicante, “it is now called a dome, but traditionally it was what we called a ridge or a Saharan air ridge, which is what normally shapes heat waves. On this occasion they did not want to call it a heat wave, although records have been broken in some regions. But, when it comes to names, I always say that you have to go by what people say, the perception that the population has. And we have really spent days with very high temperatures, well above what is usual for the end of May. The professor points to the arrivals of this dorsal to the Peninsula. «Traditionally we are the first territory that encounters the air of the Sahara Desert on its journey towards southern Europe. We are closer to the focus of this warm mass. Now it is called a dome because it is true that the configuration it has, seen in a section of the atmosphere, would be like a small mountain, a small hill of warm air. This presence of warm air prevents the formation of cloudiness and precipitation,” he comments.
Conspiracy
After the appearance of the “dome”, conspiracy theories have multiplied on social networks. There are even those who claim that this phenomenon has been caused “by elites using chemicals that planes leave in the sky,” comments the fact-checking platform verification.cat. And the truth is that, in the face of extreme phenomena, theories and conspiracies multiply. This is stated, for example, in a study published in 2025 by the Center for the Fight against Digital Hate (CCDH). According to this organization, Conspiracy theories about extreme weather events spread faster than life-saving alerts on some social networks. For the study, they analyzed 300 viral posts during extreme events such as the wildfires in Los Angeles and hurricanes Helene or Milton. Following these events, the report notes, the platforms “amplified conspiracy theorists while leaving out emergency information.”
In this case, is it the expression that induces the appearance of theories or the exceptional nature of the episode? Is a hot month of May so strange? According to the AEMET, this heat episode has been extraordinary since The days 22, 27, 28 and 29 broke records and were the days with the highest average temperature in the whole of Spain for their specific dates since 1950. According to Copernicus data, May 2025 was the second warmest on the planet with global temperatures 0.52º above average. 2020 also stood out for being the warmest since 1965, etc. For climatologists, the series and the predominance of records of warm days reflect the altered atmosphere: “Last month, 16 warm days and no cold days were recorded,” states information from Europa Press prepared from AEMET data. “We have to get used to it in Spain,” says Olcina. «Summer starts earlier and ends later. What we see in recent years is that the horizon for obtaining that degree and a half worldwide is being shortened, so to speak, compared to the reference period that began in 1880, when approved scientific measurements began throughout the planet. The horizon of the two degrees is also shortened. As the UN report says, and Copernicus and the Berkeley Earth Climate Center have also pointed out, at the beginning of the next decade, around 2032 or 2033, we will have globally reached that degree and a half. Furthermore, it is expected that During the 2050s we will reach two degrees. Therefore, the time horizon that we previously placed at 2100 is being drastically reduced. Lately I say that the warming process is a little out of control: it is going faster than previously thought and is producing many effects. Above all, it mobilizes a lot of energy in atmospheric processes and is generating extreme events with significant damage,” explains the Alicante researcher.
Summer
Despite the lull these days, the models also suggest that the summer of 2026 will be very warm. «That we have warm arrivals in spring or early summer is not unusual. What is increasingly drawing attention is the intensity, persistence and geographical extension of these episodes. Copernicus already noted that April 2026 was the tenth warmest April recorded on European land, with an anomaly of +0.50 ºC compared to the period 1991-2020. In Spain, furthermore, seasonal forecasts for the May-July quarter already pointed to temperatures above normal throughout the country. And the seasonal prediction for June, July and August points to a high probability that the average temperature will be in the upper tertile throughout Spain. That is, the most likely scenario is a warm or very warm summer,” says Mar Gómez.
The doctor in Physics has just published The Climate Tick, a book in which she reviews the science behind the models that talk about climate and with which she aims to dismantle some theories. In addition, it warns about geoengineering solutions that are presented as viable alternatives to combat warming. “Intervening in the atmosphere is risky,” he says in a recent interview.
Record until 2030
The latest official alert on climate trends has just arrived from the World Meteorological Organization. The organization warns of more record years of heat until 2030 and an Arctic with increasingly accelerated melting. The probability of breaking a new annual heat record before 2030 is 86%, while the probability of temporarily exceeding the threshold of 1.5 ºC with respect to pre-industrial levels reaches 91%. «For the Iberian Peninsula this does not mean that every day will be extreme, but it does increase the risk of experiencing more frequent, intense or earlier episodes of heat. Our territory is in a particularly sensitive area: the Mediterranean is warming rapidly, droughts can intensify and heat waves have a very direct impact on all of us,” says Mar Gómez.
Adaptation
A few days ago the first educational center in Asturias closed due to heat. The day before, the Ministry sent a guide to action in the face of high temperatures. Is it necessary to adapt? «There are impacts that are already practically irreversible on a human scale, as part of the accumulated warming in the oceans, the loss of glacier mass or the rise in sea level that is already underway. But that doesn’t mean all is lost. This is a very important idea: every tenth of a degree counts. Each additional fraction increases the risk of heat waves, droughts, extreme rainfall, fires, biodiversity loss and health problems. We are more prepared than a few years ago because there are more warnings, more heat plans and more awareness. But we are still not there enough.”
The first forest fire of the campaign
►This week the first forest fire of the season was declared in Murcia. After a record 2025, with 393,000 hectares destroyed in 8,000 fires, the Government advanced the fire campaign to June 1, just days before this fire broke out.
In parallel, a report was published by the Independent Trade Union Center and Civil Servants (CSIF) that warns that there has been a lack of preventive planning during the winter and denounces the insufficiency of staff and the aging of material resources, which “places numerous territories in a position of vulnerability to the arrival of high temperatures.”