Heatwaves give no respite: we already have the third of the summer upon us

BarcelonaThe second heatwave of the summer is just ending and the third is already showing its face. This Friday is the last official day of the episode that in recent days has shattered heat records across the country. Thermometers have begun to drop in recent hours, although they come from so high up that the atmosphere remains fully summery, with maximums that will still reach 40°C in Ponent. Meteocat maintains yellow alerts activated for intense heat in this area on Friday, as well as in Baix and Alt Penedès, Garraf, and Baix Llobregat.

On Saturday, the mercury will drop even further and the second heatwave will be declared over, despite the weather remaining very warm. But it will be a brief, fleeting respite, as from Sunday onwards the thermometers will begin to rise again, and will rise even more next week.

The arrival of a new very warm air bubble from North Africa - driven by the counter-clockwise rotation of a low-pressure system located west of the Peninsula - will once again spread across Western Europe, especially the Western Mediterranean, and therefore will fully affect Catalonia.

Initially, the Meteorological Service of Catalonia (Meteocat) had considered this new rise in suffocating weather as a continuation of the second heatwave. But this Friday the agency explained that it has finally decided to consider this new situation as the third heatwave of the summer. The two heatwaves are part of a long heat episode that will last at least twelve days.

The third heatwave will officially begin on Sunday, July 12, and will last at least until Thursday, July 16. Saturday will be the first day without alerts for intense heat anywhere, but looking ahead to Sunday, Meteocat has already activated the first warnings for intense heat of the new episode in Ponent, the Pyrenees, and the Pre-Pyrenees.

More heat than in recent days?

The new North African warm air bubble will be even more intense than the previous one. It is estimated that temperatures at an altitude of 1,500 meters will range between 26 °C and 28 °C, a good couple of degrees higher than during the second heatwave. Therefore, this may lead us to think that some of the records set in recent days could be surpassed, especially in the interior of the country.

However, there will be some factors that may prevent the thermometer from soaring so high. First of all, there will be more maritime humidity. This is a factor that can slow down the mercury but, on the other hand, will increase the feeling of stuffiness, especially on the coast.

Finally, the most important factor will likely be that this warm gust will be accompanied by a lot of suspended Saharan dust. Therefore, the presence of these particles will cause the sky to be dusty, which may slightly reduce the impact of solar radiation and, at the same time, prevent such extreme temperatures.

In any case, and with the current maps, many maximums of 36 °C to 41 °C are expected again, higher in Ponent and the Ebro valley, where 42 °C or 43 °C could be surpassed again. The peak torrid period of the episode is foreseen between Wednesday and Thursday. All this with a very heavy atmosphere on the coast and generally sleepless nights, with tropical or torrid minimums. A warm bubble that will also affect other countries in Western Europe, such as France.

When will the extreme heat end?

If we take a look at the medium-term forecasts, the different meteorological models indicate that from Friday and next weekend, thermometers could clearly drop, well into the second half of July.

No significant cooling is expected, but temperatures would gradually normalize. It will continue to be hot, but we will be able to breathe much better. All this without significant rain in sight. In any case, these three heatwaves will have occurred before we have officially reached the dog days of a summer that will be very long.