Mediterranean heat spells DANA chaos

The Spanish Meteorological Agency reports that June 2025 is going down in history as a record-breaking scorcher. Temperatures have soared to unprecedented heights across the country.

Spain could expect to have around five days of record warmth in a typical calendar year. This June alone, however, saw nine record breakers, with temperatures hitting at an astonishing 46°C in El Granado, Huelva, the highest ever recorded for a June in Spain. The month’s average temperature reached 23.6°C, a jaw-dropping 3.5°C above the 1991–2020 reference period, overtaking even the historical averages for July and August (23°C). AEMET claims that such a departure from the norm cannot be matched.

The heated Mediterranean may lead to further DANA chaos

Experts are focusing their attention on a trend that is more sinister than the scorching air temperatures: the rapid heating of the Mediterranean Sea. Surface water temperatures along Spain’s Mediterranean coast have reached between 28 and 30°C, with some areas, like Sa Dragonera near Mallorca, hitting 30.55°C on July 1, a record for the Balearic coast so early in the summer. This is a much higher number than usual for this time of the year. In the eastern Cantabrian Sea, waters are also unusually warm at an average of 24°C.

The Mediterranean is warming 20 per cent faster than other seas, and an average surface temperature of 28.47°C in August 2024 was recorded, a record which looks likely to be shattered this year, according to the Copernicus Climate Change Service.

The Mediterranean region is expected to experience excessive rainfall due to its high temperatures

This marine heatwave has negative implications. The heat of the sea will increase the humidity in the atmosphere, which will intensify the oppressive summer heat. Experts warn the Mediterranean’s thermal reactivity, i.e. its ability of retaining heat longer than atmospheric temperatures, can predictably increase autumn storms. The result of the collision between cold air masses coming from the north and this overheated seawater fog can be disastrous.

This was the cause of the devastating DANA in Valencia, Castilla La Mancha, and Malaga that caused flash flooding. AEMET (Australian Meteorological Agency) and the World Meteorological Organisation claim that the increased water vapour in the atmosphere due to warmer seas increases the intensity of storms. For every 1°C increase in sea temperature, atmospheric water vapour rises by at least 7 per cent, seriously raising the risk of extreme rainfall.

The rapid and early warming of the Mediterranean has caused Spain to fear even more severe weather this autumn.