If you're traveling to Alicante, Murcia or Valencia today, don't expect to cool off if you take a bath. The water will be 30ºC on the beaches of Dénia, Xàbia, Cartagena or La Malvarrosa, while outside, on the sand, the maximum will be between 29ºC and 31ºC. What does it mean? That today at Malvarrosa beach, in the Valencian capital, inside the water, the temperature will be higher than outside.
Nor do you expect it in the Balearic Islands, Castelló or Tarragona, where you will find the sea at 29ºC. At Caldetes beach (Maresme) the water will be at 28ºC, and if you go further south, in l'Arenal, in l'Hospitalet de l'Infant, the forecast indicates 27ºC, two degrees less than in Benicàssim, in Castelló. In reality, in all the stretches of the peninsula's east coast, today there is no beach where you can swim at less than 25ºC; although if you are satisfied with this temperature, you can visit the regions of Girona.
The temperature at the buoy in the port of Barcelona was 27.3ºC yesterday, therefore, the record in the sheet of water close to its beaches would be a little higher, since the temperatures near the coast are a little higher. In Tarragona, if there's no wind, it's "like getting into a hot bathtub", say the meteorologists
The water in the Spanish coastal areas has reached, in mid-July, an average of 24.6 °C, which is about 2.2 °C more than is normal for this time of the year. This is indicated by the State Meteorological Agency (Aemet). The measurements refer to average temperatures on both the Mediterranean and Atlantic coasts.
These days are "widely surpassing the records of the two previously warmest years"; this is in 2015 (when 24°C was reached) and 2022 (23.7°C), according to Aemet. This situation is "unprecedented in mid-July in the entire historical series", which began in 1940.
In the same way, in the Gulf of León (in front of the Costa Brava) it has been at abnormally high levels, specifically three degrees above average.
This whole situation, in a context of global warming of the oceans, has been considered particularly "worrying" by Rubén del Campo, spokesperson for Aemet, given that summer is far from over. The forecast is that this warming of coastal waters will continue in the coming weeks, as explained by José Luis Camacho, also a spokesperson for Aemet.
The culmination of this warming does not necessarily coincide with the heatwave, but "will be delayed". "The peak of the sea water temperature will be reached at the end of August, therefore, the forecast is that we still have a month for it to continue rising", he indicates.
"The Mediterranean already shows a clear tendency to warm up; but this year the Bay of Biscay and the Cantabrian coast have warmed up a lot", notes José Luis Camacho. In these areas of the Atlantic there have been heat waves, which is one of the characteristics that best define the months of June and July this year. The warming has not only been in the Bay of Biscay, but in the entire North Atlantic.
Usually, the measurements of the coastal waters are not made next to the beach, but are taken by making a short journey by boat, are taken from buoys (at varying distances from the coast) or correspond to some facility in the ports, where these measurements are made.
The dynamics of water temperature on the coast is influenced, as a basic factor, by the meteorological situation in the area in question, but secondarily by currents and the outcropping of deep water, which is much cooler.
In Spain, in general terms, bathing waters with higher temperatures occur in the Balearic Islands or Murcia, while the greater the proximity to the Strait of Gibraltar, the higher the probability of outcrops of colder waters. "The current comes from the Atlantic, a fact that, together with the winds from the land, causes the water from the bottom to rise", adds Camacho.
