
The energy accumulated in the sea during the summer intensifies precipitation without the need for a DANA or deep trough.
The Aemet explains that the extreme heat of the Mediterranean, which broke records in September, is the main driver of the torrential rains in eastern Spain, causing fatalities in Catalonia and activating red notices in Barcelona and Girona.
AI-generated summary
The Balearic Sea exceeded 26°C at the end of September, marking a record since 1940. The Copernicus report warns that the oceans absorbed 23 zettajoules of energy in 2025.
The delegation of the State Meteorological Agency (Aemet) in the Valencian Community explained this Sunday that the sea is releasing these days "the large amount of energy accumulated during the summer" in the form of extreme heat. That would be, according to experts, the main reason for the exceptional episodes of precipitation that have been recorded this week in the Mediterranean area.
Meteorologists from the state agency indicate that there is no marked atmospheric situation, with the presence of a dana, a deep trough or a jet of wind in lower layers that could explain the torrential rains recorded in communities such as Catalonia, where at least two people have died and there is also one missing. According to them, "the anomalous temperature of the western Mediterranean explains these exceptional episodes better than atmospheric dynamics," they point out.
An example is that, at the end of September, the Balearic Sea exceeded 26°C and broke temperature records for those dates since at least 1940. The extremely high temperature of the sea explains the intensity of the torrential rains because it represents an enormous contribution of energy and humidity to the atmosphere.
With this scenario, Aemet calls for great caution if traveling this weekend and warns that the greatest adversity moves towards the north with a red warning activated from 9 p.m. on the coast of Barcelona that tomorrow extends to other regions of Barcelona and Girona.
Effects of global warming
Last week, the tenth State of the Ocean Report from the European Union's Copernicus Marine Service warned that the oceans absorbed an additional 23 zettajoules of energy in 2025, an amount equivalent to about forty times all the energy consumed by humanity during that same year.
Copernicus emphasizes that rising water temperatures fuel marine heat waves, can intensify storms and contribute to sea level rise through thermal expansion of water, in addition to altering ecosystems.
The study, prepared by Mercator Ocean International for the European Copernicus program, which has included contributions from 125 scientists from Europe and the rest of the world, confirms that the increase in oceanic heat content has accelerated since 1960 and warns of increasingly profound changes in the planet's seas.
AI outlook — possibilities, not facts
Extension of red notices to regions of Barcelona and Girona.
Very likely · Within hours
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